Emerson Rosemount 644 HART Reference Manual

Reference Manual

00809-0100-4728, Rev MB

Rosemount™ 644 Temperature Transmitter

®

with HART

For product shipped before September 2012

Protocol

July 2016

Reference Manual

00809-0100-4728, Rev MB

1Section 1: Introduction

2Section 2: Configuration

Contents

July 2016

1.1 Manual overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.2 Transmitter overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

1.3 Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

1.3.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

1.3.2 Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

1.3.3 Mechanical. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.3.4 Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.3.5 Environmental. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.4 Return of materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

1.5 Transmitter security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

1.5.1 Available security options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

2.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

2.2 Safety messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

2.3 System readiness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

2.3.1 Confirm correct device driver. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

2.3.2 Surges/transients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

2.4 Configuration methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

2.4.1 Configuring on the bench . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

2.4.2 Choosing a configuration tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

2.4.3 Setting the loop to manual. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

2.4.4 Failure mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

2.4.5 HART software Lock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

2.5 Verify configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

2.5.1 Using Field Communicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

2.5.2 Using AMS Device Manager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

2.5.3 Using Local Operator Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

2.5.4 Checking transmitter output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

2.6 Basic configuration of the transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

2.6.1 Mapping the HART variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

2.6.2 Configuring the sensor(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Content s

2.6.3 Setting output units. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

2.7 Configure dual sensor options. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

2.7.1 Differential temperature configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

2.7.2 Average temperature configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

2.7.3 Hot Backup configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

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2.7.4 Sensor Drift Alert configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

2.8 Configure device outputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

2.8.1 Rerange the transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

2.8.2 Damping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

2.8.3 Configure alarm and saturation levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

2.8.4 Configuring the LCD display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

2.9 Inputting device information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

2.9.1 Tag, Date, Descriptor and Message . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

2.10Configure measurement filtering. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

2.10.150/60 Hz filter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

2.10.2Resetting the device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

2.10.3Intermittent sensor detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

2.10.4Open Sensor Holdoff . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

2.11Diagnostics and service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

2.11.1Performing a loop test. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

2.11.2Simulate digital signal (Digital Loop Test). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

2.11.3Thermocouple Degradation Diagnostic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

2.11.4Min/Max Tracking diagnostic. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

2.12Establishing multidrop communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

2.12.1Changing a transmitter address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

2.13Using the transmitter with the HART Tri-Loop. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

2.13.1Set the transmitter to Burst Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

2.13.2Set process variable output order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

3Section 3: Hardware Installation

3.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

3.2 Safety messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

3.3 Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

3.3.1 Installation considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

3.3.2 Environmental considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

3.4 Installation procedures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

3.4.1 Set the alarm switch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

3.4.2 Mount the transmitter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

3.4.3 Install the device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

3.4.4 Multichannel installations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

3.4.5 LCD display Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

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4Section 4: Electrical Installation

5Section 5: Operation and Maintenance

Contents

July 2016

4.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

4.2 Safety messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

4.3 Wiring and powering the transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

4.3.1 Sensor connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

4.3.2 Power the transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

4.3.3 Ground the transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

4.3.4 Wiring with a Rosemount 333 HART Tri-Loop

5.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

5.2 Safety messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

5.3 Calibration overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

5.3.1 Trimming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

5.4 Sensor input trim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

5.4.1 Recall Factory Trim—Sensor trim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

™

(HART / 4–20 mA only) . . . . . . . . . . . . 60

5.4.2 Active calibrator and EMF compensation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

5.5 Trim the analog output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

5.5.1 Analog output trim or Scaled Analog Output Trim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

5.5.2 Analog output trim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

5.5.3 Scaled output trim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

5.6 Transmitter-Sensor Matching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

5.7 Switching HART Revision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

5.7.1 Using the Generic Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

5.7.2 Using Field Communicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

5.7.3 Using AMS Device Manager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

5.7.4 Using Local Operator Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

6Section 6: Troubleshooting

6.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

6.2 Safety messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

6.3 Troubleshooting the 4-20 mA/HART output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

6.4 Diagnostic messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

6.4.1 Diagnostic messages: Failed–Fix now. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

6.4.2 Diagnostic messages: Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

6.4.3 Other LCD display messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

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7Section 7: Safety Instrumented Systems (SIS) Certification

7.1 Safety Instrumented Systems (SIS) certification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

7.2 Rosemount 644 safety certified identification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

7.3 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

7.4 Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

7.5 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

7.5.1 Damping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

7.6 Alarm and saturation levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

7.7 Rosemount 644 SIS operation and maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

7.7.1 Proof test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

7.7.2 Abbreviated proof test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

7.7.3 Extended proof test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

7.8 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

7.8.1 Failure rate data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

7.8.2 Failure values. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

7.8.3 Product life . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

AAppendix A: Specifications and Reference Data

A.1 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

A.1.1 Functional . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

A.1.2 Physical. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

A.1.3 Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

A.1.4 Conformance to specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

A.2 4–20 mA / HART specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

A.2.1 Communication requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

A.2.2 Power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

A.2.3 Temperature limits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

A.2.4 Hardware and software failure mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

A.2.5 Custom alarm and saturation level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

A.2.6 Turn-on time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

A.2.7 Transient protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

A.2.8 Accuracy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

A.3 Dimensional drawings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

A.3.1 LCD display cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

A.3.2 Stainless steel housing for biotechnology, pharmaceutical industries, and

sanitary applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

A.4 Ordering information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

A.5 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

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BAppendix B: Product Certifications

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A.5.1 Transmitter configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

A.5.2 Standard HART Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

A.5.3 Tagging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

A.5.4 Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

A.6 Specifications and Reference Data for Rosemount 644 HART Head Mount. . . . . . . . . . . . . . . 97

A.6.1 Functional specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

A.6.2 Physical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

A.6.3 Performance specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

A.6.4 4–20 mA / HART Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

B.1 Approved manufacturing locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101

B.2 European Union Directive Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101

B.2.1 Ordinary Location Certification from FM Approvals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

B.2.2 Hazardous Locations Certifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

B.2.3 Other certifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

B.3 Rosemount 644 with Foundation Fieldbus and Profibus PA . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

B.3.1 European Union Directive Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

B.3.2 Hazardous Locations Certificates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

B.3.3 European Certifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104

B.3.4 IECEx Certifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

B.3.5 Japanese Certifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105

B.3.6 Combination Approvals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

B.3.7 Russian GOST Certifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

B.3.8 Kazakhstan GOST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

B.3.9 Ukraine GOST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

CAppendix C: Field Communicator Menu Trees and Fast Keys

C.1 Field Communicator menu trees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113

C.2 Field Communicator Fast Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119

DAppendix D: Local Operator Interface (LOI)

Content s

D.1 Number entry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

D.2 Text entry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

D.2.1 Scrolling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

D.3 Timeout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

D.4 Saving and canceling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

D.4.1 Saving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

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D.4.2 Canceling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124

D.5 LOI menu tree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125

D.6 LOI menu tree – extended menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126

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Rosemount™ 644 Temperature
Transmitter

Rosemount 644 Hardware Revision 30 1 1
Device Revision 7 8 9

®

HART

Read this manual before working with the product. For personal and system safety, and for optimum
product performance, make sure to thoroughly understand the contents before installing, using, or
maintaining this product.

The United States has two toll-free assistance numbers and one international number.

Customer Central
1-800-999-9307 (7:00 a.m. to 7:00 p.m. CST)

National Response Center
1-800-654-7768 (24 hours a day)

Equipment service needs
International
1-(952)-906-8888

Title Page

July 2016

Revision 5 5 7

1.1 Safety messages

Instructions and procedures in this section may require special precautions to ensure the safety of the
personnel performing the operations. Information that potentially raises safety issues is indicated by a

warning symbol ( ). Refer to the following safety messages before performing an operation preceded
by this symbol.

Failure to follow these installation guidelines could result in death or serious injury.

 Make sure only qualified personnel perform the installation.

Explosions could result in death or serious injury.

 Do not remove the connection head cover in explosive atmospheres when the circuit is live.
 Before connecting HART

installed in accordance with intrinsically safe or non-intrinsic field wiring practices.

 Verify that the operating atmosphere of the transmitter is consistent with the appropriate

hazardous locations certifications.

 All connection head covers must be fully engaged to meet explosion-proof requirements.
 Do not remove the thermowell while in operation.

Install and tighten thermowells and sensors before applying pressureInstallation of this transmitter
in an explosive environment must be in accordance with the appropriate local, national, and
international standards, codes, and practices. Review the approvals section of the Rosemount 644
Reference Manual for any restrictions associated with a safe installation.

 In an Explosion-Proof/Flameproof installation, do not remove the transmitter covers when power

is applied to the unit.Process leaks could result in death or serious injury.

Electrical shock could cause death or serious injury.

 Use extreme caution when making contact with the leads and terminals.

®

in an explosive atmosphere, make sure the instruments in the loop are

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The products described in this document are NOT designed for nuclear-qualified applications.

Using non-nuclear qualified products in applications that require nuclear-qualified hardware or
products may cause inaccurate readings.

For information on Rosemount nuclear-qualified products, contact an Emerson
Sales Representative.

™

Process Management

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Section 1 Introduction

1.1 Manual overview

This manual is designed to assist in the installation, operation, and maintenance of Rosemount™ 644
Head Mount and 644 Rail Mount Transmitters with the HART protocol.

Section 2: Configuration

This section provides instruction on the commissioning and operating of the Rosemount 644 HART
Transmitter. The information explains how to configure software functions and many configuration
parameters on an Asset Management System, a Field Communicator, and the Local Operator Interface
display option.

Section 3: Hardware installation

This section contains mechanical installation instructions for the transmitter.

Section 4: Electrical Installation

This section contains electrical installation instructions and considerations for the transmitter.

Introduction

July 2016

Section 5: Operation and maintenance

This section contains common operation and maintenance techniques for the transmitter.

Section 6: Troubleshooting

This section provides troubleshooting techniques for the most common transmitter operating
problems.

Section 7: Safety Instrumented Systems (SIS) Certification

This section provides identification, installation, configuration, operation and maintenance, and
inspection information for Safety Instrumented Systems as it pertains to the Rosemount 644 Head
Mount Temperature Transmitter.

Appendix A: Specifications and Reference Data

This section supplies transmitter specifications and reference data as well as transmitter ordering
information.

Appendix B: Product Certifications

This section contains the approved manufacturing locations, Hazardous Location Product Certification
information, European Union Directive information, and Installation Drawings.

Appendix C: Field Communicator Menu Trees and Fast Keys

This section contains Field Communicator menu trees and Field Communicator Fast Keys.

Appendix D: Local Operator Interface (LOI)

Introduction

This section contains instructions for number entry, text entry, as well as the LOI menu tree and LOI
extended menu tree.

1

Introduction

July 2016

1.2 Transmitter overview

The Rosemount 644 Head Mount Temperature Transmitter supports the following features:

 HART configuration with Selectable HART revision capability (Revisions 5 or 7)

 Accepts either 1 or 2 inputs from a wide variety of sensor types (2-, 3-, and 4-wire RTD, Thermocouple,

mV, and Ohm)

 A compact transmitter size with electronics completely encapsulated in protective silicone and

enclosed in a plastic housing, ensuring long-term transmitter reliability

 Optional Safety Certification Option (IEC 61508 SIL 2)

 Optional Enhanced accuracy and stability performance

 Optional LCD display with extended temperature ratings of -40 °C to 85 °C

 Optional advanced LCD display with local operator interface (LOI) with extended temperature ratings

of -40 °C to 80 °C

 Two housing materials (Aluminum and SST) and various housing style options that allow for mounting

flexibility in a variety of environmental conditions

 Special dual-sensor features include Hot Backup

average temperature measurements, and four simultaneous measurement variable outputs in
addition to the analog output signal

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™

, Sensor Drift Alert, first good, differential and

 Additional advanced features include: Thermocouple Degradation Diagnostic, which monitors

thermocouple health, and process and transmitter Minimum/Maximum Temperature Tracking

The Rosemount 644 Rail Mount Temperature Transmitter supports the following features:

 4-20 mA/HART protocol (Revision 5)

 Accepts 1 sensor input from a wide variety of sensor types (2-, 3-, and 4-wire RTD, Thermocouple, mV,

and Ohm)

 Completely encapsulated electronics to ensure long term transmitter reliability

Refer to the following literature for a full range of compatible connection heads, sensors, and
thermowells provided by Emerson

 Temperature Sensors and Assemblies Product Data Sheet, Volume 1 (document number

00813-0100-2654)

 Temperature Sensors and Assemblies Product Data Sheet, Volume 2 (document number

00813-0200-2654)

1.3 Considerations

1.3.1 General

Electrical temperature sensors such as RTDs and thermocouples produce low-level signals proportional
to their sensed temperature. The Rosemount 644 converts the low-level sensor signal to a standard 4–20
mA DC or digital HART signal that is relatively insensitive to lead length and electrical noise. This signal is
then transmitted to the control room via two wires.

™

Process Management.

1.3.2 Commissioning

The transmitter can be commissioned before or after installation. It may be useful to commission it on
the bench, before installation, to ensure proper operation and to become familiar with its functionality.

2

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Make sure the instruments in the loop are installed in accordance with intrinsically safe, or non-incendive
field wiring practices.

1.3.3 Mechanical

Location

When choosing an installation location and position, take into account the need for access to the
transmitter.

Special mounting

Special mounting hardware is available for mounting a Rosemount 644 Head Mount Transmitter to a DIN
rail or assembling a new Rosemount 644 Head Mount to an existing threaded sensor connection head
(former option code L1).

1.3.4 Electrical

Proper electrical installation is necessary to prevent errors due to sensor lead resistance and electrical
noise. For best results, shielded cable should be used in electrically noisy environments.

Make wiring connections through the cable entry in the side of the housing. Be sure to provide adequate
clearance for cover removal.

Introduction

July 2016

1.3.5 Environmental

The transmitter electronics module is permanently sealed within a plastic enclosure, resisting moisture
and corrosive damage. Verify that the operating atmosphere of the transmitter is consistent with the
appropriate hazardous locations certifications.

Temperature effects

The transmitter will operate within specifications for ambient temperatures between –40 and 185 °F
(–40 and 85 °C). Heat from the process is transferred from the thermowell to the transmitter housing. If
the expected process temperature is near or beyond specification limits, consider the use of additional
thermowell lagging, an extension nipple, or a remote mounting configuration to isolate the transmitter
from the process.

Figure 1-1 provides an example of the relationship between transmitter housing temperature rise and

extension length.

Introduction

3

Introduction

Housing Temperature Rise, Above Ambient

°C (°F)

3 4 5 6 7 8 9

0

60 (108)

50 (90)

40 (72)

30 (54)

20 (36)

10 (18)

3.6

22

Extension Length (in.)

815 °C (1500 °F) Oven Temperature

540 °C (1000 °F)
Oven Temperature

250 °C (482 °F) Oven Temperature

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Figure 1-1. Rosemount 644 Head Mount Transmitter Connection Head Temperature Rise vs.

Extension Length

Example

The maximum permissible housing temperature rise (T) can be calculated by subtracting the maximum
ambient temperature (A) from the transmitter’s ambient temperature specification limit (S). For
instance, if A = 40 °C.

For a process temperature of 540 °C (1004 °F), an extension length of 3.6 inches (91.4 mm) yields a
housing temperature rise (R) of 22 °C (72 °F), providing a safety margin of 23 °C (73 °F). A 6.0 inch (152.4
mm) extension length (R = 10 °C (50 °F)) offers a higher safety margin (35 °C (95 °F)) and reduces tem­perature-effect errors but would probably require extra transmitter support. Gauge the requirements for
individual applications along this scale. If a thermowell with lagging is used, the extension length may be
reduced by the length of the lagging.

1.4 Return of materials

To expedite the return process in North America, call the Emerson™ Process Management National
Response Center toll-free at 800-654-7768. This center, available 24 hours a day, will assist you with any
needed information or materials.

The center will ask for the following information:

 Product model

 Serial numbers

 The last process material to which the product was exposed

T = S - A

T = 85 °C – 40 °C

T = 45 °C

4

The center will provide

 A Return Material Authorization (RMA) number

 Instructions and procedures that are necessary to return goods that were exposed to hazardous

substances

For other locations, contact an Emerson Process Management sales representative.

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Note

If a hazardous substance is identified, a Material Safety Data Sheet (MSDS), required by law to be
available to people exposed to specific hazardous substances, must be included with the returned
materials.

1.5 Transmitter security

1.5.1 Available security options

There are three security methods to utilize with the Rosemount 644 Transmitter.

 Software Security Switch (Write Protect)

 HART Lock

 LOI Password

The Write Protect feature allows you to protect the transmitter data from accidental or unwarranted
configuration changes. To enable the write protect feature, perform the following procedures.

Configuring Write Protect, HART Lock and LOI Password with a Field
Communicator

Introduction

July 2016

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys-Write Protect

Device Dashboard Fast Keys-HART Lock

Device Dashboard Fast Keys- LOI Password

2, 2, 9, 1

2, 2, 9, 2

2, 2, 9, 3

Configuring Write Protect, HART Lock and LOI Password with AMS
Device Manager

Right click on the device and select the Configure menu.

1. In the left navigation pane choose Manual Setup then chose the Security tab.

2. All three parameters can be configured from this screen.

3. Click Apply when complete.

™

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5

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6

Introduction

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Section 2 Configuration

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 7

Safety messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 7

System readiness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 8

Configuration methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 9

Verify configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 13

Basic configuration of the transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 15

Configure dual sensor options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 19

Configure device outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 25

Inputting device information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 31

Configure measurement filtering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 32

Diagnostics and service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 35

Establishing multidrop communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .page 39

Using the transmitter with the HART Tri-Loop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 40

Configuration

July 2016

2.1 Overview

This section contains information on commissioning and tasks that should be performed on the bench
prior to installation. Field Communicator, AMS

instructions are given to perform configuration functions. For convenience, Field Communicator Fast Key
sequences are labeled “Fast Keys,” and abbreviated LOI menus are provided for each function below. The
LOI is only available on the Rosemount 644 Head Mount design and the configuration instructions
referencing the interface will not apply to the rail mount form factor.

Full Field Communicator menu trees and Fast Key sequences are available in Appendix C: Field

Communicator Menu Trees and Fast Keys. LOI menu trees are available in Appendix D: Local Operator
Interface (LOI).

2.2 Safety messages

Instructions and procedures in this section may require special precautions to ensure the safety of the
personnel performing the operations. Information that potentially raises safety issues is indicated by a

warning symbol ( ). Refer to the following safety messages before performing an operation preceded
by this symbol.

™

Device Manager, and Local Operator Interface (LOI)

Config uration

7

Configuration

July 2016

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Failure to follow these installation guidelines could result in death or serious injury.

 Make sure only qualified personnel perform the installation.

Explosions could result in death or serious injury.

 Do not remove the connection head cover in explosive atmospheres when the circuit is live.
 Before connecting a Field Communicator in an explosive atmosphere, make sure the instruments in

the loop are installed in accordance with intrinsically safe or non-incendive field wiring practices.

 Verify the operating atmosphere of the transmitter is consistent with the appropriate hazardous

locations certifications.

 All connection head covers must be fully engaged to meet explosion-proof requirements.

Process leaks could result in death or serious injury.

 Do not remove the thermowell while in operation.
 Install and tighten thermowells and sensors before applying pressure.

Electrical shock could cause death or serious injury.

 Use extreme caution when making contact with the leads and terminals.

2.3 System readiness

Confirm HART® revision capability

 If using HART based control or asset management systems, confirm the HART capability of those

systems prior to transmitter installation. Not all systems are capable of communicating with HART
Revision 7 protocol. This transmitter can be configured for either HART Revision 5 or 7.

 For instructions on how to change the HART revision of your transmitter, see “Switching HART

Revision” on page 82.

8

Configuration

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2.3.1 Confirm correct device driver

 Verify the latest Device Driver files are loaded on your systems to ensure proper communications.
 Download the latest Device Driver at www.EmersonProcess.com or www.HartComm.org

Table 2-1. Rosemount 644 Device Revisions and Files

Configuration

July 2016

Software

date

Identify device

NAMUR

Date

software

revision

June

2012

1. NAMUR Software Revision is located on the hardware tag of the device. HART Software Revision can be read using a HART communication
tool.

2. Device Driver file names use Device and DD Revision, e.g. 10_01. HART Protocol is designed to enable legacy device driver revisions to
continue to communicate with new HART devices. To access new functionality, the new Device Driver must be downloaded. It is
recommended to download the new Device Driver files to ensure full functionality.

3. HART Revision 5 and 7 Selectable. Dual Sensor support, Safety Cer tified, Advanced Diagnostics (if ordered), Enhanced Accuracy and
Stability (if ordered).

1.1.1 01

software

revision

2.3.2 Surges/transients

The transmitter will withstand electrical transients of the energy level encountered in static discharges or
induced switching transients. However, high-energy transients, such as those induced in wiring from
nearby lightning strikes, welding, heavy electrical equipment, or switching gears, can damage both the
transmitter and the sensor. To protect against high-energy transients, install the transmitter into a
suitable connection head with the Rosemount 470 Transient Protector. Refer to the Rosemount 470
Transient Protector Product Data Sheet (document number 00813-0100-4191) for more information.

HART

Find device driver

files

HART

universal

revision

5 8

7 9

(1)

Device

revision

(2)

Review

instructions

Manual

document

number

00809-0100-4728

Review functionality

Changes to
software

See footnote 3 for list of

changes

(3)

2.4 Configuration methods

Set all transmitter hardware adjustments during commissioning to avoid exposing the transmitter
electronics to the plant environment after installation.

The Rosemount 644 can be configured either before or after installation. Configuring the transmitter on
the bench using either a Field Communicator, AMS Device Manager, or Local Operator Interface (LOI)
ensures all transmitter components are in working order prior to installation.

The Rosemount 644 Transmitter can be configured either on-line or off-line using a Field Communicator,
AMS Device Manager or the optional Local Operator Interface (LOI) (Head mount only). During on-line
configuration, the transmitter is connected to a Field communicator. Data is entered in the working
register of the communicator and sent directly to the transmitter.

Off-line configuration consists of storing configuration data in a Field Communicator while it is not
connected to a transmitter. Data is stored in nonvolatile memory and can be downloaded to the
transmitter at a later time.

Config uration

9

Configuration

Field Communicator

Power
Supply

July 2016

2.4.1 Configuring on the bench

To configure on the bench, required equipment includes a power supply, a digital multimeter (DMM),
and a Field Communicator, AMS Device Manager, or a Local Operator Interface (LOI – Option M4).

Connect the equipment as shown in Figure 2-1. Connect HART Communication leads at any termination
point in the signal loop. To ensure successful HART communication, a resistance of at least 250 ohms
must be present between the transmitter and the power supply. Connect the Field Communicator leads
to the clips behind the power (+,-) terminals on the top of the device. Avoid exposing the transmitter
electronics to the plant environment after installation by setting all transmitter jumpers during the
commissioning stage on the bench.

Figure 2-1. Powering the Transmitter for Bench Configuration

Rosemount 644 Head Mount Rosemount 644 Rail Mount

Reference Manual

00809-0100-4728, Rev MB

Note: Signal loop may be grounded at any point or left ungrounded.
Note: A Field Communicator may be connected at any termination point in the signal loop. The signal loop must have between 250 and 1100

ohms load for communications.

Note: Max torque is 6 in.-lbs (0/7 N-m)

2.4.2 Choosing a configuration tool

Configuring with a Field Communicator

The Field Communicator is a handheld device that exchanges information with the transmitter from the
control room, the instrument site, or any wiring termination point in the loop. To facilitate
communication, connect the Field Communicator, shown in this manual, in parallel with the transmitter
(see Figure 2-1). Use the loop connection ports on the rear panel of the Field Communicator. The
connections are non-polarized. Do not make connections to the serial port or the NiCad recharger jack in
explosive atmospheres. Before connecting the Field Communicator in an explosive atmosphere make
sure the instruments in the loop are installed in accordance with intrinsically safe or non-incendive field
wiring practices.

There are two interfaces available with the Field Communicator: Traditional and Dashboard interfaces.
All steps using a Field Communicator will be using Dashboard interfaces. Figure 2-2 shows the Device
Dashboard interface. As stated in “System readiness” on page 8, it is critical that the latest DD’s are
loaded into the Field Communicator for optimal transmitter performance.

Visit www.emersonprocess.com to download latest DD library.

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Configuration

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Turn on the Field Communicator by pressing the ON/OFF key. The Field Communicator will search for a
HART-compatible device and indicate when the connection is made. If the Field Communicator fails to
connect, it indicates that no device was found. If this occurs, refer to Section 6: Troubleshooting.

Figure 2-2. Field Communicator Device Dashboard Interface

Field Communicator menu trees and Fast Keys are available in Appendix C: Field Communicator Menu

Trees and Fast Keys Configuring with AMS Device Manager

Configuration

July 2016

With an AMS Device Manager software package, you can commission and configure instruments,
monitor status and alerts, troubleshoot from the control room, perform advanced diagnostics, manage
calibration, and automatically document activities with a single application.

Full configuration capability with AMS Device Manager requires loading the most current Device
Descriptor (DD) for this device. Download the latest DD at www.emersonprocess.com, or www.hart­comm.org.

Note

All steps listed in this product manual using AMS Device Manager assume the use Version 11.5.

Configuring with a Local Operator Interface

The LOI requires option code M4 to be ordered. To activate the LOI push either configuration button.
Configuration buttons are located on the LCD display (must remove housing cover to access the
interface. See Ta bl e 2 - 2 for configuration button functionality and Figure 2-3 for configuration button
location. When using the LOI for configuration, several features require multiple screens for a successful
configuration. Data entered will be saved on a screen-by-screen basis; the LOI will indicate this by flashing
"SAVED" on the LCD display each time.

Note

Entering into the LOI menu effectively disables the ability to write to the device by any other host or
configuration tool. Make sure this is communicated to necessary personnel before using the LOI for
device configuration.

Config uration

11

Configuration

A

July 2016

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Figure 2-3. LOI Configuration Buttons

A. Configuration buttons

Table 2-2. LOI Button Operation

Button

Left No SCROLL
Right Yes ENTER

Local Operator Interface password

A Local Operator Interface Password can be entered and enabled to prevent review and
modification of device configuration via the LOI. This does not prevent configuration from HART
or through the control system. The LOI password is a 4 digit code that is to be set by the user. If
the password is lost or forgotten the master password is “9307”. The LOI password can be
configured and enabled/disabled by HART communication via a Field Communicator, AMS
Device Manager, or the LOI.

Local Operator Interface menu trees are available in Appendix D: Local Operator Interface (LOI).

2.4.3 Setting the loop to manual

When sending or requesting data that would disrupt the loop or change the output of the
transmitter, set the process application loop to manual. The Field Communicator, AMS Device
Manager or LOI will prompt you to set the loop to manual when necessary. Acknowledging this
prompt does not set the loop to manual. The prompt is only a reminder; set the loop to

manual as a separate operation.

2.4.4 Failure mode

12

As part of normal operation, each transmitter continuously monitors its own performance. This
automatic diagnostics routine is a timed series of checks repeated continuously. If diagnostics
detect an input sensor failure or a failure in the transmitter electronics, the transmitter drives its
output to low or high depending on the position of the failure mode switch. If the sensor
temperature is outside the range limits, the transmitter saturates its output to 3.9 mA for
standard configuration on the low end (3.8 mA if configured for NAMUR-compliant operation)
and 20.5 mA on the high end (or NAMUR-compliant). These values are also custom configurable

Configuration

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00809-0100-4728, Rev MB

by the factory or using the Field Communicator.The values to which the transmitter drives its output in
failure mode depend on whether it is configured to standard, NAMUR-compliant, or custom operation.
See “Hardware and Software Failure Mode” on page 108 for standard and NAMUR-compliant operation
parameters.

2.4.5 HART software Lock

The HART Software Lock prevents changes to the transmitter configuration from all sources; all changes
requested via HART by the Field Communicator, AMS Device Manager or the LOI will be rejected. The
HART Lock can only be set via HART communication, and is only available in HART Revision 7 mode. The
HART Lock can be enabled or disabled with a Field Communicator or AMS Device Manager.

Configuring HART lock using a Field Communicator

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

Configuring HART lock using AMS Device Manager

1. Right click on the device and select Configure.

Configuration

July 2016

3, 2, 1

2. Under Manual Setup select the Security tab.

3. Click Lock/Unlock button under HART Lock (Software) and follow the screen prompts.

2.5 Verify configuration

It is recommended that various configuration parameters are verified prior to installation into the
process. The various parameters are detailed out for each configuration tool. Depending on what
configuration tool(s) are available follow the steps listed relevant to each tool.

2.5.1 Using Field Communicator

Configuration parameters listed in Figure 2-4 below are the basic parameters that should be reviewed
prior to transmitter installation. A full list of configuration parameters that can be reviewed and
configured using a Field Communicator are located in Appendix C: Field Communicator Menu Trees and

Fast Keys. A Rosemount 644 Device Descriptor (DD) must be installed on the Field Communicator to

verify configuration.

1. Verify device configuration using Fast Key sequences in Figure 2-4.
a. From the HOME screen, enter the Fast Key sequences listed in Figure 2-4.

Config uration

13

Configuration

July 2016

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00809-0100-4728, Rev MB

Figure 2-4. Rosemount 644 Device Dashboard Fast Key Sequences

Fast Key Sequence

Function HART 5 HART 7

Alarm Values 2, 2, 5, 6 2, 2, 5, 6

Damping Values 2, 2, 1, 5 2, 2, 1, 6

Lower Range Value (LRV) 2, 2, 5, 5, 3 2, 2, 5, 5, 3

Upper Range Value (URV) 2, 2, 5, 5, 2 2, 2, 5, 5, 2

Primary Variable 2, 2, 5, 5, 1 2, 2, 5, 5, 1

Sensor 1 Configuration 2, 1, 1 2, 1, 1

Sensor 2 Configuration

Ta g 2, 2, 7, 1, 1 2, 2, 7, 1, 1

Units 2, 2, 1, 5 2, 2, 1, 4

1. Available only if option code (S) is ordered.

(1)

2, 1, 1 2, 1, 1

2.5.2 Using AMS Device Manager

Right click on the device and select Configuration Properties from the menu. Navigate the tabs to
review the transmitter configuration data.

2.5.3 Using Local Operator Interface

Press any configuration button to activate the LOI. Select VIEW CONFIG to review the below parameters.
Use the configuration buttons to navigate through the menu. The parameters to be reviewed prior to
installation include:

 Tag
 Sensor Configuration
 Units
 Alarm and Saturation Levels
 Primary Variable
 Range Values
 Damping

2.5.4 Checking transmitter output

Before performing other transmitter on-line operations, review the Rosemount 644 digital output
parameters to ensure the transmitter is operating properly and is configured to the appropriate process
variables.

14

Checking or setting process variables

The Process Variables menu displays process variables, including sensor temperature, percent of range,
analog output, and terminal temperature. These process variables are continuously updated. The default
primary variable is Sensor 1. The secondary variable is the transmitter terminal temperature by default.

Configuration

Reference Manual

ON/OFFVIEW CONFIG
ZERO TRIM
UNITS
RERANGE
LOOP TEST

DISPLAY

DISPLAY

EXTENDED MENU
EXIT MENU

SENSOR 1
SENSOR 2*
ANALOG
PV
AVG
1ST GOOD
DIFF
% RANGE
TERM
MNMAX1*
MNMAX2*
MNMAX3*
MNMAX4*
BACK TO MENU
EXIT MENU

00809-0100-4728, Rev MB

Using a Field Communicator

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

Using AMS Device Manager

Right click on the device and select Service Tools from the menu. The Variabl es tab displays the following
process variables:

 Primary, Second, Third and Fourth variables, as well as the Analog Output

Using Local Operator Interface

To check the process variables from the LOI, the user must first configure the display to show the desired
variables (see “Configuring the LCD display” on page 30). Once the desired device variables are chosen,
simply EXIT the LOI menu and view the alternating values on the display screen.

Configuration

July 2016

3, 2, 1

2.6 Basic configuration of the transmitter

2.6.1 Mapping the HART variables

Config uration

The Rosemount 644 must be configured for certain basic variables in order to be operational. In many
cases, all of these variables are pre-configured at the factory. Configuration may be required if the
transmitter is not configured or if the configuration variables need revision.

Using a Field Communicator

The Variable Mapping menu displays the sequence of the process variables. Select the sequence below to
change this configuration. The Rosemount 644 single sensor input configuration screens allow selection
of the primary variable (PV) and the secondary variable (SV). When the Select PV screen appears, Snsr 1
must be selected.

15

Configuration

CALIBRAT
DAMPING

VARIABLE MAP

VARIABLE MAP

TAG
ALM SAT VALUES
PASSWORD

....

RE-MAP PV
RE-MAP 2V
RE-MAP 3V
RE-MAP 4V

....

VIEW CONFIG
SENSOR CONFIG
UNITS
RERANGE
LOOP TEST
DISPLAY

EXTENDED MENU

EXTENDED MENU

EXIT MENU

July 2016

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The Rosemount 644 dual-sensor option configuration screens allow selection of the primary variable
(PV), secondary variable (SV), tertiary variable (TV), and quaternary variable (QV). Variable choices are:

 Sensor 1
 Sensor 2
 Differential Temperature
 Average Temperature
 Termina l Temp erature
 Not Used

The 4-20 mA analog signal represents the Primary Variable.

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

2, 2, 8, 6

Using AMS Device Manager

Right click on the device and select the Configure menu.

1. In the left navigation pane choose Manual Setup then on the HART tab.

2. Map each variable individually or use the Re-map Variables method to guide you through the
re-mapping process.

3. Click Apply when complete.

Using the Local Operator Interface

Follow flow chart to select the desired mapped variables. Use the SCROLL and ENTER buttons to select
each variable. Save by selecting SAVE as indicated on the LCD screen when prompted. See Figure 2-5 on

page 16 for an example of a mapped variable with the LOI.

Figure 2-5. Mapping Variables with LOI

2.6.2 Configuring the sensor(s)

16

Sensor configuration includes setting the information for:

 Sensor Type
 Connection Type
 Units
 Damping values
 Sensor Serial Number
 RTD 2-Wire Offset

Configuration

Reference Manual

VIEW SENSORVIEW SENSOR
SENSOR CONFIGSENSOR CONFIG

BACK TO MENU
EXIT MENU

VIEW S1 CONFIG
VIEW S2 CONFIG*
BACK TO MENU
EXIT MENU

VIEW CONFIG

SENSOR CONFIG

SENSOR CONFIG

UNITS
RERANGE
LOOP TEST
DISPLAY
EXTENDED MENU
EXIT MENU

SENSOR 1 CONFIG
SENSOR 2 CONFIG*
BACK TO MENU
EXIT MENU

00809-0100-4728, Rev MB

Using a Field Communicator

The Configure Sensors method will guide you through the configuration of all necessary settings
associated with configuring a sensor including:

For a full list of Sensor Types available with the Rosemount 644 and their associated levels of accuracy,
see Table A-2 on page 110.

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

Using AMS Device Manager

Right click on the device and select Configure.

1. In the left navigation pane choose Manual Setup and choose the Sensor 1 or Sensor 2 tab
depending on the need.

2. Individually select the Sensor Type, Connection, Units and other sensor related information as desired
from the drop down menus on the screen.

3. Click Apply when complete.

Configuration

July 2016

2, 1, 1

Using Local Operator Interface

Reference the below image for guidance on where to find Sensor Configuration in the LOI menu.

Figure 2-6. Configuring Sensors with LOI

* Available only if option code (S) is ordered.

Contact a Emerson Process Management representative for information on the temperature sensors,
thermowells, and accessory mounting hardware that is available through Emerson Process
Management.

2-wire RTD offset

The 2-wire Offset feature allows the measured lead wire resistance to be input and corrected for, which
results in the transmitter adjusting its temperature measurement for the error caused by this added
resistance. Because of a lack of lead wire compensation within the RTD, temperature measurements
made with a 2-wire RTD are often inaccurate.

Config uration

This feature can be configured as a subset of the Sensor Configuration process in the Field
Communicator, AMS Device Manager, and the Local Operator Interface.

To utilize this feature properly perform the following steps:

17

Configuration

July 2016

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00809-0100-4728, Rev MB

1. Measure the lead wire resistance of both RTD leads after installing the 2-Wire RTD and Rosemount

644.

2. Navigate to the 2-Wire RTD Offset parameter:

3. Enter the total measured resistance of the two RTD leads at the 2-Wire Offset prompt to ensure proper
adjustment. The transmitter will adjust its temperature measurement to correct the error caused by
lead wire resistance.

Enter 2-wire offset with Field Communicator

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

Enter 2-wire offset with AMS Device Manager

1. Right click on the device and select Configure.

2. In the left navigation pane choose Manual Setup and choose the Sensor 1 or Sensor 2 tab
depending on the need. Find the 2-Wire Offset text field and enter the value.

3. Click Apply when complete.

2.6.3 Setting output units

The Units can be configured for a number of different parameters in the Rosemount 644. Individual Units
can be configured for:

 Sensor 1
 Sensor 2
 Termina l Temp erature
 Differential Temperature
 Average Temperature
 First Good Temperature

Each of the base parameters and calculated outputs from those values can have a Unit of measure
associated with it. Set the transmitter output to one of the following engineering units:

 Degrees Celsius
 Degrees Fahrenheit
 Degrees Rankine
 Kelvin
 Ohms
 Millivolts

2, 1, 1

18

Configuration

Reference Manual

CHANGE ALLCHANGE ALL

SENSOR 1 UNITS
SENSOR 2 UNITS*
DIFF UNITS*
AVERAGE UNITS*
1ST GOOD UNITS**
BACK TO MENU
EXIT MENU

DEG C UNITS
DEG F UNITS
DEG R UNITS
KELVIN UNITS
MV UNITS
OHM UNITS
BACK TO MENU
EXIT MENU

VIEW CONFIG
SENSOR CONFIG

UNITS

UNITS

RERANGE
LOOP TEST
DISPLAY
EXTENDED MENU
EXIT MENU

00809-0100-4728, Rev MB

Using a Field Communicator

Configuration

July 2016

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

HART 5 HART 7

2, 2, 1, 4 2, 2, 1, 5

Using AMS Device Manager

1. Right click on the device and select Configure.

2. In the left navigation pane choose Manual Setup. The unit fields for various variables are
spread over the Manual Setup tabs, click through the tabs and change the desired units.

3. Click Apply when complete.

Using Local Operator Interface

Reference the below image for where to find the Units configuration in the LOI menu.

Figure 2-7. Configuring Units with LOI

2.7 Configure dual sensor options

2.7.1 Differential temperature configuration

Config uration

* Available only if option code (S) is ordered.

** Available only if option Codes (S) and (DC) are both ordered.

Note

The list of choices available for Units after the primary menu is dependent on sensor
configuration settings.

Dual-sensor configuration deals with the functions that can be used with a transmitter ordered
with Dual Sensor inputs. In the Rosemount 644 these functions include:

 Differential Temperature
 Average Temperature
 Hot Backup

™

and Sensor Drift Alert Diagnostics (requires option code DC)

– First Good Temperature (requires options S and DC)

The Rosemount 644 ordered and configured for dual-sensors can accept any two inputs then
display the differential temperature between them. Use the following procedures to configure
the transmitter to measure differential temperature.

19

Configuration

CHANGE ALL
SENSOR 1 UNITS
SENSOR 2 UNITS*

DIFFRNTL UNITS*

DIFFRNTL UNITS*

AVERAGE UNITS*
1

ST

GOOD UNITS**

BACK TO MENU
EXIT MENU

DEG C UNITS
DEG F UNITS
DEG R UNITS
KELVIN UNITS
MV UNITS
OHM UNITS
BACK TO MENU
EXIT MENU

VIEW CONFIG
SENSOR CONFIG

UNITS

UNITS

RERANGE
LOOP TEST
DISPLAY
EXTENDED MENU
EXIT MENU

CALIBRAT

DAMPING

DAMPING

VARIABLE MAP
TAG
ALARM SAT VALUES
PASSWORD

....

PV DAMP
SENSOR 1 DAMP
SENSOR 2 DAMP*

DIFFRNTL

DIFFRNTL DAMP*DAMP*

AVERAGE DAMP*
1ST GOOD DAMP**
BACK TO MENU
EXIT MENU

VIEW CONFIG
SENSOR CONFIG
UNITS
RERANGE
LOOP TEST
DISPLAY

EXTENDED MENU

EXTENDED MENU

EXIT MENU

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Note

This procedure assumes the Differential Temperature is a calculated output of the device but does not
re-assign it as the Primary Variable. If it desired for Differential to be the transmitter’s primary variable
see “Mapping the HART variables” on page 15 to set it to PV.

Using Field Communicator

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

2, 2, 3, 1

Using AMS Device Manager

Right click on the device and select Configure.

1. In the left navigation pane choose Manual Setup.

2. On the Calculated Output Tab find the Differential Temperature group box.

3. Choose Units and Damping settings then click Apply when complete.

Using Local Operator Interface

To configure the Differential Temperature on the Local Operator Interface you will have to set the Units
and Damping values separately. Reference Figure 2-8 and Figure 2-9 below for where to find these in the
menu.

Figure 2-8. Configuring Differential Units with LOI

20

* Available only if option code (S) is ordered.

** Available only if option codes (S) and (DC) are both ordered.

Figure 2-9. Configuring Differential Damping with LOI

* Available only if option code (S) is ordered.

** Available only if option codes (S) and (DC) are both ordered.

Configuration

Reference Manual

CHANGE ALL
SENSOR 1 UNITS
SENSOR 2 UNITS*
DIFFRNTL UNITS*

AVERAGE UNITS

AVERAGE UNITS*

1ST GOOD UNITS**
BACK TO MENU
EXIT MENU

DEG C UNITS
DEG F UNITS
DEG R UNITS
KELVIN UNITS
MV UNITS
OHM UNITS
BACK TO MENU
EXIT MENU

VIEW CONFIG
SENSOR CONFIG

UNITS

UNITS

RERANGE
LOOP TEST
DISPLAY
EXTENDED MENU
EXIT MENU

00809-0100-4728, Rev MB

2.7.2 Average temperature configuration

The Rosemount 644 Transmitter ordered and configured for dual-sensors can output and display the
Average temperature of any two inputs. Use the following procedures to configure the transmitter to
measure the average temperature:

Note

This procedure assumes the Average Temperature is a calculated output of the device but does not
re-assign it as the Primary Variable. If it desired for Differential to be the transmitter’s primary variable
see “Mapping the HART variables” on page 15 to set it to PV.

Using a Field Communicator

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

Using AMS Device Manager

Right click on the device and select Configure.

Configuration

July 2016

2, 2, 3, 3

1. In the left navigation pane choose Manual Setup.

2. On the Calculated Output Tab find the Average Temperature group box.

3. Choose Units and Damping settings then click Apply when complete.

Using Local Operator Interface

To configure Average Temperature on the Local Operator Interface you will have to set the Units and
Damping values separately. Reference Figure 2-10 and Figure 2-11 below for where to find these in the
menu.

Figure 2-10. Configuring Average Units with LOI

* Available only if option code (S) is ordered.

** Available only if option codes (S) and (DC) are both ordered.

Config uration

21

Configuration

CALIBRAT

DAMPING

DAMPING

VARIABLE MAP
TAG
ALARM SAT VALUES
PASSWORD

....

PV DAMP
SENSOR 1 DAMP
SENSOR 2 DAMP*
DIFFRNTL DAMP*

AVERAGE DAMP

AVERAGE DAMP*

1ST GOOD DAMP**
BACK TO MENU
EXIT MENU

VIEW CONFIG
SENSOR CONFIG

UNITS

UNITS

RERANGE
LOOP TEST
DISPLAY
EXTENDED MENU
EXIT MENU

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Figure 2-11. Configuring Average Damping with LOI

* Available only if option code (S) is ordered.

** Available only if option codes (S) and (DC) are both ordered

Note

If Sensor 1 and/or Sensor 2 should fail while PV is configured for average temperature and Hot Backup is
not enabled, the transmitter will go into alarm. For this reason, it is recommended when PV is Sensor
Average, that Hot Backup be enabled when dual-element sensors are used, or when two temperature
measurements are taken from the same point in the process. If a sensor failure occurs when Hot Backup
is enabled, while PV is Sensor Average, three scenarios could result:

 If Sensor 1 fails, the average will only be reading from Sensor 2, the working sensor
 If Sensor 2 fails, the average will only be reading from Sensor 1, the working sensor
 If both sensors fail simultaneously, the transmitter will go into alarm and the status available (via

HART) states that both Sensor 1 and Sensor 2 have failed

In the first two scenarios, the 4-20 mA signal is not disrupted and the status available to the control
system (via HART) specifies which sensor has failed.

2.7.3 Hot Backup configuration

The Hot Backup feature configures the transmitter to automatically use Sensor 2 as the primary sensor if
Sensor 1 fails. With Hot Backup enabled, the primary variable (PV) must either be First Good or Average.
See the “NOTE” directly above for details on using Hot Backup when the PV is set to Average.

Sensors 1 or 2 can be mapped as the secondary variable (SV), tertiary variable (TV), or quaternary
variable (QV). In the event of a primary variable (Sensor 1) failure, the transmitter enters Hot Backup
mode and Sensor 2 becomes the PV. The 4–20 mA signal is not disrupted, and a status is available to the
control system through HART that Sensor 1 has failed. An LCD display, if attached, displays the failed
sensor status.

While configured to Hot Backup, if Sensor 2 fails but Sensor 1 is still operating properly, the transmitter
continues to report the PV 4–20 mA analog output signal, while a status is available to the control
system through HART that Sensor 2 has failed.

Resetting Hot Backup

22

In Hot Backup mode, if Sensor 1 does fail and Hot Backup is initiated, the transmitter will not revert back
to Sensor 1 to control the 4–20 mA analog output until the Hot Backup mode is reset by re-enabling
through HART, re-setting it through the LOI or by briefly powering down the transmitter.

Configuration

Reference Manual

CALIBRAT
DAMPING
VARIABLE MAP
TAG
ALM SAT VALUES
PASSWORD
SIMULATE
HART REV

HOT BACK CONFIG**

HOT BACK CONFIG**

DRIFT ALERT**

....

HOT BACK MODE
HOT BACK PV
HOT BACK RESET
BACK TO MENU
EXIT MENU

VIEW CONFIG
SENSOR CONFIG
UNITS
RERANGE
LOOP TEST
DISPLAY

EXTENDED MENU

EXTENDED MENU

EXIT MENU

00809-0100-4728, Rev MB

Hot Backup configuration with a Field Communicator

The field communicator will walk you through a method to correctly configure the necessary elements
of the Hot Backup feature.

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

Hot Backup configuration with AMS Device Manager

Right click on the device and select Configure.

1. In the left navigation pane choose Manual Setup.

2. On the Diagnostics Tab find the Hot Backup group box.

3. Choose the button “Configure Hot Backup” or “Reset Hot Backup” depending on the desired function
and walk through the guided steps.

4. Click Apply when complete.

Hot Backup configuration with Local Operator Interface

Configuration

July 2016

2, 1, 5

To configure Hot Backup on the Local Operator Interface, you will have to Enable the Mode and set the
PV values. Reference Figure 2-12 below for where to find these in the menu.

Figure 2-12. Configuring Hot Backup with LOI

* Available only if option code (S) is ordered.

** Available only if option Codes (S) and (DC) are both ordered.

For information on using Hot Backup in conjunction with the HART Tri-Loop™ see “Using the transmitter

with the HART Tri-Loop” on page 40.

2.7.4 Sensor Drift Alert configuration

Config uration

The Sensor Drift Alert command allows the transmitter to set a warning flag (through HART), or go into
analog alarm when the temperature difference between Sensor 1 and Sensor 2 exceeds a user-defined
limit.

This feature is useful when measuring the same process temperature with two sensors, ideally when
using a dual-element sensor. When Sensor Drift Alert mode is enabled, the user sets the maximum
allowable difference, in engineering units, between Sensor 1 and Sensor 2. If this maximum difference is
exceeded, a Sensor Drift Alert warning flag will be set.

23

Configuration

CALIBRAT
DAMPING
VARIABLE MAP
TAG
ALM SAT VALUES
PASSWORD
SIMULATE
HART REV
HOT BACK CONFIG**

DRIFT ALERT**

DRIFT ALERT**

....

DRIFT MODE
DRIFT LIMIT
DRIFT UNITS
DRIFT DAMP
BACK TO MENU
EXIT MENU

VIEW CONFIG
SENSOR CONFIG
UNITS
RERANGE
LOOP TEST
DISPLAY

EXTENDED MENU

EXTENDED MENU

EXIT MENU

July 2016

Reference Manual

00809-0100-4728, Rev MB

Though it defaults to WARNING, when configuring the transmitter for Sensor Drift Alert, the user also
has the option of specifying that the analog output of the transmitter go into ALARM when sensor
drifting is detected.

Note

Using dual sensor configuration in the Rosemount 644, the temperature transmitter supports the
configuration and simultaneous use of Hot Backup and Sensor Drift Alert. If one sensor fails, the
transmitter switches output to use the remaining good sensor. Should the difference between the two
sensor readings exceed the configured threshold, the AO will go to alarm indicating the sensor drift
condition. The combination of Sensor Drift Alert and Hot Backup improves sensor diagnostic coverage
while maintaining a high level of availability. Refer to the Rosemount 644 FMEDA report for the impact
on safety.

Using a Field Communicator

The field communicator will walk you through a method to correctly configure the necessary elements
of a Sensor Drift Alert feature.

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

2, 1, 6

Using AMS Device Manager

1. Right click on the device and select Configure.

2. On the Diagnostics Tab find the Sensor Drift Alert group box.

3. Choose to Enable the Mode and fill in the Units, Threshold and Damping values from the drop
downs provided or click the “Configure Sensor Drift Alert” button and walk through the guided
steps.

4. Click Apply when complete.

Using Local Operator Interface

To configure Sensor Drift Alert on the Local Operator Interface you will have to Enable the Mode, set the
PV, set the Drift Limit and set a value for Drift Alert Damping all separately. Reference Figure 2-13 below
for where to find these in the menu.

Figure 2-13. Configuring sensor drift alert with LOI

24

* Available only if option code (S) is ordered.

** Available only if option Codes (S) and (DC) are both ordered.

Configuration

Reference Manual

00809-0100-4728, Rev MB

Note

Enabling the Drift Alert Option to WARNING will set a flag (through the HART communications)
whenever the maximum acceptable difference between Sensor 1 and Sensor 2 has been exceeded. For
the transmitter’s analog signal to go into ALARM when Drift Alert is detected, select Alarm during the
configuration process.

2.8 Configure device outputs

2.8.1 Rerange the transmitter

Reranging the transmitter sets the measurement range to the limits of the expected readings for a
certain application. Setting the measurement range to the limits of expected readings maximizes
transmitter performance; the transmitter is most accurate when operated within the expected
temperature range for the application.

The range of expected readings is defined by the Lower Range Value (LRV) and Upper Range Value (URV).
The transmitter range values can be reset as often as necessary to reflect changing process conditions.
For a complete listing of Range & Sensor limits, refer to Table A-2 on page 110.

Configuration

July 2016

Note

The rerange functions should not be confused with the trim functions. Although the rerange function
matches a sensor input to a 4–20 mA output, as in conventional calibration, it does not affect the
transmitter’s interpretation of the input.

Select from one of the methods below to rerange the transmitter.

Using a Field Communicator

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

Lower Range Value Upper Range Value

2, 2, 5, 5, 3 2, 2, 5, 5, 2

Using AMS Device Manager

Right click on the device and select Configure.

1. In the left navigation pane choose Manual Setup.

2. On the Analog Output Tab find the Primary Variable Configuration group box.

3. Change the Upper Range Value and Lower Range Value to their desired settings.

4. Click Apply when complete.

Using Local Operator Interface

Reference the image below to find the Range Value configuration path on the LOI.

Config uration

25

Configuration

ENTER VALUESENTER VALUES

BACK TO MENU
EXIT MENU

LRVLRV
URVURV

BACK TO MENU
EXIT MENU

VIEW CONFIG
SENSOR CONFIG
UNITS

RERANGE

RERANGE

LOOP TEST
DISPLAY
EXTENDED MENU
EXIT MENU

Damped Value NP–

2TU–
2TU

------------------







P=

P =previous damped value

N =new sensor value

T = damping time constant

U =update rate

July 2016

Figure 2-14. Reranging the transmitter with LOI

2.8.2 Damping

The damping function changes the response time of the transmitter to smooth variations in output
readings caused by rapid changes in input. Determine the appropriate damping setting based on the
necessary response time, signal stability, and other requirements of the loop dynamics of the system.
The default damping value is 5.0 seconds and can be reset to any value between 1 and 32 seconds.

The value chosen for damping affects the response time of the transmitter. When set to zero (disabled),
the damping function is off and the transmitter output reacts to changes in input as quickly as the
intermittent sensor algorithm allows. Increasing the damping value increases transmitter response time.

Reference Manual

00809-0100-4728, Rev MB

With damping enabled, if the temperature change is within 0.2% of the sensor limits, the transmitter
measures the change in input every 500 milliseconds (for a single sensor device) and outputs values
according to the following relationship:

At the value to which the damping time constant is set, the transmitter output is at 63% of the input
change and it continues to approach the input according to the damping equation above.

For example, as illustrated in Figure 2-15, if the temperature undergoes a step change—within 0.2% of
the sensor limits—from 100 degrees to 110 degrees, and the damping is set to 5.0 seconds, the
transmitter calculates and reports a new reading every 500 milliseconds using the damping equation. At

5.0 seconds, the transmitter outputs 106.3 degrees, or 63% of the input change, and the output

continues to approach the input curve according to the equation above.

For information regarding the damping function when the input change is greater than 0.2% of the
sensor limits, refer to “Intermittent sensor detection” on page 33.

26

Configuration

Reference Manual

00809-0100-4728, Rev MB

Figure 2-15. Change in Input vs. Change in Output with Damping Set to 5 Seconds

Damping can be applied to a number of parameters in the Rosemount 644 Transmitter. Variables that
can be damped are:

 Primary Variable (PV)
 Sensor 1
 Sensor 2
 Differential Temperature
 Average Temperature
 1st Good Temperature

Configuration

July 2016

Note

The instructions below only refer to the damping of the Primary Variable (PV).

Using a Field Communicator

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

HART 5 HART 7

2, 2, 1, 5 2, 2, 1, 6

Using AMS Device Manager

Right click on the device and select Configure.

1. In the left navigation pane choose Manual Setup.

2. On the Sensor 1 Tab find the Setup group box.

3. Change the Damping Value to the desired setting.

4. Click Apply when complete.

Config uration

27

Configuration

CALIBRAT

DAMPING

DAMPING

VARIABLE MAP
TAG
ALM SAT VALUES
PASSWORD

....

PV DAMP
SENSOR 1 DAMP
SENSOR 2 DAMP*
DIFFRNTL DAMP*
AVERAGE DAMP*
1ST GOOD DAMP**
BACK TO MENU
EXIT MENU

VIEW CONFIG
SENSOR CONFIG
UNITS
RERANGE
LOOP TEST
DISPLAY

EXTENDED MENU

EXTENDED MENU

EXIT MENU

July 2016

Using Local Operator Interface

Reference the figure below to find the Damping configuration path on the LOI.

2.8.3 Configure alarm and saturation levels

In normal operation, the transmitter will drive the output in response to measurements between the
lower to upper saturation points. If the temperature goes outside the sensor limits, or if the output
would be beyond the saturation points, the output will be limited to the associated saturation point.

The Rosemount 644 Transmitter automatically and continuously performs self-diagnostic routines. If the
self-diagnostic routines detect a failure, the transmitter drives the output to configured alarm value
based on the position of the alarm switch. The alarm and saturation settings allow the alarm settings (Hi
or Low) and saturation values to be viewed and changed.

Reference Manual

00809-0100-4728, Rev MB

Failure mode alarm and saturation levels can be configured using a Field Communicator, AMS Device
Manager, and the LOI. The following limitations exist for custom levels:

 The low alarm value must be less than the Low Saturation level.
 The high alarm value must be higher than the High Saturation level.
 Alarm and saturation levels must be separated by at least 0.1 mA

The configuration tool will provide an error message if the configuration rule is violated.

See Ta bl e 2 - 3, Ta b l e 2- 4 , and Ta bl e 2 - 5 below for the common Alarm and Saturation levels.

Table 2-3. Rosemount Alarm and Saturation Values

Level 4–20 mA saturation 4–20 mA alarm

Low 3.9 mA  3.75 mA

High 20.5 mA  21.75 mA

Table 2-4. NAMUR-Compliant Alarm and Saturation Values

Level 4–20 mA saturation 4–20 mA alarm

Low 3.8 mA  3.6 mA

High 20.5 mA 22.5 mA

28

Configuration

Reference Manual

CALIBRAT
DAMPING
VARIABLE MAP
TAG

ALM SAT VALUES

ALM SAT VALUES

PASSWORD
SIMULATE
HART REV
HOT BACK CONFIG**
DRIFT ALERT**

....

ROSEMNT VALUES
NAMUR VALUES
OTHER VALUES
BACK TO MENU
EXIT MENU

VIEW CONFIG
SENSOR CONFIG
UNITS
RERANGE
LOOP TEST
DISPLAY

EXTENDED MENU

EXTENDED MENU

EXIT MENU

00809-0100-4728, Rev MB

Table 2-5. Custom Alarm and Saturation Values

Level 4–20 mA saturation 4–20 mA alarm

Low 3.7 mA - 3.9 mA 3.6 mA - 3.8 mA

High 20.1 mA - 22.9 mA 20.2 mA - 23.0 mA

Note

Transmitters set to HART multidrop mode send all saturation and alarm information digitally; saturation
and alarm conditions will not affect the analog output.

Using with a Field Communicator

From the HOME screen, enter the Fast Key sequence

Configuration

July 2016

Device Dashboard Fast Keys

2, 2, 5, 6

Using with AMS Device Manager

Right click on the device and select Configure.

1. In the left navigation pane choose Manual Setup.

2. On the Analog Output Tab find the Alarm and Saturation Levels group box.

3. Enter the High Alarm, High Saturation, Low Saturation and Low Alarm levels to the desired vales.

4. Click Apply when complete.

Usingh the Local Operator Interface

Reference the figure below to find the Alarm and Saturation value configuration path on the LOI.

Figure 2-16. Configuring Alarm and Saturation Values with LOI

Config uration

* Available only if option code (S) is ordered.

** Available only if option Codes (S) and (DC) are both ordered.

29

Configuration

July 2016

2.8.4 Configuring the LCD display

The LCD display configuration command allows customization of the LCD display to suit application
requirements. The LCD display will alternate between the selected items with each item displaying for a
3- second interval.

Reference Manual

00809-0100-4728, Rev MB

 Sensor 1

 Sensor 2

 Analog Output

 Primary Variable

 Average Temperature

 First Good Temperature

 Differential Temperature

 Percent of Range

 Term inal Temperat ure

 Min and Max 1

 Min and Max 2

 Min and Max 3

 Min and Max 4

Reference Figure 2-17 to view the differences between the LCD display and Local Operator Interface
display options available with the Rosemount 644.

Figure 2-17. LCD Display and Local Operator Interface Display

LCD display LOI display

30

Using a Field Communicator

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

2, 1, 4

Using AMS Device Manager

1. Right click on the device and select Configure.

2. In the left navigation pane choose Manual Setup.

3. On the Display Tab there will be a group box with all available variables that can be displayed.

4. Check and un-check the desired display variables, with a checked box indicating that the variable will
be displayed.

5. Click Apply when complete.

Configuration

Reference Manual

SENSOR 1
SENSOR 2*
ANALOG
PV
AVG*
1

ST

GOOD*
DIFF*
% RANGE
TERM
MNMAX1*
MNMAX2*
MNMAX3*
MNMAX4*
BACK TO MENU
EXIT MENU

VIEW CONFIG
SENSOR CONFIG
UNITS
RERANGE
LOOP TEST

DISPLAY

DISPLAY

EXTENDED MENU
EXIT MENU

00809-0100-4728, Rev MB

Using Local Operator Interface

Reference the figure below to find the Alarm and Saturation value configuration path on the LOI.

Figure 2-18. Configuring Alarm and Saturation Values with LOI

* Available only if option code (S) is ordered.

Configuration

July 2016

2.9 Inputting device information

2.9.1 Tag, Date, Descriptor and Message

Config uration

Access the transmitter information variables online using the Field Communicator or other suitable
communications device. The following is a list of transmitter information variables, including device
identifiers, factory-set configuration variables, and other information.

The Ta g, Date, Descriptor and Message are parameters that provide transmitter identification in large
installations. See below for a description and a process to enter these pieces of configurable device
information.

The Ta g variable is the easiest way to identify and distinguish between different transmitters in
multi-transmitter environments. It is used to label transmitters electronically according to the
requirements of the application. The defined Tag is automatically displayed when a HART-based
communicator establishes contact with the transmitter at power-up. The Tag is up to 8 characters and
the Long Tag (a parameter introduced with the HART 6 and 7 protocol) was extended to 32 characters
long. Neither parameter has any impact on the primary variable readings of the transmitter, it is only for
information.

The Date is a user-defined variable that provides a place to save the date of the last revision of
configuration information. It has no impact on the operation of the transmitter or the HART-based
communicator.

The Descriptor variable provides a longer user-defined electronic label to assist with more specific
transmitter identification than is available with tag. The descriptor may be up to 16 characters long and
has no impact on the operation of the transmitter or the HART-based communicator.

The Message variable provides the most specific user-defined means for identifying individual
transmitters in multi-transmitter environments. It allows for 32 characters of information and is stored
with the other configuration data. The message variable has no impact on the operation of the
transmitter or the HART-based communicator.

31

Configuration

CALIBRAT
DAMPING
VARIABLE MAP

TAG

TAG

ALM SAT VALUES
PASSWORD

....

VIEW CONFIG
SENSOR CONFIG
UNITS
RERANGE
LOOP TEST
DISPLAY

EXTENDED MENU

EXTENDED MENU

EXIT MENU

July 2016

Reference Manual

00809-0100-4728, Rev MB

Using a Field Communicator

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

1, 8

Using AMS Device Manager

1. Right click on the device and select Configure.

2. In the left navigation pane choose Manual Setup.

3. On the Device Tab there will be a group box called Identification, in the box find the fields Ta g, Date,
Descriptor and Message, and enter the desired characters.

4. Click Apply when complete.

Using Local Operator Interface

Reference the figure below to find the Tag configuration path in the LOI.

Figure 2-19. Configuring the Tag with LOI

2.10 Configure measurement filtering

2.10.1 50/60 Hz filter

32

The 50/60 Hz Filter (also known as Line Voltage Filter or AC Power Filter) function sets the transmitter
electronic filter to reject the frequency of the AC power supply in the plant. The 60 Hz or 50 Hz mode can
be chosen. The factory default for this setting is 60 Hz.

Note

In high noise environments, normal mode is recommended.

Configuring 50/60 Hz filter with a Field Communicator

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

2, 2, 7, 4, 1

Configuration

Reference Manual

00809-0100-4728, Rev MB

Configuring 50/60 Hz filter with AMS Device Manager

Right click on the device and select Configure.

1. In the left navigation pane choose Manual Setup.

2. On the Device Tab there will be a group box called Noise Rejection, in the box AC Power Filter
choose from the drop down menu.

3. Click Apply when complete.

2.10.2 Resetting the device

Processor Reset function resets the electronics without actually powering down the unit. It does not
return the transmitter to the original factory configuration.

Using a Field Communicator

From the HOME screen, enter the Fast Key sequence

Configuration

July 2016

Device Dashboard Fast Keys

Using AMS Device Manager

Right click on the device and select Service Tools.

1. In the left navigation pane choose Maintenance.

2. On the Reset/Restore Tab click the Processor Reset button.

3. Click Apply when complete.

2.10.3 Intermittent sensor detection

The Intermittent Sensor Detection feature (also known as the Transient Filter) is designed to guard
against erratic process temperature readings caused by intermittent open sensor conditions. An
intermittent sensor condition is an open sensor condition that lasts less than one update. By default, the
transmitter is shipped with the Intermittent Sensor Detection feature switched ON and the threshold
value set at 0.2% of sensor limits. The Intermittent Sensor Detect feature can be switched ON or OFF and
the threshold value can be changed to any value between 0 and 100% of the sensor limits with a Field
Communicator.

When the Intermittent Sensor Detection feature is switched ON, the transmitter can eliminate the
output pulse caused by intermittent open sensor conditions. Process temperature changes (T) within the
threshold value will be tracked normally by the transmitter’s output. A (T) greater than the threshold
value will activate the intermittent sensor algorithm. True open sensor conditions will cause the
transmitter to go into alarm.

3, 4, 6, 1

Config uration

The threshold value of the Rosemount 644 should be set at a level that allows the normal range of
process temperature fluctuations; too high and the algorithm will not be able to filter out intermittent
conditions; too low and the algorithm will be activated unnecessarily. The default threshold value is 0.2%
of the sensor limits.

When the Intermittent Sensor Detection feature is switched OFF, the transmitter tracks all process
temperature changes, even from an intermittent sensor. (The transmitter in effect behaves as though
the threshold value had been set at 100%.) The output delay due to the intermittent sensor algorithm
will be eliminated.

33

Configuration

July 2016

Reference Manual

00809-0100-4728, Rev MB

Using a Field Communicator

The following steps indicate how to turn the Intermittent Sensor Detect or Transient Filter) feature ON or
OFF. When the transmitter is connected to a Field Communicator, use the Fast Key sequence and choose

ON (normal setting) or OFF.

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

The threshold value can be changed from the default value of 0.2%. Turning the Intermittent Sensor
Detect feature OFF or leaving it ON and increasing the threshold value above the default does not affect
the time needed for the transmitter to output the correct alarm signal after detecting a true open sensor
condition. However, the transmitter may briefly output a false temperature reading for up to one update
in either direction up to the threshold value (100% of sensor limits if Intermittent Sensor Detect is OFF).
Unless a rapid response rate is necessary, the suggested setting is ON with 0.2% threshold.

2, 2, 7, 4, 2

Using AMS Device Manager

1. Right click on the device and select Configure.

2. In the left navigation pane choose Manual Setup.

3. On the Device Tab there will be a group box called Noise Rejection, in the box Transient Filter
Threshold, enter the desired percent.

4. Click Apply when complete.

2.10.4 Open Sensor Holdoff

The Open Sensor Holdoff option, at the normal setting, enables the Rosemount 644 to be more robust
under heavy EMI conditions. This is accomplished by the software having the transmitter perform
additional verification of the open sensor status prior to activating the transmitter alarm. If the
additional verification shows that the open sensor condition is not valid, the transmitter will not go into
alarm.

For users of the Rosemount 644 that desire a more vigorous open sensor detection, the Open Sensor
Holdoff option can be changed to a fast setting where the transmitter will report an open sensor
condition without additional verification of whether or not the open condition is valid.

Using a Field Communicator

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

Using AMS Device Manager

1. Right click on the device and select Configure.

2, 2, 7, 3

34

2. In the left navigation pane choose Manual Setup.

3. On the Device Tab there will be a group box called Open Sensor Hold Off. Change the Mode to either
Normal or Fast.

4. Click Apply when complete.

Configuration

Reference Manual

SET 4 MA
SET 20 MA
SET CUSTOM
END LOOP TEST
BACK TO MENU
EXIT MENU

VIEW CONFIG
SENSOR CONFIG
UNITS
RERANGE

LOOP TEST

LOOP TEST

DISPLAY
EXTENDED MENU
EXIT MENU

00809-0100-4728, Rev MB

2.11 Diagnostics and service

2.11.1 Performing a loop test

The Analog Loop Test verifies the output of the transmitter, the integrity of the loop, and the operations
of any recorders or similar devices installed in the loop. To initiate a loop test, follow the steps below.

The host system may provide a current measurement for the 4-20 mA HART output. If not, connect a
reference meter to the transmitter by either connecting the meter to the test terminals on the terminal
block, or shunting transmitter power through the meter at some point in the loop.

Using a Field Communicator

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

Using AMS Device Manager

1. Right click on the device and select Service Tools.

2. In the left navigation pane choose Simulate.

Configuration

July 2016

3, 5, 1

3. On the Simulate Tab find the Perform Loop Test button in the Analog Output Verification group
box.

4. Follow the guided instructions and click Apply when complete.

Using Local Operator Interface

Reference the figure below to find the path to the Loop Test in the LOI menu.

Figure 2-20. Configuring the Tag with LOI

2.11.2 Simulate digital signal (Digital Loop Test)

The Simulate Digital Signal function adds to the analog loop test by confirming the HART output values
are outputting correctly. Digital Loop Test is only available in HART Revision 7 mode.

Using a Field Communicator

Config uration

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

3, 5, 2

35

Configuration

CALIBRAT
DAMPING
VARIABLE MAP
TAG
ALM SAT VALUES
PASSWORD

SIMULATE

SIMULATE

HART REV

....

SIMULATE SNSR 1
SIMULATE SNSR 2*
END SIMUL
BACK TO MENU
EXIT MENU

VIEW CONFIG
SENSOR CONFIG
UNITS
RERANGE
LOOP TEST
DISPLAY

EXTENDED MENU

EXTENDED MENU

EXIT MENU

July 2016

Reference Manual

00809-0100-4728, Rev MB

Using AMS Device Manager

1. Right click on the device and select Service Tools.

2. In the left navigation window select Simulate.

3. In the group box labeled Device Variables choose the variable to simulate.

 Sensor 1 Temperature
 Sensor 2 Temperature (only available with option S)

4. Follow the screen prompts to simulate selected digital value.

Using Local Operator Interface

Reference the figure below to find the path to the Simulate Digital Signal in the LOI menu.

Figure 2-21. Simulating the Digital Signal with LOI

2.11.3 Thermocouple Degradation Diagnostic

36

* Available only if option code (S) is ordered.

Thermocouple Degradation Diagnostic acts as a gauge of the general health of the
thermocouple and is indicative of any major changes in the status of the thermocouple or the
thermocouple loop. The transmitter monitors the resistance of the thermocouple loop to
detect drift conditions or wiring condition changes. The transmitter uses a baseline and
threshold Trigger value and reports the suspected status of the thermocouple based off the
difference between these values. This feature is not intended to be a precise measurement of
thermocouple status, but is a general indicator of thermocouple and thermocouple loop health.

Thermocouple diagnostic must be Enabled as well as connected and configured to read a
thermocouple type sensor. Once the diagnostic has been activated, a Baseline Resistance value
is calculated. Then a Trigger threshold must be selected, which can be two, three, or four times
the Baseline resistance, or the default of 5000 ohms. If the thermocouple loop resistance
reaches the Trigger Level, a maintenance alert is generated.

The Thermocouple Degradation Diagnostic monitors the health of the entire thermocouple
loop, including wiring, terminations, junctions, and the sensor itself. Therefore, it is imperative
that the diagnostic baseline resistance be measured with the sensor fully installed and wired in
the process, and not on the bench.

Configuration

Reference Manual

CALIBRAT
DAMPING
VARIABLE MAP
TAG
ALM SAT VALUES
PASSWORD
SIMULATE
HART REV
HOT BACK CONFIG*
DRIFT ALERT*

TC DIAG CONFIG

TC DIAG CONFIG

MIN MAX TRACK
BACK TO MENU
EXIT MENU

CONFIG SNSR 1CONFIG SNSR 1

CONFIG SNSR 2*
BACK TO MENU
EXIT MENU

VIEW CONFIG
SENSOR CONFIG
UNITS
RERANGE
LOOP TEST
DISPLAY

EXTENDED MENU

EXTENDED MENU

EXIT MENU

SENSOR 1 MODE
TRIGGER CONFIG
TRIGGER VIEW
SNSR OHM VIEW
BASELINE RE-SET
BASELINE VIEW
BACK TO MENU
EXIT MENU

00809-0100-4728, Rev MB

Note

The thermocouple resistance algorithm does not calculate resistance values while the active calibrator
mode is enabled.

Configure T/C Diagnostic with a Field Communicator

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

Configure T/C Diagnostic with AMS Device Manager

1. Right click on the device and select Configure.

2. In the left navigation window select Manual Setup.

3. On the Diagnostics tab, there is a group box labeled Sensor and Process Diagnostics; choose the
button for Configure Thermocouple Diagnostic.

4. Follow the screen prompts to Enable and set the values for the diagnostic.

Glossary of AMS Device Manager terms

Configuration

July 2016

2, 2, 4, 3, 4

Resistance: This is the existing resistance reading of the thermocouple loop.

Resistance Threshold Exceeded: The check box indicates if the sensor resistance has passed the Trigger

Level.

Trigger Level: Threshold resistance value for the thermocouple loop. The Trigger Level may be set for 2,
3, or 4 x baseline or the default of 5000 Ohms. If the resistance of the thermocouple loop surpasses the
Trigger Level, a maintenance alert will be generated.

Baseline Resistance: The resistance of the thermocouple loop obtained after installation, or after
resetting the baseline value. The Trigger Level may be calculated from the baseline Value.

Reset Baseline Resistance: Launches a method to recalculate the baseline value (which may take several
seconds).

TC Diagnostic Mode Sensor 1or 2: This field will read either Enabled or Disabled indicating when the
Thermocouple Degradation Diagnostic is on or off for that sensor.

Configure T/C Diagnostic with the Local Operator Interface

Reference the figure below to find the path to the Thermocouple Diagnostic in the LOI menu.

Figure 2-22. Configuring T/C Diagnostic with LOI

Config uration

* Available only if option code (S) is ordered.

37

Configuration

CALIBRAT
DAMPING
VARIABLE MAP
TAG
ALM SAT VALUES
PASSWORD
SIMULATE
HART REV
HOT BACK CONFIG*
DRIFT ALERT*
TC DIAG CONFIG

MIN MAX TRACK

MIN MAX TRACK

BACK TO MENU
EXIT MENU

VIEW CONFIG
SENSOR CONFIG
UNITS
RERANGE
LOOP TEST
DISPLAY

EXTENDED MENU

EXTENDED MENU

EXIT MENU

MIN-MAX MODE
PARAM CONFIG
VIEW VALUES
RESET VALUES
BACK TO MENU
EXIT MENU

July 2016

2.11.4 Min/Max Tracking diagnostic

Minimum and Maximum Temperature Tracking (Min/Max Tracking) when enabled records minimum and
maximum temperatures with date and time stamps on Rosemount 644 HART Head mount Temperature
Transmitters. This feature records values for Sensor 1, Sensor 2, Differential, Average, First Good and
Terminal temperatures. Min/Max Tracking only records temperature maxima and minima obtained since
the last reset, and is not a logging function.

To track maximum and minimum temperatures, Min/Max Tracking must be enabled using a Field
Communicator, AMS Device Manager, Local Operator Interface, or other communicator. While enabled,
this feature allows for a reset of information at any time, and all variables can be reset simultaneously.
Additionally, each of the individual parameter’s minimum and maximum values may be reset
individually. Once a particular field has been reset, the previous values are overwritten.

Using a Field Communicator

From the HOME screen, enter the Fast Key sequence

Reference Manual

00809-0100-4728, Rev MB

Device Dashboard Fast Keys

2, 2, 4, 3, 5

Using AMS Device Manager

1. Right click on the device and select Configure.

2. In the left navigation window select Manual Setup.

3. On the Diagnostics tab, there is a group box labeled Sensor and Process Diagnostics; choose the
button for Configure Min/Max Tracking.

4. Follow the screen prompts to Enable and configure the settings for the diagnostic.

Using Local Operator Interface

Reference the figure below to find the path to the Thermocouple Diagnostic in the LOI menu.

Figure 2-23. Configuring Min/Max Tracking with LOI

38

* Available only if option code (S) is ordered.

Configuration

Reference Manual

A.

B.

C.

D.

E.

F.

G.

H.

00809-0100-4728, Rev MB

2.12 Establishing multidrop communication

Multidropping refers to the connection of several transmitters to a single communications transmission
line. Communication between the host and the transmitters takes place digitally with the analog output
of the transmitters deactivated.

Many Rosemount transmitters can be multidropped. With the HART communications protocol, up to 15
transmitters can be connected on a single twisted pair of wires or over leased phone lines.

A Field Communicator can test, configure, and format a multidropped Rosemount 644 Transmitter in
the same way as in a standard point-to-point installation. The application of a multidrop installation
requires consideration of the update rate necessary from each transmitter, the combination of
transmitter models, and the length of the transmission line. Each transmitter is identified by a unique
address (1–15) and responds to the commands defined in the HART protocol. A HART-based
communicator can test, configure, and format a multidropped Rosemount 644 Transmitter the same as
in a standard point-to-point installation.

Note

Multidrop is not suitable for safety-certified applications and installations.

Configuration

July 2016

Figure 2-24. Typical Multidropped Network

A. Power supply
B. Power supply impedance
C. 250 
D. Handheld terminal
E. Computer or DCS
F. HA RT Inter fa ce
G. 4-20 mA
H. Rosemount 644 HART Transmitter

Note

Rosemount 644 Transmitters are set to address 0 at the factory, allowing them to operate in the
standard point-to-point manner with a 4–20 mA output signal. To activate multidrop communication,
the transmitter address must be changed to a number between 1 and 15. This change deactivates the 4–
20 mA analog output, sending it to 4 mA. The failure mode current also is disabled.

Config uration

39

Configuration

July 2016

2.12.1 Changing a transmitter address

To activate multidrop communication, the transmitter poll address must be assigned a number from 1
to 15 for HART Revision 5, and 1-63 for HART Revision 7. Each transmitter in a multidropped loop must
have a unique poll address.

Using a Field Communicator

From the HOME screen, enter the Fast Key sequence

Reference Manual

00809-0100-4728, Rev MB

Device Dashboard Fast Keys

1, 2, 1

Using AMS Device Manager

1. Right click on the device and select Configuration Properties from the menu.

2. In HART Revision 5 mode:

a. In the HART tab, enter poll address into the Polling Address box, click Apply.

3. In HART Revision 7 mode:

a. In the HART tab, click the Change Polling Address button.

2.13 Using the transmitter with the HART Tri-Loop

To prepare the Rosemount 644 Transmitter with dual-sensor option for use with a Rosemount 333 HART
Tri-Loop, the transmitter must be configured to Burst Mode and the process variable output order must
be set. In Burst Mode, the transmitter provides digital information for the four process variables to the
HART Tri-Loop. The HART Tri-Loop divides the signal into separate 4–20 mA loops for up to three of the
following choices:

 Primary Variable (PV)
 Secondary Variable (SV)
 Ter tiar y Vari able (Q V)
 Quaternary Variable (QV)

40

When using the Rosemount 644 Transmitter with dual-sensor option in conjunction with the HART
Tri-Loop, consider the configuration of the differential, average, first good temperatures, Sensor Drift
Alert, and Hot Backup features (if applicable).

Note

The procedures are to be used when the sensors and transmitters are connected, powered, and
functioning properly. Also, a Field Communicator must be connected and communicating to the
transmitter control loop. For communicator usage instructions, see “Configuring with a Field

Communicator” on page 10.

Configuration

Reference Manual

00809-0100-4728, Rev MB

2.13.1 Set the transmitter to Burst Mode

To set the transmitter to burst mode, follow the steps below with the Fast Key sequence:

Using a Field Communicator

Configuration

July 2016

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

Using AMS Device Manager

1. Right click on the device and select Configure.

2. In the left navigation window select Manual Setup.

3. On the HART tab find the Burst Mode Configuration group box and fill in the necessary content.

4. Click Apply when complete.

2.13.2 Set process variable output order

To set the process variable output order, follow the steps in one of the methods outlined in “Mapping the

HART variables” on page 15 .

Note

Take careful note of the process variable output order. The HART Tri-Loop must be configured to read the
variables in the same order.

Special considerations

To initiate operation between a Rosemount 644 Transmitter with dual-sensor option and the HART
Tri-Loop, consider the configuration of both the differential, average and first good temperatures, Sensor
Drift Alert, and Hot Backup features (if applicable).

HART 5 HART 7

2, 2, 8, 4 2, 2, 8, 5

Config uration

Differential temperature measurement

To enable the differential temperature measurement feature of a dual-sensor Rosemount 644 operating
in conjunction with the HART Tri-Loop, adjust the range end points of the corresponding channel on the
HART Tri-Loop to include zero. For example, if the secondary variable is to report the differential
temperature, configure the transmitter accordingly (see “Mapping the HART variables” on page 15) and
adjust the corresponding channel of the HART Tri-Loop so one range end point is negative and the other
is positive.

Hot Backup

To enable the Hot Backup feature of a Rosemount 644 Transmitter with dual-sensor option operating in
conjunction with the HART Tri-Loop, ensure that the output units of the sensors are the same as the units
of the HART Tri-Loop. Use any combination of RTDs or thermocouples as long as the units of both match
the units of the HART Tri-Loop.

Using the Tri-Loop to detect sensor drift alert

The dual-sensor Rosemount 644 Transmitter sets a failure flag (through HART) whenever a sensor failure
occurs. If an analog warning is required, the HART Tri-Loop can be configured to produce an analog
signal that can be interpreted by the control system as a sensor failure.

Use these steps to set up the HART Tri-Loop to transmit sensor failure alerts.

41

Configuration

3 °C
0 °C

–3 °C

100 °C

Sensor Drift

Sensor Drift

Sensor Failure

(Failure Mode Switch HIGH)

DIFFERENTIAL

TEM PE RA TU RE

Sensor Failure

(Failure Mode Switch LOW)

–100 °C

July 2016

Reference Manual

00809-0100-4728, Rev MB

1. Configure the dual-sensor Rosemount 644 variable map as shown.

Variable Mapping

PV Sensor 1 or Sensor Average

SV Sensor 2

TV Differential Temperature

QV As Desired

2. Configure Channel 1 of the HART Tri-Loop as TV (differential temperature). If either sensor should fail,
the differential temperature output will be +9999 or –9999 (high or low saturation), depending on
the position of the Failure Mode Switch (see “Alarm Switch (HART)” on page 15).

3. Select temperature units for Channel 1 that match the differential temperature units of the
transmitter.

4. Specify a range for the TV such as –100 to 100 °C. If the range is large, then a sensor drift of a few
degrees will represent only a small percent of range. If Sensor 1 or Sensor 2 fails, the TV will be +9999
(high saturation) or –9999 (low saturation). In this example, zero is the midpoint of the TV range. If a
T of zero is set as the lower range limit (4 mA), then the output could saturate low if the reading
from Sensor 2 exceeds the reading from Sensor 1. By placing a zero in the middle of the range, the
output will normally stay near 12 mA, and the problem will be avoided.

5. Configure the DCS so that TV  –100 °C or TV  100 °C indicates a sensor failure and, for example,
TV –3 °C or TV  3 °C indicates a drift alert. See Figure 2-25.

Figure 2-25. Tracking Sensor Drift and Sensor Failure with Differential Temperature

42

Configuration

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00809-0100-4728, Rev MB

Section 3 Hardware Installation

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 43

Safety messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 43

Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 44

Installation procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 45

Note

Each transmitter is marked with a tag indicating the approvals. Install the transmitter according to all
applicable installation codes, and approval and installation drawings (see Appendix Appendix B Product

Certifications). Verify the operating atmosphere of the transmitter is consistent with the hazardous

location certifications. Once a device labeled with multiple approval types is installed, it should not be
reinstalled using any of the other labeled approval types. To ensure this, the approval label should be
permanently marked to distinguish the approval type(s) used.

Hardware Installation

July 2016

3.1 Overview

The information in this section covers installation considerations for the Rosemount™ 644 Temperature
Transmitter with HART

with every transmitter to describe recommended mounting and wiring procedures for initial installation.
Dimensional drawings for Rosemount 644 mounting configurations are included in Appendix A:

Specifications and Reference Data.

®

protocol. A Quick Start Guide (document number 00825-0200-4728) is shipped

3.2 Safety messages

Instructions and procedures in this section may require special precautions to ensure the safety of the
personnel performing the operations. Information that potentially raises safety issues is indicated by a

warning symbol ( ). Refer to the following safety messages before performing an operation preceded
by this symbol.

Hardware Installation

43

Hardware Installation

July 2016

Failure to follow these installation guidelines could result in death or serious injury.

 Make sure only qualified personnel perform the installation.

Explosions could result in death or serious injury.

 Do not remove the connection head cover in explosive atmospheres when the circuit is live.
 Before connecting a Field Communicator in an explosive atmosphere, make sure the instruments in

the loop are installed in accordance with intrinsically safe or non-incendive field wiring practices.

 Verify the operating atmosphere of the transmitter is consistent with the appropriate hazardous

locations certifications.

 All connection head covers must be fully engaged to meet explosion-proof requirements.

Process leaks could result in death or serious injury.

 Do not remove the thermowell while in operation.
 Install and tighten thermowells and sensors before applying pressure.

Electrical shock could cause death or serious injury.

 Use extreme caution when making contact with the leads and terminals.

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3.3 Considerations

3.3.1 Installation considerations

Measurement accuracy depends upon proper installation of the transmitter. Mount the transmitter close
to the process and use minimum wiring to achieve best accuracy. Keep in mind the need for easy access,
personnel safety, practical field calibration, and a suitable transmitter environment. Install the
transmitter to minimize vibration, shock, and temperature fluctuation.

3.3.2 Environmental considerations

Best practice is to mount the transmitter in an environment that has minimal ambient temperature
change. The transmitter electronics temperature operating limits are –40 to 185 °F (–40 to 85 °C). Refer
to Appendix A: Specifications and Reference Data for sensing element operating limits. Mount the
transmitter so it is not susceptible to vibration and mechanical shock and does not have external contact
with corrosive materials.

44

Hardware Installation

Reference Manual

START

HERE

Bench

Calibration?

BASIC SETUP

Set Sensor Type

Set Number of Wires

Set Units

Set Range Values

Set Damping

VERIFY

Simulate Sensor Input

Within

Specifications?

FIELD INSTALL

Set Failure Mode Switch

Mount Transmitter

Wire Transmitter

Power Transmitter

FINISHED

00809-0100-4728, Rev MB

3.4 Installation procedures

Figure 3-1. Installation Flowchart

Hardware Installation

July 2016

3.4.1 Set the alarm switch

Make sure the alarm switch is set to the desired position before putting the device into operation to
ensure correct function in the instance of a failure.

Without an LCD display

1. Set the loop to manual (if applicable) and disconnect the power.

2. Remove the housing cover.

3. Set the physical hardware alarm switch to the desired position. H indicates High, L indicates Low.
Then reattach the housing cover. See Figure 3-2 below for alarm switch location.

Hardware Installation

4. Apply power and set the loop to automatic control.

45

Hardware Installation

L

H

July 2016

Figure 3-2. Failure Switch Location

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00809-0100-4728, Rev MB

Note

If using an LCD display or Local Operator Interface, first remove the display by detaching it from the top
of the Rosemount 644 device, set the switch to the desired position and reattach the display. See

Figure 3-3. for proper display orientation.

Figure 3-3. Display Connection

3.4.2 Mount the transmitter

Mount the transmitter at a high point in the conduit run to prevent moisture from draining into the
transmitter housing.

The Rosemount 644 head mount installs:

 In a connection head or universal head mounted directly on a sensor assembly
 Apart from a sensor assembly using a universal head
 To a DIN rail using an optional mounting clip

The Rosemount 644 rail mount attaches directly to a wall or to a DIN rail.

46

Hardware Installation

Reference Manual

A

B

C

00809-0100-4728, Rev MB

Mounting a Rosemount 644 to a DIN Rail

To attach a head mount transmitter to a DIN rail, assemble the appropriate rail mounting kit (part
number 00644-5301-0010) to the transmitter as shown in Figure 3-4. Follow the procedure under “Rail

mount transmitter and sensor”.

Figure 3-4. Assembling Rail Clip Hardware to a Rosemount 644

Hardware Installation

July 2016

G-Rail (asymmetric) Top Hat Rail (symmetric)

A

B

C

Note: Kit (part number 00644-5301-0010) includes mounting hardware and both types of rail kits.

A. Mounting hardware
B. Transmitter
C. Rail clip

3.4.3 Install the device

Typical connection head installation–head mount transmitter with
DIN plate style sensor

1. Attach the thermowell to the pipe or process container wall. Install and tighten the thermowell before
applying process pressure.

2. Verify the transmitter failure mode switch position.

3. Assemble the transmitter to the sensor
mounting plate.

4. Wire the sensor to the transmitter (see “Wiring and powering the transmitter” on page 53).

5. Insert the transmitter-sensor assembly into the connection head. Thread the transmitter mounting
screw into the connection head mounting holes. Assemble the extension to the connection head by
tightening the threaded connections of the extension to the housing. Insert the assembly into the
thermowell and tighten the threaded connections.

(1)

. Push the transmitter mounting screws through the sensor

6. If using a cable gland for power wiring, properly attach the cable gland to a housing conduit entry.

7. Insert the shielded cable leads into the connection head through the conduit entry.

1, If using a threaded type sensor with a connection head, Reference steps in “Wiring and powering the transmitter” on page 53.

Hardware Installation

47

Hardware Installation

July 2016

8. Connect the shielded power cable leads to the transmitter power terminals. Avoid contact with
sensor leads and sensor connections. Connect and tighten the cable gland.

9. Install and tighten the connection head cover. Enclosure covers must be fully engaged to meet
explosion-proof requirements.

Reference Manual

00809-0100-4728, Rev MB

A

E

D

A. Connection head cover D. Rosemount 644 Transmitter
B. Connection head E. Integral mount sensor with flying leads
C. Thermowell F. Extension

B

C

F

Typical Universal Head Installation–head mount transmitter with
threaded sensor

1. Attach the thermowell to the pipe or process container wall. Install and tighten thermowells before
applying process pressure.

2. Attach necessary extension nipples and adapters to the thermowell. Seal the nipple and adapter
threads with silicone tape.

3. Screw the sensor into the thermowell. Install drain seals if required for severe environments or to
satisfy code requirements.

4. Verify the transmitter failure mode switch is in the desired position.

5. Pull the sensor wiring leads through the universal head and transmitter. Mount the transmitter in the
universal head by threading the transmitter mounting screws into the universal head mounting holes.

6. Seal adapter threads with thread sealant.

7. Pull the field wiring leads through the conduit into the universal head. Wire the sensor and power
leads to the transmitter (see “Wiring and powering the transmitter” on page 64). Avoid contact with
other terminals.

8. Install and tighten the universal head cover. Enclosure covers must be fully engaged to meet
explosion-proof requirements.

48

Hardware Installation

Reference Manual

A

B

C

D

E

B

C

D

E

F

A

B

00809-0100-4728, Rev MB

A. Rosemount 644 Transmitter D. Extension
B. Universal junction box E. Threaded thermowell
C. Threaded style sensor

Rail mount transmitter and sensor

1. Attach the transmitter to a suitable rail or panel.

2. Attach the thermowell to the pipe or process container wall. Install and tighten the thermowell,
according to plant standards, before applying pressure.

Hardware Installation

July 2016

3. Attach the sensor to the connection head and mount the entire assembly to the thermowell.

4. Attach and connect sufficient lengths of sensor lead wire from the connection head to the sensor
terminal block.

5. Tighten the connection head cover. Enclosure covers must be fully engaged to meet explosion-proof
requirements.

6. Run sensor lead wires from the sensor assembly to the transmitter.

7. Verify the transmitter failure mode switch.

8. Attach the sensor wires to the transmitter.

A. Rail mount transmitter
B. Sensor leads with cable Glands
C. Integral mount sensor with terminal block
D. Connection head
E. Standard extension
F. Threaded thermowell

Hardware Installation

49

Hardware Installation

A

D

E

C

B

July 2016

Rail mount transmitter with threaded sensor

1. Attach the transmitter to a suitable rail or panel.

2. Attach the thermowell to the pipe or process container wall. Install and tighten the thermowell before
applying pressure.

3. Attach necessary extension nipples and adapters. Seal the nipple and adapter threads with thread
sealant.

4. Screw the sensor into the thermowell. Install drain seals if required for severe environments or to
satisfy code requirements.

5. Screw the connection head to the sensor.

6. Attach the sensor lead wires to the connection head terminals.

7. Attach additional sensor lead wires from the connection head to the transmitter.

8. Attach and tighten the connection head cover. Enclosure covers must be fully engaged to meet
explosion-proof requirements.

9. Set the transmitter failure mode switch.

10.Attach the sensor wires to the transmitter.

Reference Manual

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A. Rail mount transmitter D. Threaded style sensor
B. Threaded sensor connection head E. Threaded thermowell
C. Standard extension

50

Hardware Installation

Reference Manual

A

B

R

Lead

R

Lead

R

Lead

C

D

To Additional
Tra ns m it te rs

F

E

Between 250  and 1100  if no load resistor.

A

B

C

D

00809-0100-4728, Rev MB

3.4.4 Multichannel installations

In a HART installation, several transmitters can be connected to a single master power supply, as shown
in Figure 3-5. In this case, the system may be grounded only at the negative power supply terminal. In
multichannel installations where several transmitters depend on one power supply and the loss of all
transmitters would cause operational problems, consider an uninterrupted power supply or a back-up
battery. The diodes shown in Figure 3-5 prevent unwanted charging or discharging of the
back-up battery.

Figure 3-5. Multichannel Installations

Hardware Installation

July 2016

A. Transmitter number 1
B. Transmitter number 2
C. Readout or controller number 1

3.4.5 LCD display Installation

The LCD display provides local indication of the transmitter output and abbreviated diagnostic messages
governing transmitter operation. Transmitters ordered with the LCD display are shipped with the meter
installed. After-market installation of the meter can be performed. After-market installation requires the
meter kit (part number 00644-7630-0011), which includes:

 LCD display assembly (includes LCD display, meter spacer, and 2 screws)
 Meter cover with O-ring in place

Figure 3-6. Installing the LCD Display

D. Readout or controller number 2
E. Backup battery
F. dc power supply

A. Rosemount 644 Transmitter

Hardware Installation

B. Mounting screws and springs
C. LCD display
D. LCD display rotation screws

51

Hardware Installation

July 2016

Use the following procedure to install the meter.

1. If the transmitter is installed in a loop, secure the loop and disconnect the power. If the transmitter is
installed in an enclosure, remove the cover from the enclosure.

2. Decide meter orientation (the meter can be rotated in 90° increments). To change meter orientation,
remove the screws located above and below the display screen. Lift the meter off the meter spacer.
Rotate the display top and re-insert it in the location that will result in the desired viewing orientation.

3. Reattach the meter to the meter spacer using the screws. If the meter was rotated 90 degrees from its
original position it will be necessary to remove the screws from their original holes and re-insert them
in the adjacent screws holes.

4. Line up the connector with the pin socket and push the meter into the transmitter until it snaps into
place.

5. Attach the meter cover. The cover must be fully engaged to meet explosion-proof requirements.

6. Use a Field Communicator, AMS software tool to configure the meter to the desired display. Refer to

“LCD Meter Options ( 644H Only)” for information on configuring the LCD display.

Note

Observe the following LCD display temperature limits:
Operating: –4 to 185 °F (–20 to 85 °C)
Storage: –50 to 185 °F (–45 to 85 °C)

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52

Hardware Installation

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Section 4 Electrical Installation

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 53

Safety messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 53

Wiring and powering the transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 53

4.1 Overview

The information in this section covers installation considerations for the Rosemount 644 Transmitter. A
Quick Start Guide is shipped with every transmitter to describe mounting, wiring, and basic
configuration procedures for initial installation.

4.2 Safety messages

Electrical Installation

July 2016

Instructions and procedures in this section may require special precautions to ensure the safety of the
personnel performing the operations. Information that potentially raises safety issues is indicated by a

warning symbol ( ). Refer to the following safety messages before performing an operation preceded
by this symbol.

Explosions could result in death or serious injury

Installation of this transmitter in an explosive environment must be in accordance with the appropriate
local, national, and international standards, codes, and practices. Review the approvals section of the
Rosemount 644 Reference Manual for any restrictions associated with a safe installation.

 In an Explosion-Proof/Flameproof installation, do not remove the transmitter covers when power is

applied to the unit.

Process leaks may cause harm or result in death.

 Install and tighten process connectors before applying pressure.

Electrical shock can result in death or serious injury.

 Avoid contact with the leads and terminals. High voltage that may be present on leads can cause

electrical shock.

4.3 Wiring and powering the transmitter

Electrical Installation

All power to the transmitter is supplied over the signal wiring. Use ordinary copper wire of sufficient size
to ensure that the voltage across the transmitter power terminals does not drop below 12.0 Vdc.

If the sensor is installed in a high-voltage environment and a fault condition or installation error occurs,
the sensor leads and transmitter terminals could carry lethal voltages. Use extreme caution when
making contact with the leads and terminals.

53

Electrical Installation

A

B

C

July 2016

Note

Do not apply high voltage (e.g. ac line voltage) to the transmitter terminals. Abnormally high voltage
can damage the unit (sensor and transmitter power terminals are rated to 42.4 Vdc. A constant 42.4
volts across the sensor terminals may damage the unit).

For multichannel HART installations, see above. The transmitters will accept inputs from a variety of RTD
and thermocouple types. Refer to Figure 2-6 on page 17 when making sensor connections.

The sensor Wiring Diagram is located on the device’s top label below the terminal screws. See Figure 4-1
and Figure 4-2 for where to find and how to correctly wire all sensor types to the Rosemount 644
Tr an sm i tt er.

Figure 4-1. Wiring Diagram Location

Rosemount 644H – single input Rosemount 644S – dual inputs

Reference Manual

00809-0100-4728, Rev MB

A. Sensor terminals
B. Single input wiring diagram
C. Power terminals

4.3.1 Sensor connections

The Rosemount 644 is compatible with a number of RTD and thermocouple sensor types. Figure 4-2
shows the correct input connections to the sensor terminals on the transmitter. To ensure a proper
sensor connection, anchor the sensor lead wires into the appropriate captive terminals and tighten the
screws.

Figure 4-2. Sensor Wiring

A

A. Sensor terminals
B. Dual input wiring diagram
C. Power terminals

B

C

*The transmitter must be configured for at least a 3-wire RTD in order to recognize an RTD with a compensation loop.

54

** Emerson

™

unneeded leads disconnected and insulated with electrical tape.

Process Management provides a 4-wire sensors for all single element RTDs. Use these RTDs in 3-wire configurations by leaving the

Electrical Installation

Reference Manual

00809-0100-4728, Rev MB

Thermocouple or millivolt inputs

The thermocouple can be connected directly to the transmitter. Use appropriate thermocouple
extension wire if mounting the transmitter remotely from the sensor. Make millivolt inputs connections
with copper wire. Use shielding for long runs of wire.

RTD or ohm inputs

The transmitters will accept a variety of RTD configurations, including 2-, 3- or 4-wire. If the transmitter
is mounted remotely from a 3- or 4-wire RTD, it will operate within specifications, without recalibration,
for lead wire resistances of up to 60 ohms per lead (equivalent to 6,000 feet of 20 AWG wire). In this case,
the leads between the RTD and transmitter should be shielded. If using only two leads, both RTD leads
are in series with the sensor element, so significant errors can occur if the lead lengths exceed three feet
of 20 AWG wire (approximately 0.05 °C/ft). For longer runs, attach a third or fourth lead as described
above.

Sensor lead wire resistance effect– RTD input

When using a 4-wire RTD, the effect of lead resistance is eliminated and has no impact on accuracy.
However, a 3-wire sensor will not fully cancel lead resistance error because it cannot compensate for
imbalances in resistance between the lead wires. Using the same type of wire on all three lead wires will
make a 3-wire RTD installation as accurate as possible. A 2-wire sensor will produce the largest error
because it directly adds the lead wire resistance to the sensor resistance. For 2- and 3-wire RTDs, an
additional lead wire resistance error is induced with ambient temperature variations. The table and the
examples shown below help quantify these errors.

Electrical Installation

July 2016

Note

For HART transmitters, the use of two grounded thermocouples with a dual option Rosemount 3144P
Transmitter is not recommended. For applications in which the use of two thermocouples is desired,
connect either two ungrounded thermocouples, one grounded and one ungrounded thermocouple, or
one dual element thermocouple.

4.3.2 Power the transmitter

1. An external power supply is required to operate the transmitter.

2. Remove the housing cover (if applicable).

3. Connect the positive power lead to the “+” terminal. Connect the negative power lead to the “–”
terminal.

4. Tighten the terminal screws. When tightening the sensor and power wires, the max torque is 6.5
in.-lbs (0.73 N-m).

5. Reattach and tighten the cover (if applicable).

Electrical Installation

55

Electrical Installation

31 (1.2)

36

(1.4)

104

(4.1)

82

(3.2)

Sensor
Ter mi na l s

Power
Ter mi na l s

July 2016

6. Apply power (12 – 42 Vdc).

HART device shown with captivated screw terminals

Rosemount 644 (DIN A Head Mount)

60 (2.4)

Sensor Terminals

Display
Connection

33 (1.3)

Reference Manual

00809-0100-4728, Rev MB

Communication
Terminals

59 (2.3)

24 (.96)

Failure
Mode Switch

Dimensions are in millimeters (inches).

Power Terminals

Rosemount 644 Rail Mount

56

Electrical Installation

Reference Manual

Field Communicator

250 V R

L

 1100 V

Power

Supply

00809-0100-4728, Rev MB

Powering the transmitter for bench configuration

Rosemount 644 Head mount Rosemount 644 Rail mount

Signal loop may be grounded at any point or left ungrounded.

A Field Communicator may be connected at any termination point in the signal loop. The signal loop
must have between 250 and 1100 ohms load for communications.

Max torque is 6 in.-lbs (0/7 N-m).

Electrical Installation

July 2016

Load limitation

The power required across the transmitter power terminals is 12 to 42.4 Vdc (the power terminals are
rated to 42.4 Vdc). To prevent damaging the transmitter, do not allow terminal voltage to drop below

12.0 Vdc when changing the configuration parameters.

4.3.3 Ground the transmitter

Sensor shielding

The currents in the leads induced by electromagnetic interference can be reduced by shielding. Shielding
carries the current to ground and away from the leads and electronics. If the ends of the shields are
adequately grounded, only a small amount of current will actually enter the transmitter. If the ends of
the shield are left ungrounded, voltage is created between the shield and the transmitter housing and
also between the shield and earth at the element end. The transmitter may not be able to compensate
for this voltage, causing it to lose communication and/or go into alarm. Instead of the shield carrying the
currents away from the transmitter, the currents will now flow through the sensor leads into the
transmitter circuitry where it will interfere with the circuit operation.

Shielding recommendations

The following are recommended practices from API Standard 552 (Transmission Standard) section 20.7,
and from field and laboratory testing. If more than one recommendation is given for a sensor type, start
with the first technique shown or the technique that is recommended for the facility by its installation
drawings. If the technique does not eliminate the transmitter alarms, try another technique. If all of the
techniques do not eliminate or prevent the transmitter alarms because of high EMI, contact an Emerson
Process Management representative.

Electrical Installation

To ensure proper grounding, it is important that the instrument cable shield be:

 Trimmed close and insulated from touching the transmitter housing
 Connected to the next shield if cable is routed through a junction box
 Connected to a good earth ground at the power supply end

57

Electrical Installation

July 2016

Ungrounded thermocouple, mV, and RTD/ohm inputs

Each process installation has different requirements for grounding. Use the grounding options
recommended by the facility for the specific sensor type, or begin with grounding Option 1: (the most
common).

Option 1

1. Connect sensor wiring shield to the transmitter housing.

2. Ensure the sensor shield is electrically isolated from surrounding fixtures that may be grounded.

3. Ground signal wiring shield at the power supply end.

Reference Manual

00809-0100-4728, Rev MB

Option 2

1. Connect signal wiring shield to the sensor wiring shield.

2. Ensure the two shields are tied together and electrically isolated from the transmitter housing.

3. Ground shield at the power supply end only.

4. Ensure the sensor shield is electrically isolated from the surrounding grounded fixtures.

5. Connect shields together, electrically isolated from the transmitter.

58

Electrical Installation

Reference Manual

00809-0100-4728, Rev MB

Option 3

1. Ground sensor wiring shield at the sensor, if possible.

2. Ensure that the sensor wiring and signal wiring shields are electrically isolated from the transmitter
housing.

3. Do not connect the signal wiring shield to the sensor wiring shield.

4. Ground signal wiring shield at the power supply end.

Electrical Installation

July 2016

Grounded thermocouple inputs

Option 1

1. Ground sensor wiring shield at the sensor.

2. Ensure the sensor wiring and signal wiring shields are electrically isolated from the transmitter
housing.

3. Do not connect the signal wiring shield to the sensor wiring shield.

4. Ground signal wiring shield at the power supply end.

Electrical Installation

59

Electrical Installation

1240

1000

750

250

0

10

12.0

20 30 40 42.4

Supply Voltage (Vdc)

Operating

Region

4–20 mA dc

Load (Ohms)

500

1100

July 2016

Reference Manual

00809-0100-4728, Rev MB

4.3.4 Wiring with a Rosemount 333 HART Tri-Loop™ (HART / 4–20 mA
only)

Use the dual-sensor option Rosemount 644 Transmitter that is operating with two sensors in
conjunction with a Rosemount 333 HART Tri-Loop HART-to-Analog Signal Converter to acquire an
independent 4–20 mA analog output signal for each sensor input. The Rosemount 644 Transmitter can
be configured to output four of the six following digital process variables:

 Sensor 1
 Sensor 2
 Differential temperature
 Average temperature
 First good temperature
 Transmitter terminal temperature

The HART Tri-Loop reads the digital signal and outputs any or all of these variables into as many as three
separate 4–20 mA analog channels. Refer to Figure 2-6 on page 17 for basic installation information.
Refer to the Rosemount 333 HART Tri-Loop HART-to-Analog Signal Converter Reference Manual
(document number 00809-0100-4754) for complete installation information.

Power supply

An external power supply is required to operate the Rosemount 644 and is not included. The input
voltage range of the transmitter is 12 to 42.4 Vdc. This is the power required across the transmitter
power terminals. The power terminals are rated to 42.4 Vdc. With 250 ohms of resistance in the loop,
the transmitter requires a minimum of 18.1 Vdc for communication.

The power supplied to the transmitter is determined by the total loop resistance and should not drop
below the lift-off voltage. The lift-off voltage is the minimum supply voltage required for any given total
loop resistance. If the power drops below the lift-off voltage while the transmitter is being configured,
the transmitter may output incorrect information.

The dc power supply should provide power with less than 2% ripple. The total resistance load is the sum
of the resistance of the signal leads and the load resistance of any controller, indicator, or related piece of
equipment in the loop. Note that the resistance of intrinsic safety barriers, if used, must be included.

Note

Permanent damage to the transmitter could result if the voltage drops below 12.0 Vdc at the power
terminals, when changing transmitter configuration parameters.

Figure 4-3. Load Limits

Maximum Load = 40.8 X (Supply Voltage - 12.0)

60

Electrical Installation

Reference Manual

00809-0100-4728, Rev MB

Operation and Maintenance

Section 5 Operation and Maintenance

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 61

Safety messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 61

Calibration overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 62

Sensor input trim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 62

Trim the analog output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 65

Transmitter-Sensor Matching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 67

Switching HART Revision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 69

5.1 Overview

July 2016

This section contains information on calibrating Rosemount™ 644 Temperature Transmitter. Field
Communicator, AMS

perform all functions.

™

Device Manager, and Local Operator Interface (LOI) instructions are given to

5.2 Safety messages

Instructions and procedures in this section may require special precautions to ensure the safety of the
personnel performing the operations. Information that potentially raises safety issues is indicated by a

warning symbol ( ). Refer to the following safety messages before performing an operation preceded
by this symbol.

Failure to follow these installation guidelines could result in death or serious injury.

 Make sure only qualified personnel perform the installation.

Explosions could result in death or serious injury.

 Do not remove the connection head cover in explosive atmospheres when the circuit is live.
 Before connecting a Field Communicator in an explosive atmosphere, make sure the instruments

in the loop are installed in accordance with intrinsically safe or non-incendive field wiring
practices.

 Verify the operating atmosphere of the transmitter is consistent with the appropriate hazardous

locations certifications.

 All connection head covers must be fully engaged to meet explosion-proof requirements.

Process leaks could result in death or serious injury.

 Do not remove the thermowell while in operation.
 Install and tighten thermowells and sensors before applying pressure.

Electrical shock could cause death or serious injury.

 Use extreme caution when making contact with the leads and terminals.

Operation and Maintenance

61

Operation and Maintenance

July 2016

5.3 Calibration overview

Calibrating the transmitter increases the measurement precision by allowing corrections to be made to
the factory-stored characterization curve by digitally altering the transmitter’s interpretation of the
sensor input.

To understand calibration, it is necessary to understand that smart transmitters operate differently from
analog transmitters. An important difference is that smart transmitters are factory-characterized,
meaning that they are shipped with a standard sensor curve stored in the transmitter firmware. In
operation, the transmitter uses this information to produce a process variable output, in engineering
units, dependent on the sensor input.

Calibration of the Rosemount 644 may include the following procedures:

 Sensor Input Trim: digitally alter the transmitter’s interpretation of the input signal
 Transmitter Sensor Matching: generates a special custom curve to match that specific sensor curve,

as derived from the Callendar-Van Dusen constants

 Output Trim: calibrates the transmitter to a 4–20 mA reference scale
 Scaled Output Trim: calibrates the transmitter to a user-selectable reference scale.

5.3.1 Trimming

Reference Manual

00809-0100-4728, Rev MB

The trim functions should not be confused with the rerange functions. Although the rerange command
matches a sensor input to a 4–20 mA output—as in conventional calibration—it does not affect the
transmitter’s interpretation of the input.

One or more of the trim functions may be used when calibrating. The trim functions are as follows:

 Sensor Input Trim
 Transmitter-Sensor Matching
 Output Trim
 Output Scaled Trim

5.4 Sensor input trim

The Sensor Trim command allows for alteration of the transmitter’s interpretation of the input signal. The
sensor trim command trims, in engineering (°F, °C, °R, K) or raw (ohms, mV) units, the combined sensor
and transmitter system to a site standard using a known temperature source. Sensor trim is suitable for
validation procedures or for applications that require profiling the sensor and transmitter together.

Perform a sensor trim if the transmitter’s digital value for the primary variable does not match the plant’s
standard calibration equipment. The sensor trim function calibrates the sensor to the transmitter in
temperature units or raw units. Unless the site-standard input source is NIST-traceable, the trim
functions will not maintain the NIST-traceability of your system.

62

Operation and Maintenance

Reference Manual

Resistance (ohms)

Tem pe ra tu re

Resistance (ohms)

Tem pe ra tu re

00809-0100-4728, Rev MB

Figure 5-1. Trim

Application: Linear Offset Application: Linear Offset and Slope Correction
Solution: Single-Point Trim Solution: Two-Point Trim

Method:

1. Connect sensor to transmitter. Place sensor in bath
between range points.

2. Enter known bath temperature using the Field
Communicator.

Operation and Maintenance

July 2016

Method:

1. Connect sensor to transmitter. Place sensor in bath
at low range point.

2. Enter known bath temperature using the Field
Communicator.

3. Repeat at high range point.

One-Point Trim Two-Point Trim

Transmitter System Curve

Site-Standard Curve

Using Field Communicator

Use the following procedures to perform a sensor trim on the Rosemount 644:

1. Connect the calibration device or sensor to the transmitter. (If using an active calibrator, see “Ac ti ve

calibrator and EMF compensation” on page 65)

2. Connect the communicator to the transmitter loop.

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

3, 4, 4, 1

The communicator will ask “Are you using an active calibrator?”

a. Select “No” if a sensor is connected to the transmitter
b. Select “Ye s” if using a calibration device. By selecting yes, the transmitter will switch into active

calibration mode (see “Active Calibrator and EMF Compensation”). This is critical if the calibrator
requires constant sensor current for calibration. If using a calibration device that can accept
pulsed current, select “No.”

Using AMS Device Manager

1. Right click on the device and select Overview.

2. On the main Overview tab, click on the Calibrate Sensor(s) button near the bottom of the window.

3. Follow the screen prompts that will guide you through the sensor trimming process.

Operation and Maintenance

63

Operation and Maintenance

CALIBRATCALIBRAT

DAMPING
VARIABLE MAP
TAG
ALM SAT VALUES
PASSWORD

....

VIEW CONFIG
SENSOR CONFIG
UNITS
RERANGE
LOOP TEST
DISPLAY

EXTENDED MENU

EXTENDED MENU

EXIT MENU

SENSOR 1 CALIBSENSOR 1 CALIB
SENSOR 2 CALIB*SENSOR 2 CALIB*

ANALOG TRIM
FACTORY RECALL
BACK TO MENU
EXIT MENU

....

CALIBRATCALIBRAT

DAMPING
VARIABLE MAP
TAG
ALM SAT VALUES
PASSWORD

....

VIEW CONFIG
SENSOR CONFIG
UNITS
RERANGE
LOOP TEST
DISPLAY

EXTENDED MENU

EXTENDED MENU

EXIT MENU

SENSOR 1 CALIB
SENSOR 2 CALIB*
ANALOG TRIM

FACTORY RECALL

FACTORY RECALL

BACK TO MENU
EXIT MENU

....

July 2016

Using the Local Operator Interface

Reference the below image for guidance on where to find Sensor Calibration in the LOI menu.

Figure 5-2. Trimming the Sensor with the LOI

5.4.1 Recall Factory Trim—Sensor trim

Th e Rec all Fac tory Trim—Sensor Trim feature a llows the restoration of the as-shipped factory settings of
the analog output trim. This command can be useful for recovering from an inadvertent trim, incorrect
plant standard or faulty meter.

Reference Manual

00809-0100-4728, Rev MB

Using Field Communicator

From the HOME screen, enter the Fast Key sequence and follow the steps within the Field Communicator to
complete the Sensor Trim.

Device Dashboard Fast Keys

3, 4, 4, 2

Using AMS Device Manager

1. Right click on the device and select Service Tools.

2. On the Sensor Calibration tab, click on the Restore Factory Calibration.

3. Follow the screen prompts that will guide you through the restoring of the calibration settings.

Using the Local Operator Interface

Reference the below image for where to find Recall Sensor Trim in the LOI menu.

Figure 5-3. Recalling the Sensor Trim with the LOI

64

Operation and Maintenance

Reference Manual

Microprocessor

Digital-to-Analog

Signal Conversion

Analog-to-Digital Signal

Conversion

Transmitter Electronics Module

Analog Input

Analog

Output

Field

Communicator

HART

Output

Sensor and Ohm/mV
Trim adjust the signal here

Output and Scaled Output Trim
adjust the signal here

00809-0100-4728, Rev MB

5.4.2 Active calibrator and EMF compensation

The transmitter operates with a pulsating sensor current to allow EMF compensation and detection of
open sensor conditions. Because some calibration equipment requires a steady sensor current to
function properly, the Active Calibrator Mode feature should be used when an active calibrator is
connected. Enabling this mode temporarily sets the transmitter to provide steady sensor current unless
two sensor inputs are configured.

Disable this mode before putting the transmitter back into the process to set the transmitter back to
pulsating current. Active Calibrator Mode is volatile and will automatically be disabled when a master reset
is performed (through HART) or when the power is cycled.

EMF compensation allows the transmitter to provide sensor measurements that are unaffected by
unwanted voltages, typically due to thermal EMFs in the equipment connected to the transmitter, or by
some types of calibration equipment. If this equipment also requires steady sensor current, the
transmitter must be set to Active Calibrator Mode. However, the steady current does not allow the
transmitter to perform EMF compensation and as a result, a difference in readings between the active
calibrator and actual sensor may exist.

If a reading difference is experienced and is greater than the plant’s accuracy specification allows,
perform a sensor trim with Active Calibrator Mode disabled. In this case, an active calibrator capable of
tolerating pulsating sensor current must be used or the actual sensors must be connected to the
transmitter. When the Field Communicator, AMS Device Manager or the LOI asks if an active calibrator is
being used when the sensor trim routine is entered, select No to leave the Active Calibrator Mode
disabled.

Operation and Maintenance

July 2016

5.5 Trim the analog output

5.5.1 Analog output trim or Scaled Analog Output Trim

Perform an Output Trim or a Scaled Output Trim if the digital value for the primary variable matches the
plant’s standards but the transmitter’s analog output does not match the reading on the output device.
The output trim function calibrates the transmitter to a 4–20 mA reference scale; the scaled output trim
function calibrates to a user-selectable reference scale. To determine the need for an output trim or a
scaled output trim, perform a loop test (“Performing a loop test” on page 39).

Figure 5-4. Measurement Dynamics of a Smart Temperature transmitter

5.5.2 Analog output trim

The Analog Output Trim allows the transmitter’s conversion of the input signal to a 4–20 mA output to

Operation and Maintenance

be altered (Figure 5-4). Adjust the analog output signal at regular intervals to maintain measurement
precision. To perform a digital-to-analog trim, perform the following procedure with Traditional Fast Key
sequence:

65

Operation and Maintenance

CALIBRATCALIBRAT

DAMPING
VARIABLE MAP
TAG
ALM SAT VALUES
PASSWORD

....

VIEW CONFIG
SENSOR CONFIG
UNITS
RERANGE
LOOP TEST
DISPLAY

EXTENDED MENU

EXTENDED MENU

EXIT MENU

SENSOR 1 CALIB
SENSOR 2 CALIB*

ANALOG TRIM

ANALOG TRIM

FACTORY RECALL
BACK TO MENU
EXIT MENU

....

July 2016

Using Field Communicator

1. Connect an accurate reference meter to the transmitter at the CONNECT REFERENCE METER prompt
by shunting the power to the transmitter through the reference meter at some point in the loop.

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

Using AMS Device Manager

1. Right click on the device and select Service Tools.

2. In the left navigation pane click on Maintenance.

3. Find the Analog Calibration tab and click on the Analog Trim button.

4. Follow the screen prompts that will guide you through the Analog Trimming process.

Using the Local Operator Interface

Reference the below image for guidance on where to find Analog Trim in the LOI menu.

Reference Manual

00809-0100-4728, Rev MB

3, 4, 5, 1

Figure 5-5. Trimming the Analog Output with the LOI

5.5.3 Scaled output trim

The Scaled Output Trim matches the 4 and 20mA points to a user-selectable reference scale other than 4
and 20 mA (2–10 volts, for example). To perform a scaled D/A trim, connect an accurate reference meter
to the transmitter and trim the output signal to scale as outlined in the “Trim the analog output”
procedure.

Using Field Communicator

1. Connect an accurate reference meter to the transmitter at the CONNECT REFERENCE METER prompt
by shunting the power to the transmitter through the reference meter at some point in the loop.

From the HOME screen, enter the Fast Key sequence

66

Device Dashboard Fast Keys

3, 4, 5, 2

Operation and Maintenance

Reference Manual

Standard IEC 751
“Ideal” Curve

(1)

Actual Curve

Tem per atu re, °C

Resistance, Ohm

0 °C

1. The Actual Curve is identified from the Callendar-Van Dusen equation.

TotalSystemAccuracy TransmitterAccuracy

2

SensorAccuracy

2

+=

00809-0100-4728, Rev MB

Using AMS Device Manager

1. Right click on the device and select Service Tools.

2. In the left navigation pane click on Maintenance.

3. Find the Analog Calibration tab and click on the Scaled Trim button.

4. Follow the screen prompts that will guide you through the analog trimming process.

5.6 Transmitter-Sensor Matching

Use Transmitter-Sensor Matching to enhance the temperature measurement accuracy of the system and
if you have a sensor with Callendar-Van Dusen constants. When ordered from Emerson Process
Management, sensors with Callendar-Van Dusen constants are NIST-traceable.

The Rosemount 644 accepts Callendar-Van Dusen constants from a calibrated RTD schedule and
generates a special custom curve to match that specific sensor Resistance vs. Temperature performance.

Figure 5-6.

Figure 5-6. Standard vs. Actual Sensor Curve

Operation and Maintenance

July 2016

Matching the specific sensor curve with the transmitter significantly enhances the temperature
measurement accuracy. See the comparison below in Ta bl e 5 - 1.

Table 5-1. Standard RTD vs. RTD with Matched CVD Constants with Standard Transmitter Accuracy

System accuracy comparison at 150 °C using a PT 100 (=0.00385)

RTD with a span of 0 to 200 °C

Standard RTD Matched RTD

Rosemount 644H ±0.15 °C Rosemount 644H ±0.15 °C

Standard RTD ±1.05 °C Matched RTD ±0.18 °C

Tot al System

1. Calculated using root-summed-squared (RSS) statistical method

Operation and Maintenance

(1)

±1.06 °C Tota l Sy stem

(1)

±0.23 °C

67

Operation and Maintenance

TotalSystemAccuracy TransmitterAccuracy

2

SensorAccuracy

2

+=

July 2016

Table 5-2. Standard RTD vs. RTD with Matched CVD Constants with Enhanced Transmitter

Accuracy Option P8

System accuracy comparison at 150 °C using a PT 100 (=0.00385)

Standard RTD Matched RTD

Rosemount 644 ±0.10 °C Rosemount 644 ±0.10 °C

Standard RTD ±1.05 °C Matched RTD ±0.18 °C

Tot al System

1. Calculated using root-summed-squared (RSS) statistical method

Callendar-Van Dusen equation

The following input variables, included with specially-ordered Rosemount temperature sensors, are
required:

R0 = Resistance at Ice Point
Alpha = Sensor Specific Constant
Beta = Sensor Specific Constant
Delta = Sensor Specific Constant

(1)

R

= Ro + Roa [t – d(0.01t-1)(0.01t) – b(0.01t – 1)(0.01t)3]

t

RTD with a span of 0 to 200 °C

±1.05 °C Tota l Sy stem

(1)

Reference Manual

00809-0100-4728, Rev MB

±0.21 °C

To input Callendar-Van Dusen constants, perform one the following procedures:

Entering CVD constants using Field Communicator

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

2, 2, 1, 9

Entering CVD constants using AMS Device Manager

1. Right click on the device and select Configure.

2. In the left navigation pane choose Manual Setup and choose the Sensor 1 or Sensor 2 tab
depending on the need.

3. Find the Transmitter Sensor Matching (CVD) group box and enter in the required CVD constants. Or
click the Set CVD Coefficients button to be guided through steps. You may also click the Show CVD
Coefficients button to see the current coefficients loaded into the device.

4. Click Apply when complete.

Note

When the transmitter-senor matching is disabled, the transmitter reverts to either user or factory trim,
whichever was used previously. Make certain the transmitter engineering units default correctly before
placing the transmitter into service.

68

Operation and Maintenance

Reference Manual

CALIBRAT
DAMPING
VARIABLE MAP
TAG
ALM SAT VALUES
PASSWORD
SIMULATE

HART REV

HART REV

.....

BACK TO MENU
EXIT MENU

HART REV 7
HART REV 5
BACK TO MENU
MAIN MENU

VIEW CONFIG
ZERO TRIM
UNITS
RERANGE
LOOP TEST
DISPLAY

EXTENDED MENU

EXTENDED MENU

EXIT MENU

00809-0100-4728, Rev MB

5.7 Switching HART Revision

Some systems are not capable of communicating with HART Revision 7 devices. The following
procedures list how to change HART revisions between HART Revision 7 and HART Revision 5.

5.7.1 Using the Generic Menu

If the HART configuration tool is not capable of communicating with a HART Revision 7 device, it should
load a Generic Menu with limited capability. The following procedures allow for switching between HART
Revision 7 and HART Revision 5 from a Generic Menu in any HART compliant configuration tool.

1. Locate Message field.

a. To change to HART Revision 5, Enter: HART5 in the message field.
b. To change to HART Revision 7, Enter: HART7 in the message field.

5.7.2 Using Field Communicator

Follow steps within the Field Communicator to complete the HART revision change.

From the HOME screen, enter the Fast Key sequence

Device Dashboard Fast Keys

Operation and Maintenance

July 2016

2, 2, 8, 3

5.7.3 Using AMS Device Manager

1. Right click on the device and select Configure.

2. In the left navigation pane choose Manual Setup and click on the HART tab.

3. Click on the Change HART Revision button and follow the prompts.

Note

HART Revision 7 is only compatible with AMS Device Manager 10.5, and greater. AMS Device Manager
version 10.5 requires a software patch to be compatible.

5.7.4 Using Local Operator Interface

Reference the below image for where to find HART Rev in the LOI menu.

Figure 5-7. Trimming the Analog Output with the LOI

Operation and Maintenance

69

Operation and Maintenance

July 2016

Reference Manual

00809-0100-4728, Rev MB

70

Operation and Maintenance

Reference Manual

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Section 6 Troubleshooting

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 71

Safety messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 71

Troubleshooting the 4-20 mA/HART output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 72

Diagnostic messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 73

6.1 Overview

Table 6.3 on page 72 provides summarized maintenance and troubleshooting suggestions for the most

common operating problems.

If you suspect malfunction despite the absence of any diagnostic messages on the Field Communicator
display, follow the procedures described in Table 6.3 on page 72 to verify that transmitter hardware and
process connections are in good working order. Under each of four major symptoms, specific
suggestions are offered for solving problems. Always deal with the most likely and easiest-to-check
conditions first.

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July 2016

6.2 Safety messages

Procedures and instructions in this section may require special precautions to ensure the safety of the
personnel performing the operations. Information that raises potential safety issues is indicated by a

warning symbol ( ). Refer to the following safety messages before performing an operation preceded
by this symbol.

Explosions could result in death or serious injury.

Installation of this transmitter in an explosive environment must be in accordance with the
appropriate local, national, and international standards, codes, and practices. Review the
approvals section of the Rosemount
safe installation.

 Before connecting a Field Communicator in an explosive atmosphere, ensure the instruments in

the loop are installed in accordance with intrinsically safe or non-incendive field wiring practices.

 In an Explosion-Proof/Flameproof installation, do not remove the transmitter covers when power

is applied to the unit.

Process leaks may cause harm or result in death.

 Install and tighten process connectors before applying pressure.

Electrical shock can result in death or serious injury.

 Avoid contact with the leads and terminals. High voltage that may be present on leads can cause

electrical shock.

™

644 Reference Manual for any restrictions associated with a

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6.3 Troubleshooting the 4-20 mA/HART output

Reference Manual

Symptom or
issue

Tra n sm it te r
Does Not
Communicate
with Field
Communicator

High Output

Potential
source

Loop Wiring

Sensor Input
Failure or
Connection

Loop Wiring

Power
Supply

Electronics

Corrective action

• Check the revision level of the transmitter device descriptors (DDs) stored in your

communicator. The communicator should report Dev v4, DD v1 (improved), or
reference “Field Communicator” on page 3-2 for previous versions. Contact
Emerson

™

Process Management Customer Central for assistance.

• Check for a minimum of 250 ohms resistance between the power supply and Field

Communicator connection.

• Check for adequate voltage to the transmitter. If a Field Communicator is

connected and 250 ohms resistance is properly in the loop, then the transmitter
requires a minimum of 12.0 V at the terminals to operate (over entire 3.5 to 23.0
mA operating range), and 12.5 V minimum to communicate digitally.

• Check for intermittent shorts, open circuits, and multiple grounds.

• Connect a Field Communicator and enter the transmitter test mode to check for a

sensor failure.

• Check for a sensor open or short circuit.

• Check the process variable to see if it is out of range.

• Check for dirty or defective terminals, interconnecting pins, or receptacles

• Check the output voltage of the power supply at the transmitter terminals. It

should be 12.0 to 42.4 Vdc (over entire 3.75 to 23 mA operating range).

• Connect a Field Communicator and enter the transmitter status mode to isolate

module failure.

• Connect a Field Communicator and check the sensor limits to ensure calibration

adjustments are within the sensor range.

Erratic Output

Low or No
Output

Loop Wiring

Electronics

Sensor
Element

Loop Wiring

Electronics

• Check for adequate voltage to the transmitter. It should be 12.0 to 42.4 Vdc at the

transmitter terminals (over entire 3.75 to 23 mA operating range).

• Check for intermittent shorts, open circuits, and multiple grounds.

• Connect a Field Communicator and enter the Loop test mode to generate signals

of 4 mA, 20 mA, and user-selected values.

• Connect a Field Communicator and enter the transmitter test mode to isolate

module failure.

• Connect a Field Communicator and enter the Transmitter test mode to isolate a

sensor failure.

• Check the process variable to see if it is out of range.

• Check for adequate voltage to the transmitter. It should be 12.0 to 42.4 Vdc (over

entire 3.75 to 23 mA operating range).

• Check for shorts and multiple grounds.

• Check for proper polarity at the signal terminal.

• Check the loop impedance.

• Connect a Field Communicator and enter the Loop test mode.

• Check wire insulation to detect possible shorts to ground.

• Connect a Field Communicator and check the sensor limits to ensure calibration

adjustments are within the sensor range.

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6.4 Diagnostic messages

Listed in the below sections are detailed tables of the possible messages that will appear on either the
LOI/LCD display, a Field Communicator, or an AMS system. Use the tables below to diagnose particular
status messages (i.e. Failed, Maintenance, Advisory).

6.4.1 Diagnostic messages: Failed–Fix now

LCD
display

Alert name

Electronics
Failure

Sensor

(1)

Open

Sensor

(1)

Short

Terminal
Tem pe ra tu re
Failure

Invalid
Configuration

Field Device
Malfunction

1. Sensor 1 is used here as an example. If Dual Sensors are ordered, this alert can apply to either sensor.

screen

ALARM

DEVICE

ALARM

FAI L

ALARM

SNSR 1

ALARM

FAI L

ALARM

SNSR 1

ALARM

FAI L

ALARM

TERM

ALARM

FAI L

CONFG

SNSR 1

WAR N

ERROR

ALARM

DEVICE

ALARM

FAI L

.
.
.

.
.

.
.

.
.

.
.

.
.
.

LOI
screen

ALARM
DEVICE

ALARM

FAI L

ALARM

SNSR 1

ALARM

FAI L

ALARM

SNSR 1

ALARM

FAI L

ALARM

TERM

ALARM

FAI L

CONFG

SNSR 1

WAR N

ERROR

ALARM
DEVICE

ALARM

FAI L

Problem Recommended action

Essential electronics in the device
have failed. For example, the

.

transmitter may have experienced
an electronics failure while

.

attempting to store information.

.

If diagnostics indicate an
electronics failure.

This message indicates that the
transmitter has detected an open
sensor condition. The sensor may

.

be disconnected, connected

.

improperly, or malfunctioning.

This message indicates that the
transmitter has detected a
shorted sensor condition. The
sensor may be disconnected,

.

connected improperly, or

.

malfunctioning.

The Terminal Temperature is
outside the internal RTD’s
specified operating range.

.
.

The Sensor Configuration (type
and/or connection) does not
match the sensor output and is

.

invalid.

.

The device has malfunctioned or
needs immediate attention.

.
.
.

1. Restart the transmitter.

2. If condition persists, replace the transmitter. Contact
the nearest Emerson Process Management Field
Service Center if necessary.

1. Verify the sensor connection and wiring. Refer to the
wiring diagrams found on the transmitter label to
ensure proper wiring.

2. Verify the integrity of the sensor and sensor lead
wires. If the sensor is faulty, repair or replace the
sensor.

1. Verify the process temperature is within the specified
sensor's range. Use the Sensor Information button to
compare with the process temperature.

2. Verify the sensor is properly wired and connected to
the terminals.

3. Verify the integrity of the sensor and sensor lead
wires. If the sensor is faulty, repair or replace the
sensor.

1. Verify the ambient temperature is within the device
specified operating range using the Terminal
Temperature Information Button.

1. Verify sensor type and number of wires matched the
Sensor Configuration of the device.

2. Reset the device.

3. If error persists, download the transmitter
configuration.

4. If error still present, replace the transmitter.

1. Perform a processor reset.

2. View other alerts to see if the transmitter indicates a
specific problem.

3. If the condition persists, replace the device.

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6.4.2 Diagnostic messages: Warning

LCD
display

Alert name

Hot Backup™
Active

Sensor Drift
Alert

(1)

Active

Sensor
Degraded

Calibration
Error [none] [none]

Sensor Out
of Operating

(1)

Limits

Terminal
Tem pe ra tu re
Out of
Operating
Limits

1. Sensor 1 is used here as an example. If Dual Sensors are ordered, this alert can apply to either sensor.

screen

HOT BU

SNSR 1

HOT BU

FAI L

WAR N

DRIFT

WAR N

ALERT

(1)

WAR N

SNSR 1

DEGRA
SNSR 1

SAT

SNSR 1

XX.XXX

SAT

TERM

DEGRA

WAR N

°C

.
.

.
.

.
.

.
.

.
.

LOI
screen

HOT BU

SNSR 1

HOT BU

FAI L

WARN

DRIFT

WARN

ALERT

WARN

SNSR 1

DEGRA
SNSR 1

SAT

SNSR 1

XX.XXX

SAT

TERM

DEGRA

WARN

Problem Recommended action

Sensor 1 has failed (open or
shorted) and Sensor 2 is
now the primary process

.

variable output.

.

The difference between
Sensor 1 and 2 has gone
beyond the user-configured

.

Drift Alert Threshold.

.

The resistance of the
thermocouple loop has
exceeded the configured
threshold. This could be

.

caused by excess EMF.

.

The value entered for the
user trim point was not
acceptable.

Sensor # readings are
outside the sensor's
specified range.

.
.

°C

The Terminal Temperature
is outside the on-board RTD
specified operating range

.
.

1. Replace Sensor 1 at you earliest convenience.

2. Reset Hot Backup feature in the device software.

1. Verify sensor connections are valid on the transmitter.

2. If necessary, check calibration of each sensor.

3. Verify process conditions match sensor outputs.

4. If calibration fails, one of the sensors has failed. Replace it at
your earliest convenience.

1. Check terminal connections on the Rosemount 644
terminal screws for corrosion.

2. Check the thermocouple loop for any signs of corrosion in
terminal blocks, wire thinning, wire breaks, or faulty
connections.

3. Verify the integrity of the sensor itself. Harsh process
conditions may cause long-term sensor failures.

1. Re-trim the device, make sure the user entered calibration
points are close to the applied calibration temperature.

1. Verify the process temperature is within the specified
sensor's range. Use the Sensor Information button to
compare with the process temperature.

2. Verify the sensor is properly wired and connected to the
terminals.

3. Verify the integrity of the sensor and sensor lead wires. If
the sensor is faulty, repair or replace the sensor.

1. Verify the ambient temperature is within the device
specified operating range using the Terminal Temperature
Information Button.

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6.4.3 Other LCD display messages

LCD
display

Alert name

LCD is not
displaying
correctly or
at all

Analog
Output
Fixed

Simulation
Active

screen

Rosemount

HART 7

WAR N

LOOP

WAR N

FIXED

[none] [none]

Rosemount

644

.
.

LOI screen Problem Recommended action

The display may not be
functioning or it may be

644

HART 7

WAR N

LOOP

WAR N

FIXED

stuck on Home screen

The analog output is set to
a fixed value and is not
currently tracking the HART

.

Primary Variable.

.

The device is in simulation
mode and may not be
reporting actual
information.

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If the meter does not appear to function, make sure
the transmitter is configured for the meter option you
desire. The meter will not function if the LCD display
option is set to Not Used.

1. Verify it was intended for the transmitter to be
operating in "Fixed Current Mode."

2. Disable "Fixed Current Mode" in Service Tools to have
the analog output operate normally.

1. Verify simulation is no longer required.

2. Disable simulation mode in service tools.

3. Perform a device reset.

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Safety Instrumented Systems (SIS) Certification

July 2016

Section 7 Safety Instrumented Systems (SIS)

Certification

Safety Instrumented Systems (SIS) certification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 77

Rosemount 644 safety certified identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 77

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 78

Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 78

Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 78

Alarm and saturation levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 79

Rosemount 644 SIS operation and maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 80

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 81

7.1 Safety Instrumented Systems (SIS) certification

The Rosemount™ 644 Temperature Transmitter is a 2-wire, 4-20 mA smart device. For safety
instrumented systems usage it is assumed that the 4-20 mA output is used as the primary safety
variable. The transmitter can be equipped with or without the display. The Rosemount 644 Temperature
Transmitter is classified as a Type B device according to IEC61508, having a hardware fault tolerance of 0.

The Rosemount 644 HART
in Safety Instrumented Systems up to SIL 2 and redundant transmitter use in Safety Instrumented
Systems up to SIL 3.

®

Head Mount Transmitter is certified to IEC 61508 for single transmitter use

7.2 Rosemount 644 safety certified identification

All Rosemount 644 HART Head Mount Transmitters must be identified as safety certified before
installing into SIS systems.

To identify a safety certified Rosemount 644, make sure the device satisfies number 1 below and at least
one of the options in 2, 3, or 4.

1. Verify the transmitter was ordered with Output Option code “A”. This signifies that it is a
4-20mA/HART device.

a. For Example: MODEL 644HA………..

2. See a yellow tag affixed to the top of the transmitter face, a yellow tag affixed to the outside of the
enclosure if preassembled, or the option code QT in the transmitter model string.

3. Check the NAMUR Software Revision located on the adhesive transmitter tag.
"SW _._._".
If the device label software revision is 1.1.1 or higher, the device is safety certified.

NAMUR Software Revision Number

(1)

SW

1. NAMUR Software Revision: Located on the adhesive device tag.

Safety Instrumented Systems (SIS) Certification

1.1.x

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4. Identify a certified Rosemount 644 by its Device Revision (found using any HART-compliant
communicator).
For the Rosemount 644, certified device revisions are as follows:

– Device Revision 8.x (HART 5)
– Device Revision 9.x (HART 7)

7.3 Installation

No special installation is required in addition to the standard installation practices outlined in this
document. Always ensure a proper seal by installing the electronics housing cover(s) so that metal
contacts metal.

The loop should be designed so the terminal voltage does not drop below 12 Vdc when the transmitter
output is 24.5 mA.

Environmental limits are available in the Rosemount 644 Product Data Sheet (document number
00813-0100-4728).

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7.4 Commissioning

The Rosemount 644 Safety Certified Transmitter can be commissioned by a person with average
knowledge of Rosemount temperature transmitters and the configuration device being used. Refer to

“System readiness” on page 9 to confirm your system's HART Revision capability and to confirm the

installation of the correct device drivers (separate drivers required for HART 5 and HART 7).

To commission the Rosemount 644 Safety Certified Transmitter using a 375/475 Field Communicator,
use the Table C-1 on page 155.

For more information on the Field Communicator visit http://www2.emersonpro­cess.com/en-US/brands/fieldcommunicator/Pages/fieldcommunicators.aspx.

7.5 Configuration

Use any HART capable configuration tool or the optional Local Operator Interface to communicate with
and verify the initial configuration or any configuration changes made to the Rosemount 644 prior to
operating in Safety Mode. All configuration methods outlined in Section 3 are the same for the safety
certified Rosemount 644 temperature transmitter with any differences noted.

Software Lock must be used in order to prevent unwanted changes to the transmitter configuration.

Note

Transmitter output is not safety-rated during the following: Configuration changes, Multidrop operation,
Simulation, Active Calibrator mode, and loop tests. Alternative means should be used to ensure process
safety during transmitter configuration and maintenance activities.

7.5.1 Damping

User-adjustable damping affects the transmitter’s ability to respond to changes in the applied process.
The damping value + response time should not exceed the loop requirements.

If using a thermowell assembly, make sure to also take into account the added response time due to
thermowell material.

78

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Normal Operation

4 mA

20 mA

20.8 mA

high saturation

21.75

(2)

3.9 mA

low saturation

3.75 mA

(1)

Normal Operation

4 mA

20 mA

20.5 mA

high saturation

22.5

(2)

3.8 mA

low saturation

3.6 mA

(1)

Normal Operation

4 mA

20 mA

20.1 - 22.9 mA

high saturation

20.2 - 23.0

(2)

3.7 - 3.9 mA

low saturation

3.6 - 3.8 mA

(1)

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7.6 Alarm and saturation levels

The Rosemount 644 features software driven alarm diagnostics. The independent circuit is designed to
provide backup alarm output if the microprocessor software fails. The transmitter will go to a high or low
output current for internally detected failures. The connected PLC must monitor the transmitter current
for the high and low output current values beyond the normal range. The alarm directions (HI/LO) are
user-selectable using the failure mode hardware switch found on the top face of the device. If failure
occurs, the position of the switch determines the direction in which the output is driven (HI or LO). The
switch feeds into the digital-to-analog (D/A) converter, which drives the proper alarm output even if the
microprocessor fails. The values at which the transmitter drives its output in failure mode depends on
whether it is configured to Standard, Custom, or NAMUR-compliant (NAMUR recommendation NE 43,
June 1997) operation. Figure 7-1 on page 79 shows the alarm ranges available for the device to be
configured to. The DCS, or safety logic solver, should be configured to match transmitter configuration.

Setting the alarm values is a two-step process:

1. With a Field Communicator, select the alarm and saturation levels using the following Fast Key
sequence 1, 3, 4, 2.

2. Position the alarm switch to the required HI or LO position.

July 2016

Figure 7-1. Alarm Levels

Rosemount alarm level

NAMUR alarm level

Custom alarm level

1. Transmitter Failure, hardware or software alarm in LO position.

2. Transmitter Failure, hardware or software alarm in HI position.

3. High alarm must be at least 0.1 mA higher than the high saturation value.

4. Low alarm must be at least 0.1 mA lower than the low saturation value.

(3)(4)

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7.7 Rosemount 644 SIS operation and maintenance

7.7.1 Proof test

The following proof tests are recommended. In the event that an error is found in the safety
functionality, proof test results and corrective actions taken must be documented at www.EmersonPro­cess.com/Rosemount/Safety. Use Table C-1 on page 155 to perform looptest, review device variables,
and view status.

The required proof test intervals depends upon the transmitter configuration and the temperature
sensor(s) in use. Guidance is available in Table 7-1 on page 81. Refer to the Rosemount 644 FMEDA report
for further information.

7.7.2 Abbreviated proof test

Conducting the abbreviated proof test detects approximately 63 percent of transmitter DU failures, and
approximately 90 percent of temperature sensor(s) DU failures, not detected by the Rosemount 644
safety-certified automatic diagnostics, for a typical overall assembly coverage of 67 percent.

1. Bypass the safety PLC or take other appropriate action to avoid a false trip.

2. Using Loop Test, enter the milliampere value representing a high alarm state.

3. Check the reference meter to verify the mA output corresponds to the entered value. This tests for
compliance voltage problems such as a low loop power supply voltage or increased wiring resistance.
This also tests for other possible failures.

4. Using Loop Test, enter the milliampere value representing a low alarm state. This tests for possible
dormant current related failures.

5. Check the reference meter to verify the mA output corresponds to the entered value.

6. Use a Field Communicator to view detailed device status to ensure no alarms or warnings are present
in the transmitter.

7. Check that sensor value(s) are reasonable in comparison to a basic process control system (BPCS)
value.

8. Restore the loop to full operation. Remove the bypass from the safety PLC or otherwise restore
normal operation.

9. Document the test results per the plant’s requirements.

7.7.3 Extended proof test

Conducting the extended proof test, which includes the abbreviated proof test, detects approximately
96 percent of transmitter DU failures and approximately 99 percent of temperature sensor(s) DU failures,
not detected by the Rosemount 644 safety-certified automatic diagnostics, for a typical overall assembly
coverage of 96 percent.

80

1. Bypass the safety PLC or take other appropriate action to avoid a false trip.

2. Execute the abbreviated proof test.

3. Perform a minimum two point sensor verification check. If two sensors are used, repeat for each
sensor. If calibration is required for the installation, it may be done in conjunction with this
verification.

4. Verify the housing temperature value is reasonable.

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5. Restore the loop to full operation. Remove the bypass from the safety PLC or otherwise restore
normal operation.

6. Document the test results per the plant’s requirements.

Table 7-1. Proof Test Intervals

4-wire RTD 10 years 10 years

Thermocouple 1 year 10 years

Dual Thermocouple 10 years 10 years

Dual 3-wire RTD 10 years 10 years

Thermocouple and 3-wire RTD 10 years 10 years

Proof test intervals are based on sensor failure rates from the “Electrical and Mechanical Component
Reliability Handbook, Second Edition”, exida, 2008. A low stress environment is assumed, with 30 percent
of SIL 2 PFDavg limit budgeted for the transmitter and sensor element. See the FMEDA report for
additional details or references.

Safety Instrumented Systems (SIS) Certification

July 2016

Sensors Abbreviated proof test Extended proof test

2 years 2 years

Visual inspection

Not required

Special tools

Not required

Product repair

The Rosemount 644 is repairable by replacement only.

All failures detected by the transmitter diagnostics or by the proof-test must be reported. Feedback can
be submitted electronically at www.EmersonProcess.com/Rosemount/Safety/Safety-Cert-Temp.htm
(Contact Us button).

7.8 Specifications

The Rosemount 644 must be operated in accordance to the functional and performance specifications
provided in the Rosemount 3051 Product Data Sheet (document number 00813-0100-4728).

7.8.1 Failure rate data

The FMEDA report includes failure rates and common cause Beta factor estimates.

The report is available at www.EmersonProcess.com/Rosemount/Safety-Products.

7.8.2 Failure values

Safety accuracy: ±2.0 percent
Transmitter response time: 1.5 second
Self-diagnostics Test: At least once every 60 minutes

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7.8.3 Product life

50 years - based on worst case component wear-out mechanisms - not based on wear-out of process
sensors.

Report any safety related product information at: http://rosemount.d1asia.ph/rosemount/safety/Repor­tAFailure_newweb.asp

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Appendix A Specifications and Reference Data

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 83

4–20 mA / HART specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 85

Dimensional drawings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 88

Ordering information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 91

Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 96

Specifications and Reference Data for Rosemount 644 HART Head Mount . . . . . . . . . . . . . . . page 97

A.1 Specifications

A.1.1 Functional

Inputs

User-selectable; sensor terminals rated to 42.4 Vdc. See“Accuracy”

on page 86 for sensor options.

Output

Single 2-wire device with 4-20 mA/HART® (Revision 5 or 7
Selectable), linear with temperature or input.

Isolation

Input/output isolation tested to 620 Vrms (876.8 Vpp) at 50/60 Hz

Local display

The optional five-digit integral LCD display includes a floating or
fixed decimal point. It can also display engineering units (°F, °C, °R,
K, , and millivolts), mA, and percent of span. The display can be
configured to alternate between selected display options. Display
settings are preconfigured at the factory according to the standard
transmitter configuration. They can be reconfigured in the field
using HART communications.

The device also supports the use of a two-line, 8- and 6-digit
(respectively) Local Operator Interface display supporting the
same functionality as the basic display with the added capability to
perform a number of configuration tasks on the Rosemount 644.

Humidity limits

0–95% relative humidity

Update time

 0.5 seconds per sensor

1 sec - Head mount HART ordered with Dual Sensors)

A.1.2 Physical

Electrical connections

Model Power and sensor terminals

Rosemount™
644H

Rosemount
644R

Field Communicator connections

Communication terminals

Rosemount 644H Clips permanently fixed to terminal block

Rosemount 644R Clips permanently fixed to front panel

Materials of construction

Electronics housing and terminal block

Rosemount
644H

Rosemount
644R

Enclosure (Options J5, J6, R1, and R2)

Housing Low-copper aluminum

Paint Polyurethane

Cover O-ring Buna-N

Materials of constructions (stainless steel housing for
Biotechnology, Pharmaceutical Industries, and Sanitary
Applications)

Housing and Standard Meter Cover

 316 SST

Cover O-Ring

 Buna-N

Compression screws permanently fixed to
terminal block

Compression screw permanently fixed to front
panel

GE polyphenylene oxide glass reinforced

Polycarbonate

Accuracy

HART protocol (0-100 °C): ±0.18 °C

±0.1 °C (when ordered with option P8)

Specifications and Reference Data

(default configuration) PT 100

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Specifications and Reference Data

July 2016

Mounting

The Rosemount 644R attaches directly to a wall or a DIN rail. The
Rosemount 644H installs in a connection head or universal head
mounted directly on a sensor assembly, apart from a sensor
assembly using a universal head, or to a DIN rail using an optional
mounting clip.

Weight

Code Options Weight

644 HART, Head Mount Transmitter 96 g (3.39 oz)

644R HART, Rail Mount Transmitter 174 g (6.14 oz)

M5 LCD Display 38 g (1.34 oz)

J5, J6 Universal Head, Standard Cover 577 g (20.35 oz)

J5, J6 Universal Head, Meter Cover 667 g (23.53 oz)

J7, J8 SST Universal Head, Std. Cover 1620 g (57.14 oz)

J7, J8 SST Universal Head, Meter Cover 1730 g (61.02 oz)

R1, R2

R1, R2

R3, R4

R3, R4

Weight (stainless steel housing for Biotechnology,
Pharmaceutical Industries, and Sanitary Applications)

Aluminum Connection Head, Std.
Cover

Aluminum Connection Head, Meter
Cover

Cast SST Connection Head, Std
Cover

Cast SST Connection Head, Meter
Cover

523 g (18.45 oz)

618 g (21.79 oz)

1615 g (56.97 oz)

1747 g (61.62 oz)

Code Standard cover Meter cover

S1 840 g (27 oz) 995 g (32 oz)

S2 840 g (27 oz) 995 g (32 oz)

S3 840 g (27 oz) 995 g (32 oz)

S4 840 g (27 oz) 995 g (32 oz)

Enclosure ratings (Rosemount 644H)

All available enclosures are Type 4X, IP66, and IP68.

Sanitary housing surface

Surface finish is polished to 32 RMA. Laser etched product marking
on housing and standard covers.

A.1.3 Performance

EMC (ElectroMagnetic Compatibility)

NAMUR NE 21 Standard

The Rosemount 644 meets the requirements for the NAMUR NE 21
rating.

Susceptibility Parameter

ESD

Radiated

Burst

Surge

Conducted

CE Electromagnetic compatibility compliance testing

The Rosemount 644 is compliant with Directive 2004/108/EC.
Meets the criteria under IEC 61326:2006.

Power supply effect

Less than ±0.005% of span per volt

Stability

RTDs and thermocouples have a stability of ±0.15% of output
reading or 0.15 °C (whichever is greater) for 24 months.

When ordered with the P8 option code:

 RTDs: ±0.25% of reading or 0.25 °C, whichever is greater, for 5

years

 Thermocouples: ±0.5% of reading or 0.5 °C, whichever is greater,

for 5 years

Self calibration

The analog-to-digital measurement circuitry automatically
self-calibrates for each temperature update by comparing the
dynamic measurement to extremely stable and accurate internal
reference elements.

Vibration effect

The Rosemount 644 HART is tested to the following specifications
with no effect on performance per IEC 60770-1, 2010:

• 6 kV contact discharge

• 8 kV air discharge

• 80 MHz to 2.7 GHz at 10 V/m

• 1 kV for I.O.

• 1 kV line–ground

• 10 kHz to 80 MHz at 10 V

Influence

HART

None

< 1.0%

None

None

< 1.0%

84

Frequency Vibration

10 to 60 Hz 0.35 mm displacement

60 to 1000 Hz 5 g (50 m/s2) peak acceleration

Specifications and Reference Data

Specifications and Reference Data

2-wire

RTD and V

3-wire RTD

and V

4-wire RTD

and V

T/C

and mV

*

1234

12 34

1234

1234







Lower
Specification
Limit

Upper

Specification

Limit

–3 –2 –1 1 2 3

4–20 mA dc

1322
1100

1000

750

500

250

0

10 12.0 20 30 40 42.4

Supply Voltage (Vdc)

Operating Region

July 2016

Reference Manual

00809-0100-4728, Rev MB

Sensor connections

Rosemount 644 Sensor Connection Diagram:

Rosemount 644 Head mount

Rosemount 644 Sensor Connection Diagram:

Rosemount 644 Rail mount

Conversely, a vendor who “grades” product without using process
control, or who is not committed to ± 3 performance, will ship a
higher percentage of units that are barely within advertised
specification limits.

Figure A-1. Typical Accuracy

Accuracy distribution shown is for the Rosemount 644, Pt 100 RTD sensor,
Range 0 to 100 °C

A.2 4–20 mA / HART specifications

A.2.1 Communication requirements

Transmitter power terminals are rated to 42.4 Vdc. A Field
Communicator requires a loop resistance between 250 –
1100 ohms. The Rosemount 644 HART device does not
communicate when power is below 12 Vdc at the transmitter
terminals.

* Emerson™ Process Management provides 4-wire sensors for all single

element RTDs. You can us e these RTDs in 3-wi re configurations by leavin g
the unneeded leads disconnected and insulated with electrical tape.

A.1.4 Conformance to specifications

A Rosemount product not only meets its published specifications,
but most likely exceeds them. Advanced manufacturing
techniques and the use of Statistical Process Control provide

(1)

specification conformance to at least ± 3 s
to continual improvement ensures that product design, reliability,
and performance will improve annually.

For example, the Reference Accuracy distribution for the
Rosemount 644 is shown in Figure A-1. Our specification limits are
± 0.15 °C, but, as the shaded area shows, approximately 68 percent
of the units perform three times better than the limits. Therefore,
it is very likely that you will receive a device that performs much
better than our published specifications.

. Our commitment

A.2.2 Power supply

An external power supply is required for HART devices. The
transmitter operates on 12.0 to 42.4Vdc transmitter terminal
voltage with load resistance between 250 and 660 ohms. A
minimum of 17.75 Vdc power supply is required with a load of 250
ohms. Transmitter power terminals are rated to 42.4 Vdc.

Maximum Load = 40.8 x (Supply Voltage – 12.0)

1. Sigma ( ) is a statistical symbol to designate the standard deviation from
the mean value of a normal distribution.

Specifications and Reference Data

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Specifications and Reference Data

July 2016

A.2.3 Temperature limits

Operating limit Storage limit

With LCD Display

Without LCD Display

–4 to 185 °F
–20 to 85 °C

–40 to 185 °F
–40 to 85 °C

–50 to 185 °F
–45 to 85 °C

–58 to 248 °F
–50 to 120 °C

A.2.4 Hardware and software failure mode

The Rosemount 644 features software driven alarm diagnostics.
The independent circuit is designed to provide backup alarm
output if the microprocessor software fails. The alarm directions
(HIGH/LO) are user-selectable using the failure mode switch. If
failure occurs, the position of the switch determines the direction
in which the output is driven (HI or LO). The switch feeds into the
digital-to-analog (D/A) converter, which drives the proper alarm
output even if the microprocessor fails. The values at which the
transmitter drives its output in failure mode depends on whether it
is configured to standard, custom, or NAMUR-compliant (NAMUR
recommendation NE 43, June 1997) operation. Tab l e A - 1 shows
the alarm ranges available for the device to be configured to.

Table A-1. Available Alarm Range

Standard

Linear Output: 3.9  I

Fail High: 21  I  23 21  I  23

Fail Low: 3.5  I  3.75 3.5  I  3.6

1. Measured in milliamperes.

2. I = Process Variable (current output).

(2)

 20.5

(1)

NAMUR- NE 43
Compliant

3.8  I  20.5

A.2.5 Custom alarm and saturation level

Custom factory configuration of alarm and saturation level is
available with option code C1 for valid values. These values can
also be configured in the field using a Field Communicator.

A.2.6 Turn-on time

Performance within specifications in less than 5.0 seconds after
power is applied, when damping value is set to 0 seconds.

A.2.7 Transient protection

The Rosemount 470 prevents damage from transients induced by
lightning, welding, or heavy electrical equipment. For more
information, refer to the Rosemount 470 Product Data Sheet
(document number 00813-0100-4191).

A.2.8 Accuracy

Table A-2. Rosemount 644 Input Options and Accuracy

Sensor

options

2-, 3-, 4-wire RTDs °C °F °C °F °C °F
Pt 100 ( = 0.00385) IEC 751 –200 to 850 –328 to 1562 10 18 ± 0.15 ± 0.27 ±0.03% of span
Pt 200 ( = 0.00385) IEC 751 –200 to 850 –328 to 1562 10 18 ± 0.15 ± 0.27 ±0.03% of span
Pt 500 ( = 0.00385) IEC 751 –200 to 850 –328 to 1562 10 18 ± 0.19 ± 0.34 ±0.03% of span
Pt 1000 ( = 0.00385) IEC 751 –200 to 300 –328 to 572 10 18 ± 0.19 ± 0.34 ±0.03% of span
Pt 100 ( = 0.003916) JIS 1604 –200 to 645 –328 to 1193 10 18 ± 0.15 ± 0.27 ±0.03% of span
Pt 200 ( = 0.003916) JIS 1604 –200 to 645 –328 to 1193 10 18 ± 0.27 ± 0.49 ±0.03% of span
Ni 120 Edison Curve No. 7 –70 to 300 –94 to 572 10 18 ± 0.15 ± 0.27 ±0.03% of span

Cu 10

Pt 50 ( = 0.00391) GOST 6651-94 –200 to 550 –328 to 1022 10 18 ± 0.30 ± 0.54 ±0.03% of span
Pt 100 ( = 0.00391) GOST 6651-94 –200 to 550 –328 to 1022 10 18 ± 0.15 ± 0.27 ±0.03% of span
Cu 50 ( = 0.00426) GOST 6651-94 –50 to 200 –58 to 392 10 18 ±1.34 ± 2.41 ±0.03% of span
Cu 50 ( = 0.00428) GOST 6651-94 –185 to 200 –301 to 392 10 18 ±1.34 ± 2.41 ±0.03% of span
Cu 100 ( = 0.00426) GOST 6651-94 –50 to 200 –58 to 392 10 18 ±0.67 ± 1.20 ±0.03% of span
Cu 100 ( = 0.00428) GOST 6651-94 –185 to 200 –301 to 392 10 18 ±0.67 ± 1.20 ±0.03% of span

Thermocouples

(5)

Typ e B

Typ e E

(4)

Sensor

reference

Edison Copper

Winding No. 15

NIST Monograph

175, IEC 584

NIST Monograph

175, IEC 584

Input

ranges

–50 to 250 –58 to 482 10 18 ±1.40 ± 2.52 ±0.03% of span

100 to 1820 212 to 3308 25 45 ± 0.77 ± 1.39 ±0.03% of span

–50 to 1000 –58 to 1832 25 45 ± 0.20 ± 0.36 ±0.03% of span

Recommended

Min. Span

(1)

Digital

accuracy

(2)

D/A

accuracy

(3)

86

Specifications and Reference Data

Specifications and Reference Data

July 2016

Reference Manual

00809-0100-4728, Rev MB

Table A-2. Rosemount 644 Input Options and Accuracy

Sensor

options

Type J

(6)

Type K

Type N

Type R

Type S

Type T

DIN Type L DIN 43710 –200 to 900 –328 to 1652 25 45 ± 0.35 ± 0.63 ±0.03% of span
DIN Type U DIN 43710 –200 to 900 –328 to 1112 25 45 ± 0.35 ± 0.63 ±0.03% of span
Type W5Re/W26Re ASTM E 988-96 0 to 2000 32 to 3632 25 45 ± 0.70 ± 1.26 ±0.03% of span

GOST Type L

Sensor

reference

NIST Monograph

175, IEC 584

NIST Monograph

175, IEC 584

NIST Monograph

175, IEC 584

NIST Monograph

175, IEC 584

NIST Monograph

175, IEC 584

NIST Monograph

175, IEC 584

GOST R

8.585-2001

Input

ranges

Recommended

Min. Span

(1)

Digital

accuracy

(2)

D/A

accuracy

–180 to 760 –292 to 1400 25 45 ± 0.35 ± 0.63 ±0.03% of span

–180 to 1372 –292 to 2501 25 45 ± 0.50 ± 0.90 ±0.03% of span

–200 to 1300 –328 to 2372 25 45 ± 0.50 ± 0.90 ±0.03% of span

0 to 1768 32 to 3214 25 45 ± 0.75 ± 1.35 ±0.03% of span

0 to 1768 32 to 3214 25 45 ± 0.70 ± 1.26 ±0.03% of span

–200 to 400 –328 to 752 25 45 ± 0.35 ± 0.63 ±0.03% of span

–200 to 800 –328 to 1472 25 45 ± 1.00 ± 1.26 ±0.03% of span

Other input types

Millivolt Input –10 to 100 mV ±0.015 mV ±0.03% of span
2-, 3-, 4-wire Ohm Input 0 to 2000 ohms ±0.45 ohm ±0.03% of span

1. No minimum or maximum span restrictions within the input ranges. Recommended minimum span will hold noise within accuracy specification with damping at zero
seconds.

2. The published digital accuracy applies over the entire sensor input range. Digital output can be accessed by HART or F
Rosemount control system.

3. Total analog accuracy is the sum of digital and D/A accuracies. This is not applicable for F

4. Total digital accuracy for thermocouple measurement: sum of digital accuracy +0.5 °C. (cold junction accuracy).

5. Digital accuracy for NIST Type B T/C is ±3.0 °C (±5.4 °F) from 100 to 300 °C (212 to 572 °F).

6. Digital accuracy for NIST Type K T/C is ±0.70 °C (±1.26 °F) from –180 to –90 °C (–292 to –130 °F).

OUNDATION Fieldbus.

OUNDATION

™

Fieldbus Communications or

(3)

Accuracy example

When using a Pt 100 ( = 0.00385) sensor input with a 0 to 100 °C
span:

 Digital accuracy = ±0.15 °C

 D/A accuracy = ±0.03% of 100 °C or ±0.03 °C

 Total accuracy = ±0.18 °C.

Specifications and Reference Data

87

Reference Manual

31 (1.2)

Rosemount 644 Transmitter

LCD Rotation Screws

LCD Display

36

(1.4)

104

(4.1)

82

(3.2)

Sensor
Ter mi na l s

Power
Ter mi na l s

00809-0100-4728, Rev MB

A.3 Dimensional drawings

Figure A-2. Rosemount 644 (DIN A Head Mount)

HART device shown with captivated screw terminals

60 (2.4)

Sensor Terminals

Display
Connection

33 (1.3)

Communication
Terminals

59 (2.3)

24 (.96)

Specifications and Reference Data

July 2016

Failure
Mode Switch

Power Terminals

Dimensions are in millimeters (inches)

Figure A-3. Rosemount 644 with LCD Display

Figure A-4. Rosemount 644 Rail Mount

88

Specifications and Reference Data

Specifications and Reference Data

G-Rail

Grooves

Top Hat Rail

Grooves

Screw Holes
for Mounting
to a Wall

Tra n sm it te r

Mounting
Hardware

Rail Clip

Tra ns mi tt er

Mounting
Hardware

Rail Clip

95 (3.74)

96 (3.76)

112 (4.41)

Meter Cover

316 SST “U” Bolt
Mounting, 2-inch
Pipe

75

(2.93)

Label

Standa rd

Cover

LCD

Display

103 (4.03) with LCD
Display

78 (3.07)

128 (5.04) with
LCD Display

100

(3.93)

104

(4.09)

July 2016

Figure A-5. Mounting Kits for Rosemount 644 Head Mount

Reference Manual

00809-0100-4728, Rev MB

Rosemount 644R rail and wall clips

(part number 03044-4103-0001)

A.3.1 LCD display cover

 316L SST

 Glass

Figure A-6. Threaded-Sensor Universal Head (Option

code J5, J6, J7 or J8)

Rosemount 644H rail clips

G-Rail (asymmetric) Top hat rail (symmetric)

Note: Kit (part number 00644-5301-0010) includes

mounting hardware and both types of rail kits.

Figure A-7. DIN Style Sensor Connection Head (Option

code R1, R2, R3 or R4)

Note: A “U” Bolt is shipped with each universal head unless assembly
option XA is ordered.

Specifications and Reference Data

Dimensions are in millimeters (inches).

89

Reference Manual

79.8 (3.14)

70.0 (2.76)

33 (1.3)

76.2 (3.0)

24.4

(0.96)

25.4 (1.0)

44.5 (1.75)

27.9 (1.1)

Standard Cover

Housing

O-Ring

70.0 (2.76)

33 (1.3)

76.2 (3.0)

47 (1.85)

61 (2.4)

25.4 (1.0)

44.5 (1.75)

27.9 (1.1)

74.4 (2.93)

LCD Display Cover

Housing

O-Ring

00809-0100-4728, Rev MB

Specifications and Reference Data

July 2016

A.3.2 Stainless steel housing for biotechnology, pharmaceutical industries, and sanitary applications

Figure A-8. Sanitary Housing (Option Codes S1, S2, S3, S4)

Standard cover LCD display cover

Dimensions are in millimeters (inches).

90

Specifications and Reference Data