Emerson 848T User Manual

Reference Manual

00809-0100-4697, Rev EA

October 2011

Rosemount 848T High Density Temperature Transmitter with FOUNDATION™ fieldbus

Device Revision 7

www.rosemount.com

Reference Manual

00809-0100-4697, Rev EA

October 2011

Rosemount 848T

Rosemount 848T High Density

Temperature Transmitter with

FOUNDATION fieldbus

NOTICE

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-[phone]

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 Process Management Sales Representative.

www.rosemount.com

Reference Manual

00809-0100-4697, Rev EA

October 2011

Rosemount 848T

Table of Contents

SECTION 1

Introduction

SECTION 2

Installation

SECTION 3

Configuration

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

Service Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

Mounting to a DIN Rail Without an Enclosure . . . . . . . . . . . . . . . . 2-2

Mounting to a Panel with a Junction Box . . . . . . . . . . . . . . . . . . . . 2-2

Mounting to a 2-in. Pipe Stand . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

Wiring. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4

Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4

Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7

Surges/Transients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7

Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8

Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10

Tagging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12

Using Cable Glands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12

Using Conduit Entries. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1 Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2 Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2 Transmitter Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2 Custom Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2 Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2 Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3 Damping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3 Configure the Differential Sensors . . . . . . . . . . . . . . . . . . . . . . . . . 3-3 Configure Measurement Validation . . . . . . . . . . . . . . . . . . . . . . . . 3-3 Common Configurations for High Density Applications . . . . . . . . . . . . 3-4 Interfacing Analog Transmitters to Foundation fieldbus . . . . . . . . . 3-6 Block Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7

Resource Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7 PlantWeb™ Alerts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-11

Recommended Actions for PlantWeb Alerts . . . . . . . . . . . . . . . . 3-14 Transducer Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15 Transducer Block Sub-Parameter Tables . . . . . . . . . . . . . . . . . . 3-20

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SECTION 4

Operation and

Maintenance

APPENDIX A

Reference Data

APPENDIX B

Product Certificates

APPENDIX C Foundation™ fieldbus Technology

APPENDIX D

Function Blocks

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1 Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1 Foundation fieldbus Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1 Commissioning (Addressing) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2 Hardware Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3 Sensor Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3 Communication/Power Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3 Resetting the Configuration (RESTART) . . . . . . . . . . . . . . . . . . . . 4-3 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4 Foundation fieldbus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4 Resource Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4 Transducer Block Troubleshooting. . . . . . . . . . . . . . . . . . . . . . . . . 4-4

Functional Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1

Physical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-3

Function Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-4

Performance Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-4

Dimensional Drawings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-8

Mounting Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-11

Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-12

Hazardous Locations Certificates . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1

North American Approvals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1

European Approvals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-4

Intrinsically Safe and Non-Incendive Installations . . . . . . . . . . . . . . . B-11

Installation Drawings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-12

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-1

Function Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-1

Device Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-3

Block Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-3

InstrumentSpecific Function Blocks . . . . . . . . . . . . . . . . . . . . . . .C-3

Alerts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-3

Network Communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-4

Link Active Scheduler (LAS). . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-4

Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-6

Scheduled Transfers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-6

Unscheduled Transfers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-7

Function Block Scheduling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-8

Analog Input (AI) Function Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-1

Functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-3

AI Block Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-8

Multiple Analog Input (MAI) Function Block. . . . . . . . . . . . . . . . . . . . .D-9

Functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-10

MAI Block Troubleshooting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-14

Input Selector Function Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-15

Functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-17

ISEL Block Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-20

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Rosemount 848T

Section 1

Introduction

SAFETY MESSAGES

Warnings

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 1-1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 1-2 Service Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 1-3

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 (). Please 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.

Process leaks could result in death or serious injury.

•Do not remove the thermowell while in operation. Removing while in operation may cause process fluid leaks.

•Install and tighten thermowells and sensors before applying pressure, or process leakage may result.

Electrical shock could cause death or serious injury.

•If the sensor is installed in a high voltage environment and a fault condition or installation error occurs, high voltage may be present on transmitter leads and terminals.

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

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Rosemount 848T

Reference Manual

00809-0100-4697, Rev EA

October 2011

OVERVIEW

Transmitter	The Rosemount 848T is optimal for process temperature measurement
	because of its ability to simultaneously measure eight separate and
	independent temperature points with one transmitter. Multiple temperature
	sensor types may be connected to each 848T transmitter. In addition, the
	848T can accept 4-20 mA inputs. The enhanced measurement capability of
	the 848T allows it to communicate these variables to any FOUNDATION
	fieldbus host or configuration tool.
Manual	This manual is designed to assist in the installation, operation, and
	maintenance of the Rosemount 848T Temperature Transmitter.

Section 1: Introduction

•Overview

•Considerations

•Return of Materials

Section 2: Installation

•Mounting

•Installation

•Wiring

•Power Supply

•Commissioning

Section 3: Configuration

•FOUNDATION fieldbus Technology

•Configuration

•Function Block Configuration

Section 4: Operation and Maintenance

•Hardware Maintenance

•Troubleshooting

Appendix A: Specification and Reference Data

•Specifications

•Dimensional Drawings

•Ordering Information

Appendix B: Product Certificates

•Hazardous Locations Certificates

•Intrinsically Safe and Non-Incendive Installations

•Installation Drawings

Appendix C: Foundation™ Fieldbus Technology

•Device Descriptions

•Block Operation

Appendix D: Function Blocks

•Analog Input (AI) Function Block

•Multiple Analog Input (MAI) Function Block

•Input Selector Function Block

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SERVICE SUPPORT

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 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

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, please contact an Emerson Process Management sales representative.

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.

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Section 2

Installation

SAFETY MESSAGES

Warnings

MOUNTING

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-1 Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-1 Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-4 Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-8 Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-10 Tagging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-11 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-12

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 (). Please 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.

Process leaks could result in death or serious injury.

•Do not remove the thermowell while in operation. Removing while in operation may cause process fluid leaks.

•Install and tighten thermowells and sensors before applying pressure, or process leakage may result.

Electrical shock could cause death or serious injury.

•If the sensor is installed in a high voltage environment and a fault condition or installation error occurs, high voltage may be present on transmitter leads and terminals.

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

The 848T is always mounted remote from the sensor assembly. There are three mounting configurations:

•To a DIN rail without an enclosure

•To a panel with an enclosure

•To a 2-in pipe stand with an enclosure using a pipe mounting kit

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Rosemount 848T

Reference Manual

00809-0100-4697, Rev EA

October 2011

Mounting to a DIN Rail Without an Enclosure

Figure 2-1. Mounting the 848T to a DIN Rail

To mount the 848T to a DIN rail without an enclosure, follow these steps:

1.Pull up the DIN rail mounting clip located on the top back side of the transmitter.

2.Hinge the DIN rail into the slots on the bottom of the transmitter.

3.Tilt the 848T and place onto the DIN rail. Release the mounting clip. The transmitter should be securely fastened to the DIN rail.

848T without installed

enclosure

DIN Rail

DIN Rail Mounting Clip

Mounting to a Panel with a Junction Box

Figure 2-2. Mounting the 848T junction box to a panel

When inside of a plastic or aluminum junction box, the 848T mounts to a panel using four 1/4-20 x 1.25-in. screws.

When inside of a stainless steel junction box, the 848T mounts to a panel using two 1/4-20 x 1/2-in. screws.

Aluminum/Plastic	Stainless Steel
848T with aluminum or plastic box
Cover
Screws (4)	848T with a stainless steel box
	Mounting
Mounting	Screws (2)
Screws (4)
Panel	Panel

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Mounting to a 2-in. Pipe Stand

Use the optional mounting bracket (option code B6) to mount the 848T to a 2-in. pipe stand when using a junction box.

Aluminum/Plastic Junction Box

Stainless Steel Junction Box

(styles JA and JP)

(style JS)

Front View

Side View

Front View

Side View

5.1	10.2	6.6 (167)	4.7
	(260)	fully	(119)	7.5 (190)
(130)		assembled
				fully
				assembled

Dimensions are in inches (millimeters)

Aluminum/Plastic Junction Box	Stainless Steel Junction Box
Mounted on a Vertical Pipe	Mounted on a Vertical Pipe

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WIRING

Figure 2-3. 848T Transmitter

Field Wiring

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.

NOTE

Do not apply high voltage (e.g. AC line voltage) to the transmitter terminals. Abnormally high voltage can damage the unit (bus terminals are rated to 42.4 VDC).

		6234 ft (1900 m) max
		(depending upon cable
	Integrated Power	characteristics)
	Conditioner	Terminators
	and Filter
		(Trunk)
	Power
	Supply	(Spur)	(Spur)
	FOUNDATION			Signal
	fieldbus Host or			Wiring
	configuration tool
		Devices 1 through 16*

	* Intrinsically safe installations may allow fewer devices per I.S. barrier
Connections	The 848T transmitter is compatible with 2 or 3-wire RTD, thermocouple, Ohm,
	and millivolt sensor types. Figure 2-4 shows the correct input connections to
	the sensor terminals on the transmitter. The 848T can also accept inputs from
	analog devices using the optional analog input connector. Figure 2-5 shows
	the correct input connections to the analog input connector when installed on
	the transmitter. Tighten the terminal screws to ensure proper connection.
Figure 2-4. Sensor Wiring
Diagram
	1 2	3	1	2	3	1	2	3	1	2	3
	2-wire		3-wire			Thermocouples /			2-Wire RTD
	RTD and		RTD and			Ohms and				with
	Ohms		Ohms*			Millivolts			Compensation
									Loop**

*Emerson Process Management provides 4-wire sensors for all single-element RTDs. Use these RTDs in 3-wire configurations by clipping the fourth lead or leaving it disconnected and insulated with electrical tape.

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

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RTD or Ohm Inputs

Various RTD configurations, including 2-wire and 3-wire are used in industrial applications. If the transmitter is mounted remotely from a 3-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). If using a 2-wire RTD, both RTD leads are in series with the sensor element, so errors can occur if the lead lengths exceed one foot of 20 AWG wire. Compensation for this error is provided when using 3-wire RTDs.

Thermocouple or Millivolt Inputs

Use appropriate thermocouple extension wire to connect the thermocouple to the transmitter. Make connections for millivolt inputs using copper wire. Use shielding for long runs of wire.

Analog Inputs

The analog connector converts the 4–20 mA signal to a 20–100 mV signal that can be read by the 848T and transmitted using FOUNDATION fieldbus.

Use the following steps when installing the 848T with the analog connector:

1.The 848T, when ordered with option code S002, comes with four analog connectors. Replace the standard connector with the analog connector on the desired channels.

2.Wire one or two analog transmitters to the analog connector according to Figure 2-5. There is space available on the analog connector label for identification of the analog inputs.

NOTE

Power supply should be rated to support the connected transmitter(s).

3.If the analog transmitters can communicate using HART protocol, the analog connectors are supplied with the ability to switch in a 250 ohm resistor for HART communication (see Figure 2-6).

One switch is supplied for each input (top switch for “A” inputs and bottom switch for “B” inputs). Setting the switch in the “ON” position (to the right) bypasses the 250 ohm resistor. Terminals are provided for each analog input to connect a Field Communicator for local configuration.

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Figure 2-5. 848T Analog Input

Wiring Diagram

Figure 2-6. 848T Analog

Connector

Analog Input

Connectors

Analog Transmitters

Power Supply

250 ohm resistor in the loop when switched to the left

HART	HART
Channel A	Channel B

Space available for identification of inputs

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Power Supply

Connections

The transmitter requires between 9 and 32 VDC to operate and provide

complete functionality. The DC power supply should provide power with less

than 2% ripple. A fieldbus segment requires a power conditioner to isolate the

power supply filter and decouple the segment from other segments attached

to the same power supply.

All power to the transmitter is supplied over the signal wiring. Signal wiring

should be shielded, twisted pair for best results in electrically noisy

environments. Do not use unshielded signal wiring in open trays with power

wiring or near heavy electrical equipment.

Use ordinary copper wire of sufficient size to ensure that the voltage across the

transmitter power terminals does not go below 9 VDC. The power terminals are

polarity insensitive. To power the transmitter:

1.

Connect the power leads to the terminals marked “Bus,” as shown in

Figure 2-7.

2.

Tighten the terminal screws to ensure adequate contact. No

additional power wiring is necessary.

Figure 2-7. Transmitter Label

NOT USED

SECURITY

SIMULATE ENABLE

	Ground
	(required with T1 option)
	Connect Power Leads Here
Surges/Transients	The transmitter will withstand electrical transients encountered through static
	discharges or induced switching transients. However, a transient protection
	option (option code T1) is available to protect the 848T against high-energy
	transients. The device must be properly grounded using the ground terminal
	(see Figure 2-7).

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GROUNDING	The 848T transmitter provides input/output isolation up to 620 V rms.
	NOTE
	Neither conductor of the fieldbus segment can be grounded. Grounding out
	one of the signal wires will shut down the entire fieldbus segment.
	Shielded Wire
	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 (most common).
	Ungrounded Thermocouple, mV, and RTD/Ohm Inputs
	Option 1:
	1.	Connect signal wiring shield to the sensor wiring shield(s).
	2.	Ensure the shields are tied together and electrically isolated from the
		transmitter enclosure.
	3.	Only ground shield at the power supply end.
	4.	Ensure that the sensor shield(s) is electrically isolated from the
		surrounding grounded fixtures.
								Power
					848T
								Supply
		Sensor Wires
					Shield ground point

Option 2:

1.Connect sensor wiring shield(s) to the transmitter enclosure (only if the enclosure is grounded).

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

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

848T	Power
	Supply
Sensor Wires
	Shield ground points

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Grounded Thermocouple Inputs

1.Ground sensor wiring shield(s) at the sensor.

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

3.Do not connect the signal wiring shield to the sensor wiring shield(s).

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

			Power
	848T
			Supply

Sensor Wires

Shield ground points

Analog Device Inputs

1.Ground analog signal wire at the power supply of the analog devices.

2.Ensure that the analog signal wire and the fieldbus signal wire shields are electrically isolated from the transmitter enclosure.

3.Do not connect the analog signal wire shield to the fieldbus signal wire shield.

4.Ground fieldbus signal wire shield at the power supply end.

		4-20 mA loop			FOUNDATION
					fieldbus bus
								Power
AnalogDevice		Analog
				848T				Supply
Power Supply
		Device

Shield ground points

Transmitter Enclosure (optional)

Ground the transmitter in accordance with local electrical requirements.

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SWITCHES

Figure 2-8. Switch Location on the Rosemount 848T

NOT USED

SECURITY

SIMULATE ENABLE

Security

After configuring the transmitter, the data can be protected from unwarranted changes. Each 848T is equipped with a security switch that can be positioned “ON” to prevent the accidental or deliberate change of configuration data.

This switch is located on the front side of the electronics module and is labeled SECURITY.

See Figure 2-8 for switch location on the transmitter label.

Simulate Enable

The switch labeled SIMULATE ENABLE is used in conjunction with the Analog Input (AI) and Multiple Analog Input (MAI) function blocks. This switch is used to simulate temperature measurement.

Not Used

The switch is not functional.

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TAGGING	Commissioning Tag
	The 848T has been supplied with a removable commissioning tag that
	contains both the Device ID (the unique code that identifies a particular device
	in the absence of a device tag) and a space to record the device tag (the
	operational identification for the device as defined by the Piping and
	Instrumentation Diagram (P&ID)).
	When commissioning more than one device on a fieldbus segment, it can be
	difficult to identify which device is at a particular location. The removable tag,
	provided with the transmitter, can aid in this process by linking the Device ID
	to its physical location. The installer should note the physical location of the
	transmitter on both the upper and lower location of the commissioning tag.
	The bottom portion should be torn off for each device on the segment and
	used for commissioning the segment in the control system.
Figure 2-9. Commissioning Tag

Device ID

Device Tag to denote physical

location

Transmitter Tag

Hardware

•Tagged in accordance with customer requirements

•Permanently attached to the transmitter

Software

•The transmitter can store up to 32 characters

•If no characters are specified, the first 30 characters of the hardware tag will be used

Sensor Tag

Hardware

•A plastic tag is provided to record identification of eight sensors

•This information can be printed at the factory upon request

•In the field, the tag can be removed, printed onto, and reattached to the transmitter

Software

•If sensor tagging is requested, the Transducer Block SERIAL_NUMBER parameters will be set at the factory

•The SERIAL_NUMBER parameters can be updated in the field

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INSTALLATION

Using Cable Glands

Figure 2-10. Installing the 848T with Cable Glands

Using Conduit Entries

Figure 2-11. Installing the 848T with Conduit Entries

Use the following steps to install the 848T with Cable Glands:

1.Remove the junction box cover by unscrewing the four cover screws.

2.Run the sensor and power/signal wires through the appropriate cable glands using the pre-installed cable glands (see Figure 2-10).

3.Install the sensor wires into the correct screw terminals (follow the label on the electronics module).

4.Install the power/signal wires onto the correct screw terminals. Power is polarity insensitive, allowing the user to connect positive (+) or negative (–) to either Fieldbus wiring terminal labeled “Bus.”

5.Replace the enclosure cover and securely tighten all cover screws.

	Enclosure Cover	Sensor 7
		Sensor 5
	Screw (4)
		Sensor 3
		Sensor 1

Power/Signal

	Sensor 8
Cable Gland	Sensor 6
	Sensor 4
	Sensor 2

Use the following steps to install the 848T with Conduit Entries:

1.Remove the junction box cover by unscrewing the four cover screws.

2.Remove the five conduit plugs and install five conduit fittings (supplied by the installer).

3.Run pairs of sensor wires through each conduit fitting.

4.Install the sensor wires into the correct screw terminals (follow the label on the electronics module).

5.Install the power/signal wires into the correct screw terminals. Power is polarity insensitive, allowing the user to connect positive (+) or negative (–) to either Fieldbus wiring terminal labeled “Bus.”

6.Replace the junction box cover and securely tighten all cover screws.

	Sensor 3 and 4 Conduit		Sensor 7 and 8 Conduit
Enclosure		Sensor
Cover Screw	Sensors	5 and 6
		Conduit
	1 and 2		Power/Signal
	Conduit
			Conduit

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Section 3

Configuration

SAFETY MESSAGES

Warnings

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-1 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-2 Common Configurations for High Density Applications page 3-4 Block Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-7

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 (). Please 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.

Process leaks could result in death or serious injury.

•Do not remove the thermowell while in operation. Removing while in operation may cause process fluid leaks.

•Install and tighten thermowells and sensors before applying pressure, or process leakage may result.

Electrical shock could cause death or serious injury.

•If the sensor is installed in a high voltage environment and a fault condition or installation error occurs, high voltage may be present on transmitter leads and terminals.

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

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CONFIGURATION

Standard	Each FOUNDATION fieldbus configuration tool or host system has a different
	way of displaying and performing configurations. Some will use Device
	Descriptions (DDs) and DD Methods to make configuration and displaying of
	data consistent across host platforms.
	Unless otherwise specified, the 848T will be shipped with the following
	configuration (default):

Table 3-1. Standard

Configuration Settings

Transmitter

Configuration

Custom Configuration

Methods

Sensor Type(1)	Type J Thermocouple
Damping(1)	5 seconds
Measurement Units(1)	°C
Output(1)	Linear with Temperature
Line Voltage Filter(1)	60 Hz
Temperature Specific Blocks	•	Transducer Block (1)
FOUNDATION fieldbus Function Blocks	•	Analog Input (8)
	•	Multiple Analog Input (2)
	•	Input Selector (4)

(1) For all eight sensors

Refer to that systems documentation to perform configuration changes using a FOUNDATION fieldbus host or configuration tool.

NOTE

To make configuration changes, ensure that the block is Out of Service (OOS) by setting the MODE_BLK.TARGET to OOS, or set the SENSOR_MODE to Configuration.

The transmitter is available with the standard configuration setting. The configuration settings and block configuration may be changed in the field with the Emerson Process Management Systems DeltaV®, with AMSinside, or other FOUNDATION fieldbus host or configuration tool.

Custom configurations are to be specified when ordering.

For FOUNDATION fieldbus hosts or configuration tools that support device description (DD) methods, there are two configuration methods available in the Transducer block. These methods are included with the DD software.

•Sensor Configuration

•Sensor Input Trim (user input trim)

See the host system documentation for information on running DD methods from the host system. If the FOUNDATION fieldbus host or configuration tool does not support DD methods, refer to “Block Configuration” on page 3-7 for information on how to modify sensor configuration parameters.

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Alarms

Damping

Configure the Differential

Sensors

Configure Measurement

Validation

Use the following steps to configure the alarms, which are located in the Resource Function Block.

1.Set the resource block to OOS.

2.Set WRITE_PRI to the appropriate alarm level (WRITE_PRI has a selectable range of priorities from 0 to 15, see “Alarm Priority Levels” on page 3-11. Set the other block alarm parameters at this time.

3.Set CONFIRM_TIME to the time, in 1/32 of a millisecond, that the device will wait for confirmation of receiving a report before trying again (the device does not retry if CONFIRM_TIME is 0).

4.Set LIM_NOTIFY to a value between zero and MAX_NOTIFY. LIM_NOTIFY is the maximum number of alert reports allowed before the operator needs to acknowledge an alarm condition.

5.Enable the reports bit in FEATURES_SEL. (When Multi-bit alerts is enabled, every active alarm is visible for any of the eight sensors, generated by a PlantWeb alert. This is different than only viewing the highest priority alarm.)

6.Set the resource block to AUTO.

For modifying alarms on individual function blocks (AI or ISEL blocks), refer to Appendix D: Function Blocks.

Use the following steps to configure the damping, which is located in the Transducer Function Block.

1.Set Sensor Mode to Out of Service.

2.Change DAMPING to the desired filter rate (0.0 to 32.0 seconds).

3.Set Sensor Mode to In Service.

Use the following steps to configure the Differential Sensors:

1.Set Dual Sensor Mode to Out of Service.

2.Set Input A and Input B to the sensor values that are to be used in the differential equation diff = A–B. (NOTE: Unit types must be the same.)

3.Set the DUAL_SENSOR_CALC to either Not Used, Absolute, or INPUT A minus INPUT B.

4.Set Dual Sensor Mode to In Service.

Use the following steps to configure Measurement Validation:

1.Set mode to Disabled for specific sensor.

2.Select sample rate. 1-10 sec/sample is available. 1 second/sample is preferred for sensor degradation. The higher the number of seconds between samples, the more emphasis put on process variation.

3.Select Deviation Limit from 0 to 10 units. If deviation limit is exceeded, a status event will be triggered.

4.Select Increasing Limit. Sets the limit for increasing rate of change. If limit is exceeded, a status event will be triggered.

5.Select Decreasing Limit. Sets the limit for decreasing rate of change. If limit is exceeded, a status event will be triggered.

NOTE:

The decreasing limit selected is required to be a negative value.

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COMMON CONFIGURATIONS FOR HIGH DENSITY APPLICATIONS

Out_1

Out_2

Out_3

Out_4

Out_5

MAI Out_6

Function

Block Out_7

Out_8

6.Set the Deadband from 0 to 90%. This threshold is used to clear the PV status.

7.Set Status Priority. This determines what happens when the specific limit has been exceeded. No Alert - Ignores limit settings. Advisory - Sets Advisory Plant Web Alert, but does not do anything with PV status. Warning - Sets a Maintenance Plant Web Alert and sets PV status to uncertain. Failure - Sets A Failure Plant Web Alert and sets PV status to Bad.

8.Set mode to Enabled for specific sensor.

For the application to work properly, configure the links between the function blocks and schedule the order of their execution. The Graphical User Interface (GUI) provided by the FOUNDATION fieldbus host or configuration tool will allow easy configuration.

The measurement strategies shown in this section represent some of the common types of configurations available in the 848T. Although the appearance of the GUI screens will vary from host to host, the configuration logic is the same.

NOTE

Please ensure that the host system or configuration tool is properly configured before downloading the transmitter configuration. If configured improperly, the FOUNDATION fieldbus host or configuration tool could overwrite the default transmitter configuration.

Typical Profiling Application

Example: Distillation column temperature profile where all channels have the same sensor units (°C, °F, etc.).

1.Place the Multiple Analog Input (MAI) function block in OOS mode (set MODE_BLK.TARGET to OOS).

2.Set CHANNEL= “channels 1 to 8.” Although the CHANNEL_X parameters remain writable, CHANNEL_X can only be set = X when CHANNEL=1.

3.Set L_TYPE to direct or indirect.

4.Set XD_SCALE (transducer measurement scaling) to the appropriate upper and lower range values, the appropriate sensor units, and display decimal point.

5.Set OUT_SCALE (MAI output scaling) to the appropriate upper and lower range values, the appropriate sensor units, and display decimal point.

6.Place the MAI Function Block in auto mode.

7.Verify that the function blocks are scheduled.

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Monitoring Application with a Single Selection

Example: Average exhaust temperature of gas and turbine where there is a single alarm level for all inputs.

	Out_1		IN_1			Out
	Out_2		IN_2			Out_D
	Out_3		IN_3
	Out_4		IN_4
	Out_5		IN_5
MAI	Out_6		IN_6			ISEL
	Out_7		IN_7
Function						Function
Block	Out_8		IN_8			Block

1.Link the MAI outputs to the ISEL inputs.

2.Place the Multiple Analog Input (MAI) function block in OOS mode (set MODE_BLK.TARGET to OOS).

3.Set CHANNEL= “channels 1 to 8.” Although the CHANNEL_X parameters remain writable, CHANNEL_X can only be set = X when CHANNEL=1.

4.Set L_TYPE to direct or indirect.

5.Set XD_SCALE (transducer measurement scaling) to the appropriate upper and lower range values, the appropriate sensor units, and display decimal point.

6.Set OUT_SCALE (MAI output scaling) to the appropriate upper and lower range values, the appropriate sensor units, and display decimal point.

7.Place the MAI function block in auto mode.

8.Place the Input Selector (ISEL) function block in OOS mode by setting MODE_BLK.TARGET to OOS.

9.Set OUT_RANGE to match the OUT_SCALE in the MAI block.

10.Set SELECT_TYPE to the desired function (Maximum Value, Minimum Value, First Good Value, Midpoint Value, or Average Value).

11.Set the alarm limits and parameters if necessary.

12.Place the ISEL function block in auto mode.

13.Verify that the function blocks are scheduled.

Measuring Temperature Points Individually

	AI		Out
	Function		Out_D
	Block 1

				Out
AI
Function				Out_D
Block 8

Example: Miscellaneous monitoring of temperature in a “close proximity” where each channel can have different sensor inputs with different units and there are independent alarm levels for each input.

1.Place the first Analog Input (AI) function block in OOS mode (set MODE_BLK.TARGET to OOS).

2.Set CHANNEL to the appropriate channel value. Refer to “Alarm Priority Levels” on page 3-11 for a listing of channel definitions.

3.Set L_TYPE to direct.

4.Set XD_SCALE (transducer measurement scaling) to the appropriate upper and lower range values, the appropriate sensor units, and display decimal point.

5.Set OUT_SCALE (AI output scaling) to the appropriate upper and lower range values, the appropriate sensor units, and display decimal point.

6.Set the alarm limits and parameters if necessary.

7.Place the AI function block in auto mode.

8.Repeat steps 1 through 7 for each AI function block.

9.Verify that the function blocks are scheduled.

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Interfacing Analog Transmitters to FOUNDATION fieldbus

Transducer Block Configuration

Use the sensor configuration method to set the sensor type to mV – 2-wire for the applicable transducer block or follow these steps.

1.Set the MODE_BLK.TARGET to OOS mode, or set the SENSOR_MODE to configuration.

2.Set the SENSOR to mV.

3.Set the MODE_BLK.TARGET to AUTO, or set the SENSOR_MODE to operation.

Multiple Analog Input or Analog Input Block Configuration

Follow these steps to configure the applicable block.

1.Set the MODE_BLK.TARGET to OOS mode, or set the SENSOR_MODE to configuration.

2.Set CHANNEL to the transducer block configured for the analog input.

3.Set XD_SCALE.EU_0 to 20 Set XD_SCALE.EU_100 to 100

Set XD_SCALE.ENGUNITS to mV

4.SET OUT_SCALE to match the desired scale and units for the connected analog transmitter.

Flow Example: 0 – 200 gpm OUT_SCALE.EU_0 = 0 OUT_SCALE.EU_100 = 200 OUT_SCALE.ENGUNITS = gpm

5.Set L_TYPE to INDIRECT.

6.Set the MODE_BLK.TARGET to AUTO, or set the SENSOR_MODE to operation.

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BLOCK CONFIGURATION

Rosemount 848T

Resource Block

The resource block defines the physical resources of the device including type of measurement, memory, etc. The resource block also defines functionality, such as shed times, that is common across multiple blocks. The block has no linkable inputs or outputs and it performs memory-level diagnostics.

Table 3-2. Resource Block Parameters

Number	Parameter	Description
01	ST_REV	The revision level of the static data associated with the function block.
02	TAG_DESC	The user description of the intended application of the block.
03	STRATEGY	The strategy field can be used to identify grouping of blocks.
04	ALERT_KEY	The identification number of the plant unit.
05	MODE_BLK	The actual, target, permitted, and normal modes of the block. For further description, see the
		Mode parameter formal model in FF-890.
06	BLOCK_ERR	This parameter reflects the error status associated with the hardware or software components
		associated with a block. Multiple errors may be shown. For a list of enumeration values, see
		FF-890, Block_Err formal model.
07	RS_STATE	State of the function block application state machine. For a list of enumeration values, see
		FF-890.
08	TEST_RW	Read/write test parameter - used only for conformance testing.
09	DD_RESOURCE	String identifying the tag of the resource which contains the Device Description for the
		resource.
10	MANUFAC_ID	Manufacturer identification number - used by an interface device to locate the DD file for the
		resource.
11	DEV_TYPE	Manufacturer's model number associated with the resource - used by interface devices to
		locate the DD file for the resource.
12	DEV_REV	Manufacturer revision number associated with the resource - used by an interface device to
		locate the DD file for the resource.
13	DD_REV	Revision of the DD associated with the resource - used by the interface device to locate the
		DD file for the resource.
14	GRANT_DENY	Options for controlling access of host computer and local control panels to operating, tuning
		and alarm parameters of the block.
15	HARD_TYPES	The types of hardware available as channel numbers. The supported hardware type is:
		SCALAR_INPUT
16	RESTART	Allows a manual restart to be initiated.
17	FEATURES	Used to show supported resource block options. The supported features are: Unicode,
		Reports, Soft_Write_Lock, Hard_Write_Lock, and Multi-Bit Alarms.
18	FEATURE_SEL	Used to select resource block options.
19	CYCLE_TYPE	Identifies the block execution methods available for this resource. The supported cycle types
		are: SCHEDULED, and COMPLETION_OF_BLOCK_EXECUTION
20	CYCLE_SEL	Used to select the block execution method for this resource.
21	MIN_CYCLE_T	Time duration of the shortest cycle interval of which the resource is capable.
22	MEMORY_SIZE	Available configuration memory in the empty resource. To be checked before attempting a
		download.
23	NV_CYCLE_T	Minimum time interval specified by the manufacturer for writing copies of NV parameters to
		non-volatile memory. Zero means it will never be automatically copied. At the end of
		NV_CYCLE_T, only those parameters which have changed need to be updated in NVRAM.
24	FREE_SPACE	Percent of memory available for further configuration. Zero in preconfigured resource.
25	FREE_TIME	Percent of the block processing time that is free to process additional blocks.
26	SHED_RCAS	Time duration at which to give up on computer writes to function block RCas locations. Shed
		from RCas will never happen when SHED_RCAS = 0.
27	SHED_ROUT	Time duration at which to give up on computer writes to function block ROut locations. Shed
		from ROut will never happen when SHED_ROUT = 0.

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Table 3-2. Resource Block Parameters

Number	Parameter	Description
28	FAULT_STATE	Condition set by loss of communication to an output block, fault promoted to an output block
		or physical contact. When FAIL_SAFE condition is set, then output function blocks will
		perform their FAIL_SAFE actions.
29	SET_FSTATE	Allows the FAIL_SAFE condition to be manually initiated by selecting Set.
30	CLR_FSTATE	Writing a Clear to this parameter will clear the device FAIL_SAFE if the field condition has
		cleared.
31	MAX_NOTIFY	Maximum number of unconfirmed notify messages possible.
32	LIM_NOTIFY	Maximum number of unconfirmed alert notify messages allowed.
33	CONFIRM_TIME	The time the resource will wait for confirmation of receipt of a report before trying again. Retry
		will not happen when CONFIRM_TIME=0.
34	WRITE_LOCK	If set, all writes to static and non-volatile parameters are prohibited, except to clear
		WRITE_LOCK. Block inputs will continue to be updated.
35	UPDATE_EVT	This alert is generated by any change to the static data.
36	BLOCK_ALM	The BLOCK_ALM is used for all configuration, hardware, connection failure or system
		problems in the block. The cause of the alert is entered in the subcode field. The first alert to
		become active will set the Active status in the Status attribute. As soon as the Unreported
		status is cleared by the alert reporting task, another block alert may be reported without
		clearing the Active status, if the subcode has changed.
37	ALARM_SUM	The current alert status, unacknowledged states, unreported states, and disabled states of
		the alarms associated with the function block.
38	ACK_OPTION	Selection of whether alarms associated with the block will be automatically acknowledged.
39	WRITE_PRI	Priority of the alarm generated by clearing the write lock.
40	WRITE_ALM	This alert is generated if the write lock parameter is cleared.
41	ITK_VER	Major revision number of the interoperability test case used in certifying this device as
		interoperable. The format and range are controlled by the Fieldbus FOUNDATION.
42	DISTRIBUTOR	Reserved for use as distributor ID. No FOUNDATION enumerations defined at this time.
43	DEV_STRING	This is used to load new licensing into the device. The value can be written but will always
		read back with a value of 0.
44	XD_OPTIONS	Indicates which transducer block licensing options are enabled.
45	FB_OPTIONS	Indicates which function block licensing options are enabled.
46	DIAG_OPTIONS	Indicates which diagnostics licensing options are enabled.
47	MISC_OPTIONS	Indicates which miscellaneous licensing options are enabled.
48	RB_SFTWR_REV_MAJOR	Major revision of software that the resource block was created with.
49	RB_SFTWR_REV_MINOR	Minor revision of software that the resource block was created with.
50	RB_SFTWR_REV_BUILD	Build of software that the resource block was created with.
51	RB_SFTWR_REV_ALL	The string will contains the following fields:
		Major rev: 1-3 characters, decimal number 0-255
		Minor rev: 1-3 characters, decimal number 0-255
		Build rev: 1-5 characters, decimal number 0-255
		Time of build: 8 characters, xx:xx:xx, military time
		Day of week of build: 3 characters, Sun, Mon, …
		Month of build: 3 characters, Jan, Feb.
		Day of month of build: 1-2 characters, decimal number 1-31
		Year of build: 4 characters, decimal
		Builder: 7 characters, login name of builder
52	HARDWARE_REV	Hardware revision of that hardware that has the resource block in it.
53	OUTPUT_BOARD_SN	Output board serial number.
54	FINAL_ASSY_NUM	The same final assembly number placed on the label.
55	DETAILED_STATUS	Indicates the state of the transmitter. NOTE: Will be writable when PWA_SIMULATE is On
		during simulation mode.
56	SUMMARY_STATUS	An enumerated value of repair analysis.
57	MESSAGE_DATE	Date associated with the MESSAGE_TEXT parameter
58	MESSAGE_TEXT	Used to indicate changes made by the user to the device’s installation, configuration, or
		calibration.
59	SELF_TEST	Used to self test the device. Tests are device specific.

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