Fluke 726 Service Manual

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Page 1

724/725/726

Calibrators

Calibration Manual

PN 667581 September 1999 Rev. 2, 2/06

Page 2

LIMITED WARRANTY AND LIMITATION OF LIABILITY

Each Fluke product is warranted to be free from defects in material and workmanship under normal use and service. The warranty period is three years and begins on the date of shipment. Parts, product repairs, and services are warranted for 90 days. This warranty extends only to the original buyer or end-user customer of a Fluke authorized reseller, and does not apply to fuses, disposable batteries, or to any product which, in Fluke's opinion, has been misused, altered, neglected, contaminated, or damaged by accident or abnormal conditions of operation or handling. Fluke warrants that software will operate substantially in accordance with its functional specifications for 90 days and that it has been properly recorded on non-defective media. Fluke does not warrant that software will be error free or operate without interruption.

Fluke authorized resellers shall extend this warranty on new and unused products to end-user customers only but have no authority to extend a greater or different warranty on behalf of Fluke. Warranty support is available only if product is purchased through a Fluke authorized sales outlet or Buyer has paid the applicable international price. Fluke reserves the right to invoice Buyer for importation costs of repair/replacement parts when product purchased in one country is submitted for repair in another country.

Fluke's warranty obligation is limited, at Fluke's option, to refund of the purchase price, free of charge repair, or replacement of a defective product which is returned to a Fluke authorized service center within the warranty period.

To obtain warranty service, contact your nearest Fluke authorized service center to obtain return authorization information, then send the product to that service center, with a description of the difficulty, postage and insurance prepaid (FOB Destination). Fluke assumes no risk for damage in transit. Following warranty repair, the product will be returned to Buyer, transportation prepaid (FOB Destination). If Fluke determines that failure was caused by neglect, misuse, contamination, alteration, accident, or abnormal condition of operation or handling, including overvoltage failures caused by use outside the product’s specified rating, or normal wear and tear of mechanical components, Fluke will provide an estimate of repair costs and obtain authorization before commencing the work. Following repair, the product will be returned to the Buyer transportation prepaid and the Buyer will be billed for the repair and return transportation charges (FOB Shipping Point).

THIS WARRANTY IS BUYER'S SOLE AND EXCLUSIVE REMEDY AND IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. FLUKE SHALL NOT BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR CONSEQUENTIAL DAMAGES OR LOSSES, INCLUDING LOSS OF DATA, ARISING FROM ANY CAUSE OR THEORY.

Since some countries or states do not allow limitation of the term of an implied warranty, or exclusion or limitation of incidental or consequential damages, the limitations and exclusions of this warranty may not apply to every buyer. If any provision of this Warranty is held invalid or unenforceable by a court or other decision-maker of competent jurisdiction, such holding will not affect the validity or enforceability of any other provision.

Fluke Corporation P.O. Box 9090 Everett, WA 98206-9090 U.S.A.

Fluke Europe B.V. P.O. Box 1186 5602 BD Eindhoven The Netherlands

11/99

Page 3

Title Page

Introduction........................................................................................................ 1

Contacting Fluke................................................................................................ 1

Read First – Safety Information......................................................................... 2

International Symbols ........................................................................................ 3

Specifications..................................................................................................... 4

DC Voltage Measurement (724 and 725)...................................................... 4

DC Voltage Measurement and Source (726)................................................. 4

DC Voltage Source (724 and 725) ................................................................ 4

DC mA Measurement and Source (724 and 725)

(Measurement only for 724)....................................................................... 4

DC mA Measurement and Source (726) ....................................................... 5

Ohms Measurement (724 and 725) ............................................................... 5

Ohms Measurement (726) ............................................................................. 5

Ohms Source (724 and 725) .......................................................................... 5

Ohms Source (726)........................................................................................ 6

Frequency Measurement (725)...................................................................... 6

Frequency Measurement (726)...................................................................... 6

Frequency Source (725) ................................................................................ 6

Frequency Source (726) ................................................................................ 7

Millivolt Measurement and Source (724 and 725)........................................ 7

Temperature, Thermocouples (724 and 725)................................................. 7

Temperature, Thermocouples (726) .............................................................. 8

Temperature, RTD Ranges, and Accuracies (724 and 725) .......................... 9

RTD Accuracy (Read and Source) (ITS-90) (726)........................................ 10

Loop Power Supply ....................................................................................... 11

Pressure Measurement (725 and 726) ........................................................... 11

Pulse Read and Pulse Source (726) ............................................................... 11

Pressure Units Availability (725) .................................................................. 11

General Specifications................................................................................... 12

Cleaning the Calibrator...................................................................................... 12

Replacing the Batteries ...................................................................................... 12

Fuses .................................................................................................................. 13

Remote Control Interface (725 and 726) ........................................................... 14

Serial Command List (726)................................................................................ 17

Required Equipment .......................................................................................... 22

Performance Tests.............................................................................................. 24

Preparing for the Performance Tests ............................................................. 24

Upper Display Voltage Measurement Tests .................................................. 25

Lower Display mV/TC Measurement Tests .................................................. 26

Lower Display Voltage Measurement Tests.................................................. 27

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724/725/726

Calibration Manual

Upper Display mA Measurement Tests......................................................... 28

Lower Display mA Measurement Tests (725 and 726)................................. 29

Lower Display Frequency Measurement Test (725 and 726) ....................... 30

Lower Display Frequency Source Test (725 and 726) .................................. 31

Lower Display 4-Wire Resistance Measurement Tests................................. 32

Lower Display 3-Wire RTD Measurement ................................................... 33

Lower Display Thermocouple Measurement Tests....................................... 34

Lower Display Thermocouple Source Test ................................................... 35

Lower Display mA Source Tests (725 and 726) ........................................... 36

Lower Display mV Source Tests................................................................... 37

Lower Display Voltage Source Tests ............................................................ 37

Lower Display Ohms Source Tests ............................................................... 38

Pressure Module Input (725/726).................................................................. 39

Calibration Adjustment...................................................................................... 39

Setup.............................................................................................................. 39

Initiating Communication (724 and 725) ...................................................... 40

Calibration Adjustment Procedures (724 and 725) ....................................... 41

Cal Volts Input .......................................................................................... 41

Cal Volts Output ....................................................................................... 42

Cal mA Input (Fluke 725 Only) ................................................................ 43

Cal mA Output (725 Only) ....................................................................... 44

Cal mV Input............................................................................................. 45

Cal mV Output .......................................................................................... 46

Cal Thermocouples ................................................................................... 47

Cal Ohms Hi Source.................................................................................. 48

Cal Ohms Low Source .............................................................................. 49

Cal RTD Low Range................................................................................. 50

Cal RTD Hi Range .................................................................................... 51

Cal ISO Volts ............................................................................................ 52

Cal ISO mA............................................................................................... 53

Calibration Adjustment Procedures (726) ..................................................... 54

Initiating Communication ......................................................................... 54

Calibrating Isolated mA Input................................................................... 55

Calibrating Isolated Voltage Input ............................................................ 56

Calibrating mA Input ................................................................................ 57

Calibrating mA Output.............................................................................. 58

Calibrating Voltage Input.......................................................................... 59

Calibrating Voltage Output ....................................................................... 60

Calibrating Low Ohms Source.................................................................. 61

Calibrating High Ohms Source ................................................................. 62

Calibrating Ohms Measure........................................................................ 63

Calibrating Thermocouple mV Output ..................................................... 64

Calibrating Thermocouple mV Input ........................................................ 65

Calibrating Thermocouple CJC:................................................................ 66

Replaceable Parts............................................................................................... 67

Page 5

List of Tables

Table Title Page

1. International Symbols ............................................................................................ 3

2. Upper Display Remote Commands (725) .............................................................. 14

3. Lower Display Remote Commands (725).............................................................. 15

4. Remote Commands for Sensor Selection (725) ..................................................... 16

5. Serial Command List-726 ...................................................................................... 17

6. Required Equipment and Software ........................................................................ 23

7. Upper Display Voltage Readings........................................................................... 25

8. Lower Display mV Readings ................................................................................. 26

9. Lower Display Voltage Readings .......................................................................... 27

10. Upper Display mA Readings.................................................................................. 28

11. Lower Display mA Readings ................................................................................. 29

12. Lower Display 4-Wire Resistance Readings.......................................................... 32

13. Type J Thermocouple Readings............................................................................. 34

14. Lower Display Thermocouple Source Readings.................................................... 35

15. Lower Display mA Source Readings ..................................................................... 36

16. Lower Display mV Source Readings ..................................................................... 37

17. Lower Display Voltage Source Readings .............................................................. 37

18. Lower Display Ohms Source Readings.................................................................. 38

19. Replacement Parts.................................................................................................. 67

iii

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724/725/726

Calibration Manual

Page 7

List of Figures

Figure Title Page

1. Replacing the Batteries and Replaceable Fuses ..................................................... 13

2. Upper Display Voltage Test Connections.............................................................. 25

3. Lower Display mV and Voltage Test Connections................................................ 26

4. Upper Display mA Test Connections..................................................................... 28

5. Lower Display mA Test Connections .................................................................... 29

6. Lower Display Frequency Test Connections ......................................................... 30

7. Lower Display Frequency Source Test Connections ............................................. 31

8. Lower Display 4-Wire Resistance Test Connections............................................. 32

9. Lower Display 3-Wire Resistance Test Connections............................................. 33

10. Lower Display Thermocouple Test Connections................................................... 34

11. Lower Display mA Source Test ............................................................................. 36

12. Lower Display Ohms Source Test Connections.................................................... 38

13. Volts Input Calibration Connections...................................................................... 41

14. Volts Output Calibration Connections ................................................................... 42

15. mA Input Calibration Connections ........................................................................ 43

16. mA Output Calibration Connections...................................................................... 44

17. mV Input Calibration Connections ........................................................................ 45

18. mV Output Calibration Connections...................................................................... 46

19. Thermocouples Calibration Connections ............................................................... 47

20. Ohms Hi Source Calibration Connections ............................................................. 48

21. RTD Low Range Calibration Connections ............................................................ 50

22. ISO Volts Calibration Connections........................................................................ 52

23. ISO mA Calibration Connections .......................................................................... 53

24. Isolated mA Input Calibration Connections........................................................... 55

25. Isolated Voltage Input Calibration Connections .................................................... 56

26. mA Input Calibration Connections ........................................................................ 57

27. mA Output Calibration Connections...................................................................... 58

28. Voltage Input Calibration Connections.................................................................. 59

29. Voltage Output Calibration Connections ............................................................... 60

30. Low Ohms Source Calibration Connections.......................................................... 61

31. High Ohms Source Calibration Connections ......................................................... 62

32. Ohms Measure Calibration Connections................................................................ 63

33. Thermocouple mV Output Calibration Connections.............................................. 64

34. Thermocouple mV Input Calibration Connections ................................................ 65

35. Thermocouple CJC Calibration Connections......................................................... 66

36. Replacement Parts.................................................................................................. 68

Page 8

724/725/726

Calibration Manual

Page 9

Introduction

The information provided in this manual is for the use of qualified personnel only. Do not perform the verification tests or calibration procedures described in this manual unless you are qualified to do so.

This Calibration Manual provides the following information for the Fluke 724 Temperature Calibrator and the Fluke 725 and 726 Multifunction Process Calibrators (also referred to as "the Calibrator" and/or “the UUT”):

• Precautions and safety information

• Equipment required for performance tests and calibration

• Specifications

• Basic maintenance (cleaning, batteries, and fuses)

• Instructions for using the remote control interface

• Performance test procedures

• Calibration procedures

• List of replaceable parts

For complete operating instructions, refer to the appropriate Users Manual (located on the CD-ROM shipped with the instrument).

The Calibrator contains parts that can be damaged by static discharge. No procedure in this document requires the case to be opened. If you do so, follow the standard practices for handling static sensitive devices.

XWWarning

Caution

Contacting Fluke

To locate an authorized service center, visit us on the World Wide Web at

www.fluke.com or call Fluke using any of the following numbers:

• USA: 1-888-44-FLUKE (1-888-443-5853)

• Canada: 1-800-36-FLUKE (1-800-363-5853)

• Europe: +31 402-675-200

• Japan: +81-3-3434-0181

• Singapore: +65-738-5655

• Anywhere in the world: +1-425-446-5500

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724/725/726

Calibration Manual

Read First – Safety Information

In this calibration manual, a Warning identifies conditions and actions that pose hazard(s) to the user. A Caution identifies conditions and actions that may damage the Calibrator or the test instruments.

XWWarnings

To avoid possible electric shock or personal injury:

•

DO NOT use the Calibrator if it looks damaged.

•

Follow all safety procedures for the test and calibration equipment you use.

•

Examine the Calibrator before use. Look for cracks in the case, missing plastic, or damaged insulation around the connectors.

• Inspect the test leads for damaged insulation or exposed metal. Check for

test lead continuity. Replace damaged test leads as necessary.

• Do not use the Calibrator if it operates abnormally. Protection may be

impaired. When in doubt, have the instrument serviced.

• Do not apply more than the rated voltage, as marked on the Calibrator,

between terminals or between any terminal and earth ground.

• Never touch the probes to a voltage source when the test leads are plugged

into the current terminals.

• Select the proper function and range for each measurement.

• Disconnect the test leads before changing to another measure or source

function.

• When using probes, keep fingers behind the finger guards on the probes.

• Use caution when working above 30 V ac rms, 42 V ac peak, or 60 V dc.

Such voltages pose a shock hazard.

• Connect the common lead (COM) before connecting the live test lead. When

disconnecting test leads, disconnect the live test lead first.

• Always place the 5520A calibrator in Standby (STBY) mode between tests

and before handling the test connections or cables.

• Remove test leads from the Calibrator before opening the battery door.

• Do not operate the Calibrator around explosive gas, vapor, or dust.

• During normal operation, only use four properly installed AA batteries to

power the Calibrator.

• Make sure the battery door is closed and latched before you operate the

Calibrator.

• During calibration, use only specified calibration equipment listed in

Table 6.

(Continued on the next page)

Page 11

Calibrators

International Symbols

XWWarnings (cont)

• When servicing the Calibrator, use only specified replacement parts.

• To avoid false readings, which can lead to possible electric shock or personal

injury, replace the batteries as soon as the low battery indicator (

Caution

To avoid possible damage to the Calibrator or to the test instruments:

• Disconnect the power and discharge all high voltage capacitors before

testing resistance, diodes, or continuity.

• Use the proper jacks, function, and range for each measurement or

sourcing application.

B) appears.

International Symbols

International symbols used on the Calibrator and in this manual are explained in Table 1.

Table 1. International Symbols

Symbol Meaning Symbol Meaning

B F D

W X

Alternating current

Direct current

Alternating or direct current

Pressure

Refer to the manual. Important information.

Take appropriate precautions. Hazardous voltage may be present.

Do not dispose of this product as unsorted municipal waste. Contact Fluke or a qualified recycler for disposal.

J O P

)

Earth ground

ON/OFF

Conforms to European Union directives

Battery

Conforms to relevant Canadian Standards Association directives

Double insulated

Page 12

724/725/726

Calibration Manual

Specifications

DC Voltage Measurement (724 and 725)

30 V (upper display) 0.001 V 0.02 % + 2

20 V (lower display) 0.001 V 0.02 % + 2

90 mV (lower display) 0.01 mV 0.02 % + 2

Temperature coefficient -10 °C to +18 °C, 28 °C to 55 °C: ±0.005 % of range per °C

DC Voltage Measurement and Source (726)

Performance and accuracy are specified for one year after calibration, at operating temperatures of +18 °C to +28 °C (64 °F to 82 °F), in relative humidity to 90 %, after a 5 minute warm up period.

Note

A “count” is the amount by which the least significant digit can vary.

Range Resolution Accuracy (% of Reading + Counts)

Range Minimum Maximum

30 V (upper display) 0.000 V 30.000 V 0.010 % + 2 mV

20 V (lower display) 0.000 V 20.000 V 0.010 % + 2 mV

20 V (Source) 0.000 V 20.000 V 0.010 % + 2 mV

100 mV (Source) 0.000 V 100.000 mV 0.010 % + 10 µV

90 mV (Read) 0.000 V 90.000 mV 0.010 % + 10 µV

Maximum current output in voltage ranges is 1 mA with an output impedance of ≤ 1 Ω

Accuracy,

(% of Reading + Floor)

DC Voltage Source (724 and 725)

Range Resolution Accuracy (% of Reading + Counts)

100 mV 0.01 mV 0.02 % + 2

10 V 0.001 V 0.02 % + 2

Temperature coefficient -10 °C to +18 °C, 28 °C to 55 °C: ±0.005 % of range per °C Maximum load: 1 mA

DC mA Measurement and Source (724 and 725) (Measurement only for 724)

Range Resolution Accuracy ( % of Reading + Counts)

24 mA 0.001 mA 0.02 % + 2

Temperature coefficient -10 °C to +18 °C, +28 °C to 55 °C: ±0.005 % of range per °C Drive capability: 1000 Ω at 20 mA

Page 13

Calibrators

Specifications

DC mA Measurement and Source (726)

Accuracy,

Range Minimum Maximum

mA Read (Upper Display) 0.000 24.000 0.010 % + 2 µA

mA Read (Lower Display) 0.000 24.000 0.010 % + 2 µA

mA Source 0.000 24.000 0.010 % + 2 µA

Maximum load on, mA source is 1 kΩ. With the HART resistor on, maximum load is 750 Ω. Voltage input range on simulate mode is 5 to 30 V

(% of Reading +

Floor)

Ohms Measurement (724 and 725)

Ohms Range Accuracy, 4-Wire Accuracy*, 2-Wire, or 3-Wire

0 Ω to 400 Ω** ±0.1 Ω ±0.15 Ω

400 Ω to 1.5 kΩ ±0.5 Ω ±1.0 Ω

1.5 Ω to 3.2 kΩ ±1 Ω ±1.5 Ω

Excitation Current: 0.2 mA Maximum input voltage: 30 V Temperature coefficient -10 °C to +18 °C, +28 °C to 55 °C: ±0.005 % of range per °C

* 2-wire: Does not include lead resistance. ** For Firmware V1.7 or lower, the lowest range is 15 Ω to 400 Ω. 3-wire: Assumes matched leads with a total resistance not exceeding 100 Ω.

Ohms Measurement (726)

Ohms Range Minimum Maximum

Ohms Read (low) 0.00 400.00 0.015 % + 0.05 Ω

Ohms Read (high) 400.0 4000.0 0.015 % + 0.5 Ω

Accuracy

(% of Reading + Floor)

Ohms Source (724 and 725)

Ohms Range Excitation Current from Measurement Device

15 Ω to 400 Ω 0.15 mA to 0.5 mA ±0.15 Ω

15 Ω to 400 Ω 0.5 mA to 2 mA ±0.1 Ω

400 Ω to 1.5 kΩ 0.05 mA to 0.8 mA ±0.5 Ω

1.5 Ω to 3.2 kΩ 0.05 mA to 0.4 mA ±1 Ω

Accuracy

Temperature coefficient -10 °C to +18 °C, 28 °C to 55 °C: ±0.005 % of resistance range per °C

Resolution

15 to 400 Ω 0.1 Ω

400 to 3.2 kΩ 1 Ω

Page 14

724/725/726

Calibration Manual

Ohms Source (726)

Ohms Range Minimum Maximum

Ohms Source (low)

Ohms Source (high)

Unit is compatible with smart transmitters and PLCs. Frequency response is ≤ 5 mS

5.0 400.0 0.1 to 0.5 mA

5.0 400.0 0.5 to 3 mA

400 1500 0.05 to 0.8 mA

1500 4000 0.05 to 0.4 mA

Excitation Current from

Measurement Device

(% of Reading +

0.015 % + 0.1 Ω

0.015 % + 0.05 Ω

0.015 % + 0.5 Ω

Frequency Measurement (725)

Range Resolution Accuracy

2.0 to 1000.0 CPM 0.1 CPM ± (0.05 % + 1 count)

1 to 1000 Hz 0.1 Hz ± (0.05 % + 1 count)

1.0 to 10.0 kHz 0.01 kHz ± (0.05 % + 1 count)

Sensitivity: 1 V peak-to-peak minimum Waveform: Squarewave

Frequency Measurement (726)

Accuracy

Floor)

Accuracy

Range Minimum Maximum

CPM Read 2.0 1000.0 0.05 % + 0.1 CPM

Hz Read 1.0 1000.0 0.05 % + 0.1 Hz

KHz Read 1.00 15.00 0.05 % + 0.01 KHz

(% of Reading +

Floor)

Frequency Source (725)

Range Resolution Accuracy (% of output frequency)

2.0 to 1000.0 CPM 0.1 CPM ± 0.05 %

1 to 1100 Hz 1 Hz ± 0.05 %

1.0 to 10.0 kHz 0.1 kHz ± 0.25 %

Waveform: 5 V p-p squarewave, -0.1 V offset

Page 15

Calibrators

Specifications

Frequency Source (726)

Range Minimum Maximum Accuracy

CPM Source 2.0 1000 0.05 %

Hz Source 1.0 1000.0 0.05 %

KHz Source

1.0 10.00 0.25 %

10.00 15.00 0.50 %

Millivolt Measurement and Source (724 and 725)

Range* Resolution Accuracy

-10 mV to +75 mV 0.01 mV ±(0.025 % + 1 count)

Maximum input voltage: 30 V Temperature coefficient -10 °C to +18 °C, 28 °C to 55 °C: ±0.005 % of range per °C

*Select this function by pressing T. The signal is available at the thermocouple miniplug connector.

Temperature, Thermocouples (724 and 725)

Type Range (°C) Measure and Source Accuracies (°C)

Resolution: J, K, T, E, L, N, U: 0.1 °C, 0.1 °F B, R, S: 1 °C, 1 °F * For Firmware V1.7 or lower, the type N TC has 400 °C as the upper limit.

-200 to 0

0 to 1200

-200 to 0

0 to 1370

-200 to 0 0 to 400

-200 to 0 0 to 950

-20 to 0

0 to 500

500 to 1750

-20 to 0

0 to 500

500 to 1750

600 to 800

800 to 1000

1000 to 1800

-200 to 0 0 to 900

-200 to 0 0 to 400

-200 to 0

0 to 1300

1.0

0.7

1.2

0.8

1.2

0.8

0.9

0.7

2.5

1.8

1.4

2.5

1.8

1.5

2.2

1.8

1.4

0.85

0.7

1.1

0.75

1.5

0.9

Page 16

724/725/726

Calibration Manual

Temperature, Thermocouples (726)

Type Minimum Maximum

-210 0.0 0.6 0.4

XK -200 800 0.4 0.2

Thermocouple in mV read -10 mV to 75 mV

Thermocouple in mV source -10 mV to 75 mV

Maximum current output in voltage ranges is 1 mA with an output impedance of ≤ 1 Ω CJC error outside of 23 ± 5 °C is 0.05 °C / °C

0.0 800 0.4 0.2 800 1200 0.5 0.3

-200 0.0 0.8 0.6

0.0 1000 0.5 0.3 1000 1372 0.7 0.5

-250 0.0 0.8 0.6

0.0 400 0.4 0.2

-250 -100 0.8 0.6

-100 1000 0.4 0.4

-20 0.0 2.0 1.8

0.0 1767 1.4 1.2

-20 0.0 2.0 1.8

0.0 1767 1.4 1.2 600 800 1.4 1.2 800 1000 1.5 1.3 1000 1820 1.7 1.5

0.0 1000 0.8 0.6 1000 2316 2.5 2.3

-200 0.0 0.45 0.25

0.0 900 0.4 0.2

-200 0.0 0.7 0.5

0.0 600 0.45 0.25

-200 0.0 1.0 0.8

0.0 1300 0.6 0.4

0.0 800 1.1 0.9 800 2500 2.3 2.1

Range Accuracy

CJC ON

Accuracy

CJC OFF

Accuracy

0.015 % + 10 µV (% of Reading +

Floor)

0.015 % + 10 µV (% of Reading +

Floor)

Page 17

Calibrators

Specifications

Temperature, RTD Ranges, and Accuracies (724 and 725)

Type

Ni120 -80 to 260 0.2 0.3 0.2 Pt100-385 - 200 to 800 0.33 0.5 0.33 Pt100-392 -200 to 630 0.3 0.5 0.3 Pt100-JIS -200 to 630 0.3 0.5 0.3

Pt200-385

Pt500-385

Pt1000-385

Resolution: 0.1 °C, 0.1 °F

Allowable excitation current (source): Ni120, Pt100-385, Pt100-392, Pt100-JIS, Pt200-385: .05 to .80 mA,Pt500-385: 0.05 to 0.80 mA; Pt1000-385: 0.05 to 0.40 mA

RTD Source: Addresses pulsed transmitters and PLCs with pulses as short as 5 ms. SN < 7624001 may

need modification for pulses less than 15 ms. *2-wire: Does not include lead resistance. 3-wire: Assumes matched leads with a total resistance not exceeding 100 Ω.

Range (°C)

-200 to 250 250 to 630

-200 to 500 500 to 630

-200 to 100 100 to 630

Measure

4-wire (°C)

0.2

0.8

0.3

0.4

0.2

Accuracy

Measure*

2- and 3-wire (°C)

0.3

1.6

0.6

0.9

0.4

0.5

Source (°C)

0.2

0.8

0.3

0.4

0.2

Page 18

724/725/726

Calibration Manual

RTD Accuracy (Read and Source) (ITS-90) (726)

Ni120 (672) -80.00 260.00 0.15

Range Minimum Maximum Accuracy

-200.00 100.00 0.15

Pt100 (385)

Pt100 (3926)

Pt100 (3916)

Pt200 (385)

Pt500 (385)

100.00 300.00 0.25

300.00 600.00 0.35

600.00 800.00 0.45

-200.00 100.00 0.15

100.00 300.00 0.25

300.00 630.00 0.35

-200.00 100.00 0.15

100.00 300.00 0.25

300.00 630.00 0.35

-200.00 100.00 0.75

100.00 300.00 0.85

300.00 630.00 0.95

-200.00 100.00 0.35

100.00 300.00 0.45

300.00 630.00 0.55

-200.00 100.00 0.15

Pt1000 (385)

CU10 -10.00 250.00 1.8

Notes: Read Accuracy is based on 4-wire input. For 3-wire input, add ± 0.05 Ω assuming all three RTD leads are matched.

Source Accuracy is based on 0.5 to 3.0 mA excitation current (0.1 mA for pt1000 range)

Resolution: 0.1 °C, 0.1 °F

Allowable excitation current (source): Ni120, Pt100-385, Pt100-392, Pt100-JIS, Pt200-385: .05 to .80 mA,Pt500-385: 0.05 to 0.80 mA; Pt1000-385: 0.05 to 0.40 mA

RTD Source: Addresses pulsed transmitters and PLCs with pulses as short as 5 ms. SN < 7624001 may

need modification for pulses less than 15 ms.

100.00 300.00 0.25

300.00 630.00 0.35

Page 19

Calibrators

Specifications

Loop Power Supply

Voltage: 24 V

Maximum current: 22 mA

Short circuit protected

Pressure Measurement (725 and 726)

Range Resolution Accuracy Units Mode (726 Only)

Determined by pressure module

5 digits

Determined by pressure module

psi, inH inH cmH cmH mbar, kg/cm inHg

O@4 °C,

O@20 °C, kPa,

O@4 °C,

O@20 °C, bar,

, mmHg,

Pushing A for 3 seconds stores present pressure value as an offset and subtracts it from the displayed value.

Pulse Read and Pulse Source (726)

Pulse Min Max Accuracy Frequency

Source 10,000

Read

100,000

1 Count 2 CPM to 10 kHz

Pressure Units Availability (725)

Unit Availability

psi Available on all pressure ranges

inH2O All ranges through 3000 psi

cmH2O All ranges through 1000 psi

bar 15 psi and above

mbar All ranges through 1000 psi

kPa Available on all pressure ranges

inHg Available on all pressure ranges

mmHg All ranges through 1000 psi

kg/cm2 15 psi and above

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General Specifications

Operating temperature 724 and 725 726

Storage temperature - 20 °C to 70 °C

Stability ± 0.005 % of range/°C outside of 23 ± 5 °C

Operating altitude 3000 meters above mean sea level

Relative Humidity (% RH operating without condensation)

Vibration Random, 2 g, 5 Hz to 500 Hz

Safety 724 and 725

726

Power requirements 4 AA alkaline batteries

Protection Class Pollution Degree II

-10 °C to 55 °C

-10 °C to 50 °C

90 % (10 to 30 °C) 75 % (30 to 40 °C) 45 % (40 to 50 °C) 35 % (50 to 55 °C) uncontrolled < 10 °C

EN 61010-1:1993, ANSI/ISA S82.01-1994; CAN/CSA C22.2 No 1010.1:1992 EN50082-1:1992 and EN55022: 1994 Class B Criteria A or B CSA C22.2 No 1010.1:1992

Size 96 x 200 x 47 mm (3.75 x 7.9 x 1.86 in)

Weight 650 gm (1 lb, 7 oz)

Cleaning the Calibrator

XWWarning

To avoid electric shock or damage to the Calibrator, never allow water inside the Calibrator’s case.

If the Calibrator requires cleaning, wipe it down with a cloth that is lightly dampened with water or a mild detergent.

Do not use aromatic hydrocarbons, chlorinated solvents, or methanol-based fluids when cleaning the Calibrator. To avoid damaging the case, never apply solvents to the Calibrator.

Replacing the Batteries

XWWarning

To avoid electric shock, remove the test leads from the Calibrator before opening the battery door. Close and latch the battery door before using the Calibrator.

To avoid false readings, which can lead to possible electric shock or personal injury, replace the batteries as soon as the low battery indicator (

B) appears.

When replacing the batteries, always use four new AA batteries. Never mix new and used batteries in the Calibrator.

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Calibrators

Fuses

Four AA alkaline batteries (ANSI/NEDA 15A or IEC LR6) are used to power the Calibrator. To replace the batteries, refer to Figure 1 and do the following:

1. Turn the Calibrator off, remove the test leads from the terminals, and hold the

Calibrator face down.

2. Using a flat-blade screwdriver, turn the battery door screws 1/4-turn

counterclockwise and remove the battery door.

3. Remove the batteries, then install new batteries. Be sure to follow the polarity

markings shown in the battery compartment.

4. Replace the battery door and secure it by turning the screws 1/4-turn clockwise.

Fuses

Over time, the input protection has been modified to increase reliability. There will either be self-resetting fuses, or replaceable fuses in sockets. The self-resetting fuses open when heated by a current overload, and close when they cool down. When an input’s fuse is open, the input’s functions will not work.

Figure 1. Replacing the Batteries and Replaceable Fuses

XWWarning

To avoid electrical shock:

• Remove the test leads from the calibrator before opening the

battery door. Close and latch the battery door before using the calibrator.

• Use only the specified replacement fuses listed under

“Replaceable Parts”.

• Do not allow water into the case.

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The time required for a self-resetting fuse to reset depends on the magnitude of the overload. If a self-resetting fuse does not reset, return the Calibrator to an authorized service center for repair.

If a replaceable fuse has been damaged, it needs to be replaced. The fuses can be removed and checked for resistance. A value of < 10 Ω is good.

The calibrator comes equiped with three 0.2 A 250 V socketed fuses.

• Problems while measuring with the right jacks indicate that F3 may have opened.

• Problems while measuring

or sourcing with the center jacks or the TC jacks

indicate that F2 may have opened.

• If you can’t measure or source current with the left jacks, F4 may have opened.

To access the fuses, refer to instructions under “Replacing the Batteries”. The fuse compartment is located below the battery compartment. Use needle-nosed pliers to remove them and test them with a multimeter. Replace the fuse with the proper replacement fuse and follow the directions for reassembling the Calibrator. Refer to Figure 1.

Remote Control Interface (725 and 726)

The Calibrator’s serial interface and remote control commands let you use a PC to remotely select Calibrator functions and read the Calibrator’s display. This remote interface is especially useful if you want to write your own calibration software.

The 726 remote control interface is always active.

To activate the 725 remote control interface, proceed as follows:

1. Turn off the UUT; then use the Fluke 700SC serial interface cable to connect the

UUT to a serial port on the PC.

2. Start the terminal communication software on the PC. Create a new connection with

the following properties:

• Bits per second: 9600

• Data bits: 8

• Parity: None

• Stop bits: 1

• Flow control: None

• Local echo on

3. Hold down the Calibrator’s M button while turning the Calibrator on.

4. Use the commands given in Tables 2 through 4 to remotely control the Calibrator.

Table 2. Upper Display Remote Commands (725)

Remote Command Description

i mA measurement

L mA Loop Power E Voltage measurement B Single broadcast of the most recent upper display value and units

( Single broadcast of most recent upper display value without header or units

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Table 3. Lower Display Remote Commands (725)

Remote Command Description

A mA measurement a mA source

I mA 2W Sim V Voltage measurement v Voltage source

M mV measurement m mV source

K kHz measurement k kHz source

H Hz measurement

h Hz source P CPM measurement p CPM source

O Ohms measurement (default 2W)

o Select Ohms source

W 2-wire measurement (Ohms and RTDs)

X 3-wire measurement (Ohms and RTDs) Y 4-wire measurement (Ohms and RTDs) T Thermocouple measurement (default Type J). Use “S” command to select a

sensor type.

t Thermocouple source (default Type J). Use “S” command to select a sensor type

C Selects Centigrade ( T/C-RTD)

F Selects Fahrenheit ( T/C-RTD)

R RTD measurement mode (default Pt100 385). Use “S” command to select a

sensor type

r RTD measurement mode (default Pt100 385). Use “S” command to select sensor

type. u Increment display source value d Decrement display source value < The < arrow key PC keyboard selects left arrow on 725 > The > arrow key PC keyboard selects right arrow on 725

0-9 Enter a source value using ASCII characters 0,1,2,...9,-,.terminated by <CR>

(carriage return)

-,. The 725 can receive a maximum of 10 characters prior to the carriage return.

<CR>

b Single Broadcast of most recent lower display value and units

) Single broadcast of most recent lower display value without header or units.

Remote Control Interface (725 and 726)

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Serial Input No. Thermocouple Type RTD Type

2 K Pt100 (385)

3 T Pt100 (3916)

4 E Pt200 (385)

5 R Pt500 (385)

6 S Pt1000 (385)

7 B Ni120

8 L -

9 U -

A N -

Table 4. Remote Commands for Sensor Selection (725)

Selection Entry

S 1 J Pt100 (3926)

B mV -

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Serial Command List (726)

Table 5 lists the serial commands for the 726 Calibrator. Refer to “Remote Control Interface (725 and 726)” for activation steps.

Table 5. Serial Command List-726

Command Response/Actions

*IDN? Returns the ID string

“FLUKE,726,0,{sw_rev}” where sw_revision is the firmware revision

FUNC? Returns {Upper},{Lower}

{Upper} responses (Channel 1)

DCI, DCI_LOOP, DCV, DCI_ERROR, DCI_ERROR_LOOP

{Lower} responses

DCI, DCMV, DCV, DCI_SIM, TC, RTD, FREQUENCY, PULSE_TRAIN

VAL? Returns the measured value with

base units for the upper and lower display

{upper_val},{upper_units},{lower_ val},{lower _units},

upper_units: V, A, PERCENT

lower _units: V, CEL, FAR, A, OHM, CPM, HZ, COUNT

Command

Arguments

Verify model

Answers with

Comment Ch 1 Ch 2

number and firmware revision

the configured function for the upper and lower display

X X

UPPER_MEAS 1 argument, valid

settings: DCI, DCI_LOOP, DCV, DCI_ERROR, DCI_ERROR_LOOP

Set upper channel measure mode X

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Table 5. Serial Command List-726 (cont.)

Command Response/Actions

Command

Arguments

OUT Arguments:

{value} {units}

Multipliers: u for micro, m for milli, and k for kilo are accepted.

Units:

-V used for mV and Volts, the V_range command can be used to switch ranges

-CEL used for RTD, TC AND TC mV

-FAR used for RTD and TC

-A used for mA (see SIM for mA SIM)

-OHM used for RTD ohms, RTD_TYPE must be set to ohms

-CPM used for frequency

-HZ used for HZ and KHZ frequency (unit will auto range)

-COUNT used for pulse

Comment Ch 1 Ch 2

Configures the output source function. If the {value} and {units} are valid, this command will change modes if necessary and set the output value to {value} and {units} in that mode.

OUT? Returns the output (source)

value with units or none.

FREQ_UNIT 1 argument: CPM,

Verify the

output function and units

Set the output

HZ or KHZ

frequency range

FREQ_UNIT? Returns CPM, HZ, KHZ Verify the

frequency range

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Table 5. Serial Command List-726 (cont.)

Serial Command List (726)

Command Response/Actions

Command

Arguments

LOWER_MEAS 1 argument, Valid

Modes:

DCI, DCMV, DCV, TC, RTD, FREQUENCY, PULSE_TRAIN

SIM 1 Argument {value}

Multipliers u for micro, m for milli, and k for kilo are accepted. A is for amps

SIM? Returns the simulate value in

Amps with units or none

Verify the SIM

V_RANGE 1 Argument VOLTS or

MVOLTS

V_RANGE? Returns the voltage range VOLTS

or MVOLTS

Verify the

Comment Ch 1 Ch 2

Configures the measurement function. Sets the specified measure mode

If the value is valid, this command will change modes if necessary and set the output value to {value} in that mode.

output

Sets the voltage range

voltage range

PULSE_FREQ 2 arguments

{number}{units}.

(units CPM ,Hz ,Khz)

PULSE_FREQ? Returns the pulse output

frequency with units.

Verify the pulse

FREQ_LEVEL 1 Argument, valid

values: 1-20V

FREQ_LEVEL? Returns the pulse output and

frequency output voltage 1-20V

TRIG Toggles the pulse mode and

totalize trigger for read and source.

TRIG? Returns the state of the pulse

mode trigger, TRIGGERED, UNTRIGGERED or NONE.

Verify the

Initialize

Verify TRIG

Sets the pulse output frequency and range

frequency

Sets the pulse output and frequency output voltage

frequency voltage level

totalized pulse measurement or output

state X

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Table 5. Serial Command List-726 (cont.)

Command Response/Actions

Command

Arguments

TC_TYPE One argument, valid

settings: B, C, E, J, K, L, N, R, S, T, U, BP, XK, MV

TC_TYPE? Returns TC type

B, C, E, J, K, L, N, R, S, T, U, BP, XK, MV

Verify TC type

TSENS_TYPE 1 argument TC or

RTD

TSENS_TYPE? Returns the sensor type TC or

RTD

Verify is set

CJC_STATE One argument ON

or OFF

CJC_STATE? Returns ON or OFF Verify CJC

RTD_TYPE 1 argument: NI120,

PT392_100, PT385_100, PTJIS_100, PT385_200, PT385_500, PT385_1000, CU_10, CUST1, CUST2, CUST3, OHMS

RTD_TYPE? Returns RTD type

NI120, PT392_100, PT385_100, PTJIS_100, PT385_200, PT385_500, PT385_1000, CU_10, CUST1, CUST2, CUST3, OHMS

Verify the

Comment Ch 1 Ch 2

Set TC type

Sets the sensor type TC or RTD

for RTD or TC

Thermocoupl e cold junction compensation

state

Sets RTD type

RTD type setting

CPRT_R0 2 arguments

{number} OHM. Sets the custom CPRT R0.

CPRT_R0? Returns CPRT R0 with units

OHM.

CPRT_MIN_T 2 arguments

{number} CEL.

RTD_TYPE must be either CUST1, CUST2 or CUST3

CPRT_MIN_T? Returns {number} CEL.

CPRT_MAX_T 2 arguments

{number} CEL.

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Table 5. Serial Command List-726 (cont.)

Serial Command List (726)

Command Response/Actions

Command

Arguments

Comment Ch 1 Ch 2

CPRT_MAX_T? Returns {number} CEL. X

CPRT_COEFA 1 argument. Sets the

CPRT_COEFA? Returns the custom CPRT

Coefficient A.

custom CPRT Coefficient A.

CPRT_COEFB 1 argument. Sets the

CPRT_COEFB? Returns the custom CPRT

Coefficient B.

custom CPRT Coefficient B.

CPRT_COEFC 1 argument. Sets the

custom CPRT Coefficient C.

CPRT_COEFC? Returns the custom CPRT

Coefficient C.

RTD_WIRE 1 argument, 2W, 3W or

4W. Sets RTD read wire.

RTD_WIRE? Returns RTD read wire. Verify

connection setting

TEMP_UNIT 1 argument. Sets

temperature units, CEL or FAR

TEMP_UNIT? Returns temperature units, CEL or

FAR

CUST1_ALIAS 1 argument, sets

screen name for CUST1 RTD.

CUST1_ALIAS? Returns screen name for CUST1

RTD

Verify RTD 1

CUST2_ALIAS 1 argument, sets

screen name for CUST2 RTD.

CUST2_ALIAS? Returns screen name for CUST2

RTD.

Verify RTD 2

CUST3_ALIAS1 1 argument, sets

screen name for CUST3 RTD.

CEL: Celsius

FAR: Fahrenheit

alias

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Table 5. Serial Command List-726 (cont.)

Command Response/Actions

CUST3_ALIAS? Returns screen name for CUST3

RTD.

Command

Arguments

Verify RTD 3

HART_ON Turns HART mode on. Switches in 250

HART_OFF Turns HART mode off. Switches out

HART? Returns state of hart mode, ON or

OFF

Comment Ch 1 Ch 2

alias

Ω resistor

250

X X

*CLS Clear the error queue X X

FAULT Returns error code FILO X X

ERROR CODES:

NONNUMERIC_ENRTY (100)

EBUFFER_OVERFLOW (101)

INVALID_UNITS_CODE (102)

ENTRY_OVER_RNG (103)

ENTRY_UNDER_RNG (104)

MISSING_PARM (105)

INVALID_UNIT_PARM (106)

INVALID_SENSOR_TYPE (108)

UNKNOWN_COMMAND (110)

BAD_PARM_VALUE (111)

INPUT_BUFF_OVERFLOW (112)

MSG_BUFF_OVERFLOW (113)

OUTPUT_BUFF_OVERFLOW (114)

OUTPUT_OVERLOAD (115)

CAL_START

Initiates a password protected calibration (password = 627)

Required Equipment

Equipment and software required to perform the procedures in this manual are identified in Table 6. If the recommended equipment model is not available, other equipment can be substituted if it meets the specifications indicated.

To avoid safety hazards and equipment damage during the calibration procedures, use the specified calibration equipment listed in Table 6. Using unspecified equipment can give unreliable results and pose safety hazards.

XWWarning

X X

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Equipment Minimum Specifications Recommended Model

Multi-Product Calibrator

MET/CAL® Metrology Software (see MET/CAL Installation and Upgrade Guide for minimum hardware requirements)

Digital Multimeter

Table 6. Required Equipment and Software

DC voltage: 0 V to 30 V Accuracy: ±0.005 %

DC current: 0 mA to 24 mA Accuracy: ±0.005 %

Temperature: Type-J thermocouple 90 day accuracy: ±0.2 °C

Resistance accuracy: ±0.006 % Frequency accuracy: ±0.01 %

Version 6.0 or later Contact Fluke for the latest version.

DC voltage: 0 V to 24 V Accuracy: ±0.0013 %

DC voltage: 0 mA to 24 mA Accuracy: ±0.005 %

Fluke Model 5520A Multi-Product Calibrator only−no substitute

Fluke 8508A

Required Equipment

Pressure Module (725 and 726)

Test Leads Two sets of stackable low thermal

Thermocouple Test Lead

Personal computer Windows® 3.1 or later with terminal

PC interface cable (725 and 726)

Calibration cable Fluke 724/725 Calibration Cable Fluke PN 1556747

Standard Thermometer 0.1 % accuracy

In working condition; for establishing communication only

EMF banana test leads

2 Type-J male miniplugs with ~12” (30.5 cm) of 20-gauge Type-J thermocouple wire

communication software

Fluke 700SC serial interface cable assembly (LEMO to DB-9 female)

Fluke 700PXX Series

2 red leads: Fluke PN 105809 2 black leads: Fluke PN 105806

Fluke Model 80CJ-M male miniplugs (package of two)

20-gauge Type-J thermocouple wire is available through an electronic supply outlet

486 (or later) IBM-compatible

Fluke PN 667425

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Performance Tests

XXWarning

Some of the performance tests involve the use of high voltages and should be performed by qualified personnel only.

To avoid electric shock, always set the calibration source (5520A) to Standby (STBY) mode between tests and before handling the test connections or test cables.

Performance tests confirm the complete operability of the Calibrator and check the accuracy of each function against the Calibrator’s specifications.

Note

If the Calibrator fails any performance test, it needs calibration adjustments. If the Calibrator continues to fail after calibration adjustments, send it to an authorized Fluke Service Center for repair.

The Calibrator’s performance and accuracy are specified for one year after calibration at operating temperatures of +18 °C to +28 °C (64 °F to 82 °F), in relative humidity to 90 %. The specifications assume the Calibrator has been warmed up for five minutes before use.

It is not necessary to open the case for the performance tests; no mechanical adjustments are necessary. Merely make the required connections, source the designated values, and determine if the reading on the Calibrator or the multimeter falls within the acceptable range indicated.

Preparing for the Performance Tests

Performance tests for the Calibrator can be performed manually, or they can be computer-automated (using Fluke Metrology Software). The Metrology Software automates all of the performance verification tasks, except for connection of the standards to the Calibrator. This document provides the procedures necessary for manual performance tests. Contact Fluke for information on Metrology Software.

These performance tests assume that the person performing them knows how to use the Calibrator and the required equipment.

Do not attempt to perform these tests unless you are qualified to do so.

Throughout the performance tests, “UUT” (unit under test) refers to the Calibrator; the word “multimeter” is reserved for the digital multimeter identified in the required equipment listed in Table 6.

Unless otherwise indicated, all connection diagrams for the verification tests in this manual showing a calibrator or digital multimeter use a Fluke 5520A Calibrator or Fluke 8508A DMM. If you are using a different DMM, make the connections appropriate for your instrument.

Notes

To prepare the UUT for the performance tests, do the following:

1. Make sure that you have the required equipment available, see Table 6.

2. Make sure the UUT has fresh batteries. See “Replacing the Batteries” earlier in this

manual.

3. Warm up the multimeter as required by its specifications.

4. Remove all test leads from the front of the UUT.

5. Make sure that the UUT is in a stable ambient temperature between 18 °C and 28 °C (64.4 °F and 82.4 °F) and that it has been warmed up for five minutes.

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Performance Tests

Upper Display Voltage Measurement Tests

1. Press RESET on the 5520A.

2. Press l on the UUT until V appears on the upper display.

3. Make the connections shown in Figure 2.

4. Set up the 5520A to output each of the voltages in Table 7 and verify that the UUT readings are within the limits shown.

5. Press STBY on the 5520A.

Figure 2. Upper Display Voltage Test Connections

Table 7. Upper Display Voltage Readings

5520A Outputs 724/725 UUT Readings 726 UUT Readings

0.000 V -0.002 V to +0.002 V -0.002 V to +0.002 V

15.000 V 14.995 V to 15.005 V 14.996 V to 15.004 V

30.000 V 29.992 V to 30.008 V 29.995 V to 30.005 V

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Lower Display mV/TC Measurement Tests

1. Press RESET on the 5520A.

2. Press V on the UUT until MEASURE and mV appear on the lower display.

3. Make the connections shown in Figure 3.

4. Set up the 5520A to output each of the voltages in Table 8 and verify that the UUT readings are within the limits shown.

5. Press STBY on the 5520A.

Figure 3. Lower Display mV and Voltage Test Connections

Table 8. Lower Display mV Readings

5520A Outputs 724/725 UUT Readings 726 UUT Readings

0.00 mV -0.02 mV to +0.02 mV -0.0100 mV to +0.010 mV

45.00 mV 44.97 mV to 45.03 mV 44.986 mV to 45.014 mV

90.00 mV 88.96 mV to 89.04 mV 88.981 mV to 89.019 mV

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Performance Tests

Lower Display Voltage Measurement Tests

1. Press RESET on the 5520A.

2. Press V on the UUT until MEASURE and V appear on the lower display.

3. Make the connections shown in Figure 3.

4. Set up the 5520A to output each of the voltages in Table 9 and verify that the UUT readings are within the limits shown.

5. Press STBY on the 5520A.

Table 9. Lower Display Voltage Readings

5520A Outputs 724/725 UTT Readings 726 UTT Readings

0.000 V -0.002 V to +0.002 V -0.002 V to +0.002 V

10.000 V 9.996 V to 10.004 V 9.997 V to 10.003 V

20.000 V 19.994 V to 20.006 V 19.996 V to 20.004 V

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Upper Display mA Measurement Tests

1. Press RESET on the 5520A.

2. Press l on the UUT until MEASURE and mA appear on the upper display.

3. Make the connections shown in Figure 4.

4. Set up the 5520A to output each of the voltages in Table 10 and verify that the UUT readings are within the limits shown.

5. Press STBY on the 5520A.

Figure 4. Upper Display mA Test Connections

Table 10. Upper Display mA Readings

5520A Settings 724/725 UUT Readings 726 UUT Readings

4.000 mA 3.997 mA to 4.003 mA 3.997 mA to 4.003 mA

12.000 mA 11.995 mA to 12.005 mA 11.997 mA to 12.003 mA

24.000 mA 23.993 mA to 24.007 mA 23.995 mA to 24.005 mA

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Performance Tests

Lower Display mA Measurement Tests (725 and 726)

1. Press RESET on the 5520A.

2. Press l on the UUT until MEASURE and mA appear on the lower display.

3. Make the connections shown in Figure 5.

4. Set up the 5520A to output each of the voltages shown in Table 11 and verify that the UUT readings are within the limits shown.

5. Press STBY on the 5520A.

Figure 5. Lower Display mA Test Connections

Table 11. Lower Display mA Readings

5520A Outputs 724/725 UUT Readings 726 UUT Readings

4.000 mA 3.997 mA to 4.003 mA 3.997 mA to 4.003 mA

12.000 mA 11.995 mA to 12.005 mA 11.997 mA to 12.003 mA

24.000 mA 23.993 mA to 24.007 mA 23.995 mA to 24.005 mA

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Lower Display Frequency Measurement Test (725 and 726)

1. Set the 5520A to source a 10 kHz, 1 V peak-to-peak square wave (use the blue softkey under the wave type to change the wave shape).

2. Press F on the UUT (Kfor 726) until MEASURE and kHz appear on the lower display.

3. Make the connections shown in Figure 6.

4. Verify that the UUT frequency reads between 9.98 kHz and 10.02 kHz.

5. Press STBY on the 5520A.

Figure 6. Lower Display Frequency Test Connections

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Performance Tests

Lower Display Frequency Source Test (725 and 726)

1. Press M on the UUT until SOURCE appears on the lower display.

2. Press F on the UUT (Kfor 726) until Hz appears on the lower display.

3. Configure the Fluke 8508A to measure frequency; then make the connections shown in Figure 7.

4. Use the arrow keys on the UUT to set the UUT output 10 kHz at 5 V and verify that the Fluke 8508A readings are within the limits 9.975 Hz to 10.025 kHz.

5. Press M on the UUT to disable the sourcing function.

Figure 7. Lower Display Frequency Source Test Connections

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Lower Display 4-Wire Resistance Measurement Tests

1. Press F on the UUT (Ron 726) until Ω appears on the lower display. If necessary, use M to get to the measure mode, and use X )to get to the 4W mode. (MEASURE should also appear on the lower display).

2. Set the 5520A to 2-wire output with 2-wire compensation off; then make the connections shown in Figure 8.

3. Set the 5520A to source the resistance values in Table 12 and verify that the UUT resistance readings are within the limits shown.

4. Press STBY on the 5520A.

Figure 8. Lower Display 4-Wire Resistance Test Connections

Table 12. Lower Display 4-Wire Resistance Readings

5520A Outputs 724/725 UUT Readings 726 UUT Readings

15.00 Ω 14.90 Ω to 15.10 Ω 14.94 Ω to 15.06 Ω

350.00 Ω 349.90 Ω to 350.10 Ω 359.90 Ω to 350.10 Ω

500.00 Ω 499.5 Ω to 500.5 Ω 499.375 Ω to 500.625 Ω

1500.0 Ω 1499.5 Ω to 1500.5 Ω 1499.2 Ω to 1500.8 Ω

3200.0 Ω 3199.0 Ω to 3201.0 Ω -

3800.0 Ω - 3798.9 Ω to 3801.1 Ω

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Performance Tests

Lower Display 3-Wire RTD Measurement

1. Press F on the UUT (R on the 726) until Ω appears on the lower display. If necessary, use M to select the measure mode, and use X (R on the 726) to get to the 3W mode. (MEASURE should also appear on the lower display.)

2. Set the 5520A to 2-wire output with 2-wire compensation off; then make the connections shown in Figure 9.

3. Set the 5520A to source 350 Ω and verify that the UUT resistance readings are within the 349.80 to 350.2 Ω.

4. Press STBY on the 5520A.

Figure 9. Lower Display 3-Wire Resistance Test Connections

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Lower Display Thermocouple Measurement Tests

1. Remove the test leads from the UUT terminals; then connect a Type-J thermocouple lead between the TC jack on the UUT and the TC jack on the 5520A, as shown in Figure 10.

2. Press T on the UUT until J appears on the lower display. If necessary, press D (use the configuration menu on the 726) so the temperature is displayed in °C.

3. Set the 5520A to output the Type-J thermocouple voltages shown in Table 13 and verify the UUT temperature readings are within the limits shown (values use the ITS90 curves).

4. Press STBY on the 5520A.

Figure 10. Lower Display Thermocouple Test Connections

Table 13. Type-J Thermocouple Readings

5520A Settings

(referenced to 0 °C)

0.0 °C (0.000 mV) -0.7 °C to +0.7 °C -0.4 °C to +0.4 °C

724/725 UUT Readings 726 UUT Readings (CJC On)

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Performance Tests

Lower Display Thermocouple Source Test

1. Set the 5520A to measure Type-J thermocouple voltages.

2. Press M on the UUT until SOURCE appears on the lower display. If necessary, press T on the UUT until J appears on the lower display and press D (use the configuration menu on the 726) so the temperature is displayed in °C.

3. Use the arrow keys to set the UUT outputs to the temperatures in Table 14 and verify that the 5520A temperature readings are within the limits shown.

4. Press STBY on the 5520A. Remove the TC lead from the 5520A and the UUT.

Table 14. Lower Display Thermocouple Source Readings

UUT Settings

0.0 °C -0.7 °C to +0.7 °C -0.4 °C to +0.4 °C

724/725

5520A Readings

(referenced to 0 °C)

726

Readings

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Calibration Manual

Lower Display mA Source Tests (725 and 726)

1. Press M on the UUT until SOURCE appears on the lower display; then press V until mA appears on the lower display. If necessary, press M until SOURCE appears on the lower display.

2. Set the Fluke 8508A to measure dc current.

3. Connect the UUT and the Fluke 8508A as shown in Figure 11.

4. Use the arrow keys on the UUT to set the UUT to the currents in Table 15 and verify that the Fluke 8508A readings are within the limits shown.

Figure 11. Lower Display mA Source Connections

Table 15. Lower Display mA Source Readings

UUT Outputs

4.000 mA 3.9972 mA to 4.0028 mA 3.9976 mA to 4.0024 mA

12.000 mA 11.9956 mA to 12.0044 mA 11.9968 mA to 12.0032 mA

24.000 mA 23.9932 mA to 24.0068 mA 23.9956 mA to 24.0044 mA

Fluke 8508A Readings

724/725

Fluke 8508A Readings

726

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Calibrators

Performance Tests

Lower Display mV Source Tests

1. Press M on the UUT until SOURCE appears on the lower display; then press V until mV appears on the lower display.

2. Set the Fluke 8508A to measure dc voltage in the 200 mV range.

3. Connect the UUT to the Fluke 8508A as shown in Figure 7.

4. Use the arrow keys on the UUT to set the UUT output to the current values in Table 16 and verify that the Fluke 8508A readings are within the limits shown.

5. Press Mon the UUT to disable the sourcing function.

Table 16. Lower Display mV Source Readings

UUT Outputs

0.00 mV -0.020 mV to +0.020 mV -0.010 mV to +0.010 mV

45.00 mV 44.970 mV to 45.030 mV 44.986 mV to 45.014 mV

100.00 mV 99.960 mV to 100.040 mV 99.980 mV to 100.020 mV

Fluke 8508A Readings

Lower Display Voltage Source Tests

1. Press M on the UUT until SOURCE appears on the lower display; then press V until V appears on the lower display.

2. Set the Fluke 8508A to measure dc voltage in the 20 V range.

3. Connect the UUT to the Fluke 8508A as shown in Figure 7.

4. Use the arrow keys on the UUT to set the UUT outputs to the currents in Table 17 and verify that the Fluke 8508A readings are within the limits shown. You can use a lower voltage range on the Fluke 8508A to verify the 0 V range.

Table 17. Lower Display Voltage Source Readings

UUT Outputs

0.000 V -0.002 V to +0.002 V -0.002 V to +0.002 V

Fluke 8508A Readings

724/725

726

Fluke 8508A Readings

726

Fluke 8508A Readings

5.000 V 4.9970 V to 5.0030 V -

10.000 V 9.9960 V to 10.0040 V 9.997 V to 10.003 V

19.000 V - 18.9961 V to 19.0039 V

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Lower Display Ohms Source Tests

1. Press F ( R on the 726) on the UUT until Ω appears on the lower display. If necessary, press M until SOURCE appears on the lower display.

2. Set the Fluke 8508A to measure 4-wire resistance.

3. Set the Fluke 8508A to 2 k range for 72x resistance < 400 Ω, to 20 kΩ range for 400 Ω or more.

4. Make the connections shown in Figure 12.

5. Use the arrow keys on the UUT to set the UUT output to the resistance values in Table 18 and verify that the Fluke 8508A readings are within the limits shown.

Figure 12. Lower Display Ohms Source Test Connections

Table 18. Lower Display Ohms Source Readings

UUT Settings

15.0 Ω 14.9 Ω to 15.1 Ω 14.94775 Ω to 15.05225 Ω 2 kΩ

360.0 Ω 359.9 Ω to 360.1 Ω 359.896 Ω to 360.104 Ω 2 kΩ

500 Ω 499.5 Ω to 500.5 Ω 499.375 Ω to 500.625 Ω 20 kΩ

1500 Ω 1499.5 Ω to 1500.5 Ω 1499.275 Ω to 1500.725 Ω 20 kΩ

3200 Ω 3199.0 Ω to 3201.0 Ω - 20 kΩ

3800 Ω - 3798.93 Ω to 3807.01 Ω 20 kΩ

Fluke 8508A Readings

724/725

Fluke 8508A Readings

726

Range

The performance tests for the 724 are now complete. Disconnect and secure all test equipment.

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Calibrators

Pressure Module Input (725/726)

1. Connect a Fluke 700 Series Pressure Module to the 5-pin LEMO connector at the top of the UUT; then press U.

2. Verify that the display first shows -----psi, then changes to a pressure value.

3. Disconnect the pressure module from the UUT.

The performance tests for the 725 and 726 are now complete. Disconnect and secure all test equipment.

Calibration Adjustment

The Calibrators have electronic calibration. There are no mechanical adjustments and the calibration is done case closed. The calibration is done via serial communications port, by sending and receiving commands and readings. For the 725 and 726 serial port connection, you may use the 700SC Serial Interface Cable, PN 667425. This will permit communication through the pressure port connection. The 724/725 Calibration Cable, PN 1556747 is required for the 724 the 10-pin header in the battery compartment.

Throughout these procedures, the Calibrators are referred to as “UUT” (Unit Under Test). Two methods of calibration are available for the UUT: using a serial-based program via a PC (see Table 6 for requirements), and using a Met/Cal calibration procedure. This manual only describes the serial-based PC program. The automated Met/Cal procedures are available from the Fluke Metrology Group. For more information on the automated Met/Cal procedures contact Fluke or visit the Fluke Web site at www.fluke.com

, and can be used with the 725 and 726.. This connects to

Setup

As long as the calibrators have been within at a stable temperature within the range of 18

ºC to 28 ºC for an hour or more, they only need 5 minutes to warm up. If temperature

conditions were previously below 10 allowed to stabilize for a minimum of 3 hours prior to calibration.

The Calibrators should be calibrated at the required interval (defined by the factory as 1 year).

Setup the PC and UUT as follows:

1. Ensure that the terminal communications software is installed on the PC (such as Hyper Terminal or PcPlus).

2. Connect the interface cable to the appropriate connector on the UUT. Remove the jumper beside the ten-pin connector when using the 724/725 Calibration Cable on a

725. Replace the jumper after calibration is complete.

3. Connect the 9-pin 'D' connector to the PC serial port. An adapter may be needed for PCs that use 25-pin 'D' serial connectors.

4. Verify the settings on the PC are as follows:

• Bits per second: 9600

• Data bits: 8

• Parity: None

ºC or higher then 40 ºC, then the Calibrator must be

• Stop bits: 1

• Flow control: None

• Local echo on

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Calibration Manual

To begin calibration, or to select a particular calibration step, type the cal step (letter or number), then press Enter on the PC keyboard. It is not necessary to run all of the calibration steps when in the calibration mode. However, for the 726, certain dependencies exist in that certain functions must be calibrated before others can be calibrated. These dependencies are related to calibration only.

You must first calibrate mV Input and mV Output before calibrating thermocouples for the 724, 725, and 726. At the end of each step on the calibration menu, the new calibration constants for that step are saved, but not actually used until power is recycled.

When calibrating a measurement function, you must enter an input signal. For the 724 and 725, when the signal is connected and stable, press the space bar to start the adjustment. For the 726, press the Enter key. Usually, the UUT will display a calibration constant, then prompt for a second input value. Apply the new input value, then press the space bar or Enter key depending on the Calibrator. After the adjustment is complete, press the proper key to return to the Calibration Menu.

When calibrating a source function, you must enter the value of a reading. Type in the numerical value of the calibration desired. This will put the UUT into the desired calibration mode. When entering the calibration data for any source mode calibration, be sure to enter the value in the units listed, but don't enter the units (mV, mA, etc.). After the adjustment is complete, press the proper key to return to Calibration Menu. The calibration values will vary slightly, unit to unit. The constants used in this procedure may not appear exactly the same as on your UUT, but they should be approximately the same.

Initiating Communication (724 and 725)

Starting with the UUT off, push and hold Q while turning the UUT on. Continue to hold Q until "Cal mode" is displayed. “Enter Password:" appears on the display of all Calibrators that have firmware version V1.91 or higher. A password has been added to prevent users from accidentally changing the calibration of the Calibrator. The password for all 724 Calibrators is 427. The password for all 725 Calibrators is 527.

The calibration menus, as seen on the PC screen, are as follows:

725 Calibration Menu

Calibrate Menu 1 - Cal Volts Input 2 - Cal Volts Output 3 - Cal mA Input 4 - Cal mA Output 5 - Cal mV Input 6 - Cal mV Output 7 - Cal Thermocouples 8 - Cal Ohms Hi Source 9 - Cal Ohms Low Source A - Cal RTD LOW Range B - Cal RTD HI Range C - Cal ISO Volts D - Cal ISO mA

Enter Selection :

724 Calibration Menu

Calibrate Menu 1 - Cal Volts Input 2 - Cal Volts Output 3 - Cal mV Input 4 - Cal mV Output 5 - Cal Thermocouples 6 - Cal Ohms Hi Source 7 - Cal Ohms Low Source 8 - Cal RTD LOW Range 9 - Cal RTD HI Range A - Cal ISO Volts B - Cal ISO mA

Enter Selection :

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Calibrators

Calibration Adjustment

Calibration Adjustment Procedures (724 and 725)

The following sections detail the calibration procedures for the 724 and 725.

Cal Volts Input

Connect the UUT as shown in Figure 13.

Figure 13. Volts Input Calibration Connections

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From the Calibration Menu, type the cal step for Cal Volts Input. The PC displays:

Enter 0 Volts - press “ the proper key” to continue

Set the Fluke 5520A to output 0.0000 V, then press the space bar. After a short while, the following calibration constant and prompt are displayed on the PC:

Offset = -40

Enter 10.00 Volts - press space bar to continue

Set the Fluke 5520A to output 10.0000 V, and press the space bar. After a short while, the following calibration constants and prompt are displayed on the PC:

diff = (Counts - Offset)

3032676 = 3032636 - -40

Volts per count = 0.000003

- press space bar to continue

Press the space bar to return to the Calibration Menu.

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Cal Volts Output

Connect the UUT as shown in Figure 14.

Figure 14. Volts Output Calibration Connections

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From the Calibration Menu, type the number or letter for Cal Volts Output. The PC displays:

Zero into DAC. Enter the Volts displayed :

Set the Fluke 8508A to read V DC. When the reading on the 8508A has stabilized, enter the value in volts on the PC, and press Enter. You only need to enter four places past the decimal point and do not need to enter the units (V). After a short while, the PC displays:

Max value into DAC. Enter the Volts displayed :

Enter the voltage reading (four places past the decimal) from the Fluke 8508A on the PC, then press Enter. After a short while the PC displays the following calibration constants and new prompt:

0.000170 = 11.071999 - 0.000000 )/ 65279.00

- press space bar to continue

Press the space bar to return to the Calibration Menu.

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Calibrators

Calibration Adjustment

Cal mA Input (Fluke 725 Only)

Connect the UUT as shown in Figure 15.

Figure 15. mA Input Calibration Connections

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From the Calibration Menu, type the cal step for Cal mA Input. The PC displays:

Enter 0 ma - press space bar to continue

Set the Fluke 5520A to output 0.000 mA, let the reading settle a few seconds, then press the space bar on the PC. After a short while, the PC displays the following calibration constant and new prompt:

Offset = -337

Enter 24.00 ma - press space bar to continue

Set the Fluke 5520A to output 24.000 mA, let the reading settle a few seconds, then press the space bar on the PC. After a short while, the UUT displays the following calibration constants and new prompt:

diff = (Counts - Offset)

8106924 = 8106587 - -337

mA per count = 0.000003

press space bar to continue

Press the space bar to return to the Calibration Menu.

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Calibration Manual

Cal mA Output (725 Only)

Connect the UUT as shown in Figure 16.

Figure 16. mA Output Calibration Connections

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From the Calibration Menu, enter the cal step for Cal mA Output. The PC displays:

Zero into DAC. Enter mA displayed :

Set the Fluke 8508A to read DC current. When the reading on the Fluke 8508A has stabilized, enter the value in milliamps on the PC, then press Enter. You only need to enter four places past the decimal point and do not need to enter the units (mA). Wait for the following prompt on the PC:

Max value into DAC. Enter mA value displayed :

Enter the current reading from the Fluke 8508A in the PC, then press Enter. After a short while, the following calibration constants and new prompt are displayed on the PC:

-1.628906 = ( 24.735999 - 0.076400 )/ 65279.00

mA per count = -1.628906

- press space bar to continue

Press the space bar to return to the Calibration Menu.

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Calibrators

Calibration Adjustment

Cal mV Input

Connect the UUT as shown in Figure 17.

Figure 17. mV Input Calibration Connections

aal04.eps

From the Calibration Menu, type the number or letter for Cal mV Input. The PC displays:

Enter 0 mV - press space bar to continue

Set the Fluke 5520A to output 0.000 mV, let the output settle then press the space bar on the PC. After a short while, the PC displays the following calibration constant and new prompt:

Offset = -714

Enter 90.00 mV - press space bar to continue

Set the Fluke 5520A to output 90.000 mV, let the output settle, then press the space bar on the PC. After a short while, the PC displays the following calibration constants and new prompt:

diff = (Counts - Offset)

7513104 = 7512390 - -714

mV per count = 0.000012

-press space bar to continue

Press the space bar to return to the Calibration Menu.

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Calibration Manual

Cal mV Output

Connect the UUT as shown in Figure 18.

Figure 18. mV Output Calibration Connections

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From the Calibration Menu, enter the cal step for Cal mV Output. The PC displays:

Zero into DAC. Enter mV displayed :

Set the Fluke 8508A to read V DC. When the reading on the Fluke 8508A has stabilized, enter the value in millivolts on the PC, then press Enter. You only need to enter four places past the decimal point and do not need to enter the units (mV). After a short while, the PC displays:

Max value into DAC. Enter mV value displayed :

Enter the mV reading from the Fluke 8508A on the PC, press Enter, then press the space bar. After a short while, the PC displays the following calibration constants and new prompt:

6537.086487 = 111.874998 - -12.450000 )/ 65279.00 mV per count = 6537.0864

- press space bar to continue

Press the space bar to return to the Calibration Menu.

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Calibrators

Calibration Adjustment

Cal Thermocouples

Connect the UUT as shown in Figure 19.

Figure 19. Thermocouples Calibration Connections

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From the Calibration Menu, enter the cal step for Cal Thermocouples. The PC displays:

Connect accurate T/C source : TYPE-J thermocouple

Simulate 0.0 degrees C

- press space bar to continue

Set the Fluke 5520A to output 0.00 degrees C for a type-J thermocouple using the ITS-90 standard, then press the space bar on the PC. After a short while, the PC displays the following calibration constant and new prompt:

CJC Temp Read = 27.359071

Type 2

CJC mV = 1.400393

mV Read = -1.260579

CJC = 0.139814, (cjc - type_j) = 2.736758

- press space bar to continue

Press the space bar to return to the Calibration Menu.

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Calibration Manual

Cal Ohms Hi Source

Connect the UUT as shown in Figure 20.

Figure 20. Ohms Hi Source Calibration Connections

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From the Calibration Menu, enter the cal step for Cal Ohms Hi Source. The PC displays:

2500 into DAC. Enter Ohms displayed :

Set the Fluke 8508A to read 4-terminal Ohms. When the reading on the Fluke 8508A has stabilized, enter the value in Ohms on the PC, then press Enter. After a short while, the PC displays:

Max value into DAC. Enter Ohms value displayed :

Enter the resistance reading from the Fluke 8508A in the PC, then press Enter. After a short while, the PC displays the following calibration constants and new prompt:

0.050685 = 3309.000015 - 0.365000 )/ 65279.00 Ohms per count = 0.050685

- press space bar to continue

Press the space bar to return to the Calibration Menu.

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Calibrators

Calibration Adjustment

Cal Ohms Low Source

The UUT connection is the same as cal Ohms Hi Source, it is shown in Figure 20.

From the Calibration Menu, enter the cal step for Cal Ohms Low Source. The PC displays:

2500 into DAC. Enter Ohms displayed :

Set the Fluke 8508A to read 4 terminal Ohms. When the reading on the Fluke 8508A has stabilized, enter the value in Ohms on the PC, then press Enter. After a short while, the PC displays:

Max value into DAC. Enter Ohms value displayed :

Enter the resistance reading from the Fluke 8508A in the PC, then press Enter. After a short while, the PC displays the following calibration constants and new prompt:

Gain = 0.006910

y intercept = -57

= 451.459980 - 17.670000 )/ 65279.00 - press space bar to continue

Pressing the space bar will return to the Calibration menu.

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Calibration Manual

Cal RTD Low Range

Connect the UUT as shown in Figure 21.

Figure 21. RTD Low Range Calibration Connections

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From the Calibration Menu, enter the cal step for Cal RTD Low Range. The PC displays:

Apply 15 ohms to 4 wire jacks

press space bar to continue

Set the Fluke 5520A to output 15.00 Ohms, 2-wire output with 2-wire comp off, then press the space bar on the PC. After a short while, the PC displays:

Apply 350 ohms to 4 wire jacks

press space bar to continue

Set the Fluke 5520A to output 350.00 Ohms then press the space bar on the PC. After a short while, the Calibrator will return to the Calibration Menu.

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Calibrators

Calibration Adjustment

Cal RTD Hi Range

The UUT connection is the same as Cal RTD Low Range, it is shown in Figure 21.

From the Calibration Menu, enter the cal step for Cal RTD Hi Range. The PC displays:

Apply 500 ohms to 4 wire jacks

press space bar to continue

Set the Fluke 5520A to output 500.0 Ohms, 2-wire output with 2-wire comp off, then press the space bar on the PC. After a short while, the PC displays:

Apply 3200 ohms to 4 wire jacks

press space bar to continue

Set the Fluke 5520A to output 3200.0 Ohms, then press the space bar on the PC. After a short while, the Calibrator will return to the Calibration Menu.

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Calibration Manual

Cal ISO Volts

Connect the UUT as shown in Figure 22.

Figure 22. ISO Volts Calibration Connections

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From the Calibration Menu, enter the cal step for Cal ISO Volts. The PC displays:

Enter 0 Volts - press space bar to continue

Set the Fluke 5520A to output 0.0000 V, then press the space bar on the PC. After a short while the PC displays the following a calibration constant and new prompt:

Offset = -324

Enter 30.00 Volts - press space bar to continue

Set the Fluke 5520A to output 30.0000 V, then press the space bar on the PC. After a short while, the PC displays the following calibration constants and prompt:

diff = (Counts - Offset)

30700 = 30376 - -324

Volts per count = 0.000977

- press space bar to continue

Press the space bar to return to the Calibration Menu.

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Calibrators

Calibration Adjustment

Cal ISO mA

Connect the UUT as shown in Figure 23.

Figure 23. ISO mA Calibration Connections

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From the Calibration Menu, enter the cal step for Cal ISO mA. The PC displays:

Enter 0 ma - press space bar to continue

Set the Fluke 5520A to output 0.0000 mA. After a short while, the PC displays the following calibration constants and prompt:

Offset = -323

Enter 24.00 ma - press space bar to continue

Set the Fluke 5520A to output 24.0000 mA then press the space bar on the PC. After a short while, the PC displays the following calibration constants:

diff = (Counts - Offset)

32133 = 31810 - -323

mA per count = 0.000747

- press space bar to continue

Press the space bar to return to the Calibration Menu.

Adjustment is completed. Turn the UUT off, then back on, to return to normal operation.

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Calibration Manual

Calibration Adjustment Procedures (726)

Initiating Communication

Note

This procedure does not cover the verification of the unit. The Calibrator should never use up more than 50 % of its specifications immediately after calibration. When calibrating the 726, you can also exit and enter calibration mode while performing the verification, subject to the dependencies listed in the procedure.

To initiate calibration-mode communication, use the terminal to send the CAL_START command. Enter the required password “627”. The calibration menu (below) is then displayed on the terminal.

726 Calibration Menu

Calibration Menu

1: ISO mA Input 2: ISO Volts Input 3: mA Input 4: mA Output 5: Volts Input 6: Volts Output 7: Low Ohms Source 8: High Ohms Source 9: Ohms Measure 10: TC mV Output 11: TC mV Input 12: TC CJC 13: Exit

Enter Selection:

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Calibrators

Calibration Adjustment

Calibrating Isolated mA Input

Connect the UUT as shown in Figure 24.

Figure 24. Isolated mA Input Calibration Connections

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After the proper connections have been made, type “1” (the first calibration step) then press the Enter key on the PC keyboard. Input directions are displayed at the bottom of the calibration menu:

Enter Selection:

Input 0 mA, Press Enter When Stable

Input 24 mA, Press Enter When Stable

Use the 5520A to input 0 mA and then 24 mA.

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Calibrating Isolated Voltage Input

Connect the UUT as shown in Figure 25.

Figure 25. Isolated Voltage Input Calibration Connections

After making the proper connections, type “2” then press the Enter key on the PC keyboard. Input directions are displayed at the bottom of the calibration menu:

Enter Selection:

Input 0 Volts, Press Enter When Stable

Input 30 Volts, Press Enter When Stable

Use the 5520A to input 0 V and then 30 V.

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Calibrators

Calibration Adjustment

Calibrating mA Input

Connect the UUT as shown in Figure 26.

Figure 26. mA Input Calibration Connections

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After making the proper connections, type “3” then press the Enter key on the PC keyboard. Input directions are displayed at the bottom of the calibration menu:

Enter Selection:

Input 0 mA, Press Enter When Stable

Input 24 mA, Press Enter When Stable

Use the 5520A to input 0 mA and then 24 mA.

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Calibrating mA Output

Connect the UUT as shown in Figure 27.

Figure 27. mA Output Calibration Connections

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After making the proper connections, type “4” then press the Enter key on the PC keyboard. Input directions are displayed at the bottom of the calibration menu:

Enter Selection:

First Calibration Point. Enter mA displayed:

Second Calibration Point. Enter mA displayed:

Use the 8508A to measure the two calibration points. Enter each of the two calibration points as prompted.

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Calibrators

Calibration Adjustment

Calibrating Voltage Input

Connect the UUT as shown in Figure 28.

Figure 28. Voltage Input Calibration Connections

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After making the proper connections, type “5” then press the Enter key on the PC keyboard. Input directions are displayed at the bottom of the calibration menu:

Enter Selection:

Input 0 Volts, Press Enter When Stable

Input 20 Volts, Press Enter When Stable

Use the 5520A to input 0 V and then 20 V.

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Calibration Manual

Calibrating Voltage Output

Connect the UUT as shown in Figure 29.

Figure 29. Voltage Output Calibration Connections

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After making the proper connections, type “6” then press the Enter key on the PC keyboard. Input directions are displayed at the bottom of the calibration menu:

Enter Selection:

First Calibration Point. Enter Volts displayed:

Second Calibration Point. Enter Volts displayed:

Use the 8508A to measure the two calibration points. Enter each of the two calibration points as prompted.

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Calibrators

Calibration Adjustment

Calibrating Low Ohms Source

Connect the UUT as shown in Figure 30.

Figure 30. Low Ohms Source Calibration Connections

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After making the proper connections, type “7” then press the Enter key on the PC keyboard. Input directions are displayed at the bottom of the calibration menu:

Enter Selection:

First Calibration Point. Enter Ohms displayed:

Second Calibration Point. Enter Ohms displayed:

The 8508A should be locked in the 2 kΩ range (1.0 mA excitation). Enter each of the two calibration points as prompted.

Note

For best accuracy at:

15 Ohms: Use 8508A 200

360 Ohms: Use 8508A 2 k

Ω

range, 4-wire, LOI On

Ω

range, 4-wire, LOI Off

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Calibration Manual

Calibrating High Ohms Source

Connect the UUT as shown in Figure 31.

Figure 31. High Ohms Source Calibration Connections

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After making the proper connections, type “8” then press the Enter key on the PC keyboard. Input directions are displayed at the bottom of the calibration menu:

Enter Selection:

First Calibration Point. Enter Ohms displayed:

Second Calibration Point. Enter Ohms displayed

The 8508A should be locked in the 20 kΩ range (0.1 mA excitation). Enter each of the two calibration points as prompted.

Note

For best accuracy set to:

1500 Ohms: Use 8508A 2 k

3200 Ohms: Use 8508A 20 k

Ω

range, 4-wire, LOI On

Ω

range, 4-wire, LOI Off

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Calibrators

Calibration Adjustment

Calibrating Ohms Measure

Connect the UUT as shown in Figure 32.

Figure 32. Ohms Measure Calibration Connections

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After making the proper connections, type “9” then press the Enter key on the PC keyboard. Input directions are displayed at the bottom of the calibration menu:

Enter Selection:

Input 15 Ohms, Press Enter When Stable

Input 400 Ohms, Press Enter When Stable

Input 4000 Ohms, Press Enter When Stable

Use the 5520A to input 15 Ω, 400 Ω, and finally 4000 Ω. The Enter key must be applied prior to advancing between steps.

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Calibrating Thermocouple mV Output

Connect the UUT as shown in Figure 33.

Figure 33. Thermocouple mV Output Calibration Connections

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After making the proper connections, type “10” then press the Enter key on the PC keyboard. Input directions are displayed at the bottom of the calibration menu:

Enter Selection:

First Calibration Point. Enter mV displayed:

Second Calibration Point. Enter mV displayed:

Use the 8508A to measure the two calibration points. Enter each of the two calibration points as prompted.

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Calibrators

Calibration Adjustment

Calibrating Thermocouple mV Input

Connect the UUT as shown in Figure 34.

Figure 34. Thermocouple mV Input Calibration Connections

After making the proper connections, type “11” then press the Enter key on the PC keyboard. Input directions are displayed at the bottom of the calibration menu:

Enter Selection:

Input –10mV, Press Enter When Stable

Input 90mV, Press Enter When Stable

Use the 5520A to input –10 mV and then 90 mV.

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Calibrating Thermocouple CJC:

Connect the UUT as shown in Figure 35. For the lag bath setup, see Figure 36.

Figure 35. Thermocouple CJC Calibration Connections

aal11f.eps

The calibration of the TC CJC (Cold Junction Compensation) is a critical part of the calibration process, it is important that the thermocouple junction be allowed to completely stabilize. Usually this takes a minimum of five minutes.

After the proper connections have been made, type “12” then press the Enter key on the PC keyboard. Use a lag bath to source a stable temperature the 726. Enter the value of the temperature and the main calibration menu will reappear. The temperature scale used is ITS-90.

Page 75

Calibrators

Replaceable Parts

When servicing this Calibrator, use only the replacement parts specified. Userreplaceable parts are listed in Table 19 and shown in Figure 36.

Table 19. Replacement Parts

Item Description Fluke No. Quantity

E F G H

J K L

724-725 Case top 726 Case top

724 LCD mask 725 LCD mask 726 LCD mask

Elastomeric strips 802063 2

724 Input/output bracket 725 - 726 Input/output bracket

LCD bracket 658390 1

Mounting screws 494641 11

Backlight 690336 1

724 - 725 LCD 690963 1

724 Keypad 725 Keypad 726 Keypad

Case bottom 664235 1

AA alkaline batteries 376756 4

Case screws 832246 4

664232

2491880

1548383

664273

2491914

1549921

691391

1548126

690955

2461532

N O P Q R

Battery door 664250 1

Accessory mount 658424 1

Tilt stand 659026 1

Battery door 1/4-turn fasteners 948609 2

TL75 series test leads 855742 1

Test lead, red Test lead, black

AC70A alligator clip, red AC70A alligator clip, black

724 Case top decal 725 Case top decal 726 Case top decal

688051 688066

738047 738120

1548329

690948

2530988

1 1

Page 76

724/725/726

Calibration Manual

Item Description Fluke No. Quantity

Table 19. Replacement Parts (cont.)

Not

Shown

724 Product Overview Manual 1547851 1 725 Product Overview Manual 1549644 1

726 Product Overview Manual 2441588 1

724 CD-ROM (contains Users Manual) 1547849 1 725/726 CD-ROM (contains Users

1549615 1

Manual) 700SC serial interface cable 667425 Optional

accessory

aal02f.eps

Figure 36. Replacement Parts

Page 77

Manual Supplement

Manual Title: 725 Users Supplement Issue: 3 Print Date: October 1998 Issue Date: 3/08 Revision/Date: 3, 5/04 Page Count: 2

This supplement contains information necessary to ensure the accuracy of the above manual. This manual is distributed as an electronic manual on the following CD-ROM:

CD Title: 725/726 Product Manuals CD Rev. & Date: 4, 9/2005 CD PN: 1549615

Page 78

725 Users Manual Supplement

Change #1

On page 59, under RTD Excitation (simulation) change the following:

From:

PT 200-385 0.15 to 3.0 ma

To:

PT 200-385 0.05 to 0.80 mA

Under Temperature, RT Ranges, and Accuracies (ITS-90) replace the Allowable excitation current (source) with the following:

Ni120, Pt100-385, Pt100-392, Pt100-JIS: 0.15 to 3.0 mA Pt200-385, Pt500-385: 0.05 to 0.80 mA; Pt1000-385: 0.05 to 0.40 mA

12/04 1

Page 79

725 Users Manual Supplement

Change #2, 40767

On page 60, under General Specifications, add the following:

Battery life Battery life under load value

Protection Class Pollution Degree II

25 hours typical 12 mA in 500 Ω = 12 hrs

Change #3

On page 3, Table 1, add the following:

;

2 3/08

Conforms to Australian C-Tick directives

Fluke 726 Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

LIMITED WARRANTY AND LIMITATION OF LIABILITY

Table of Contents

List of Tables

List of Figures

Introduction

Contacting Fluke

International Symbols

Specifications

DC Voltage Measurement (724 and 725)

DC Voltage Measurement and Source (726)

DC Voltage Source (724 and 725)

DC mA Measurement and Source (724 and 725) (Measurement only for 724)

DC mA Measurement and Source (726)

Ohms Measurement (724 and 725)

Ohms Measurement (726)

Ohms Source (724 and 725)

Ohms Source (726)

Frequency Measurement (725)

Frequency Measurement (726)

Frequency Source (725)

Frequency Source (726)

Millivolt Measurement and Source (724 and 725)

Temperature, Thermocouples (724 and 725)

Temperature, Thermocouples (726)

Temperature, RTD Ranges, and Accuracies (724 and 725)

RTD Accuracy (Read and Source) (ITS-90) (726)

Loop Power Supply

Pressure Measurement (725 and 726)

Pulse Read and Pulse Source (726)

Pressure Units Availability (725)

General Specifications

Cleaning the Calibrator

Replacing the Batteries

Fuses

Remote Control Interface (725 and 726)

Serial Command List (726)

Required Equipment

Performance Tests

Preparing for the Performance Tests

Upper Display Voltage Measurement Tests

Lower Display mV/TC Measurement Tests

Lower Display Voltage Measurement Tests

Upper Display mA Measurement Tests

Lower Display mA Measurement Tests (725 and 726)

Lower Display Frequency Measurement Test (725 and 726)

Lower Display Frequency Source Test (725 and 726)

Lower Display 4-Wire Resistance Measurement Tests

Lower Display 3-Wire RTD Measurement

Lower Display Thermocouple Measurement Tests

Lower Display Thermocouple Source Test

Lower Display mA Source Tests (725 and 726)

Lower Display mV Source Tests

Lower Display Voltage Source Tests

Lower Display Ohms Source Tests

Pressure Module Input (725/726)

Calibration Adjustment

Setup

Initiating Communication (724 and 725)

Calibration Adjustment Procedures (724 and 725)

Cal Volts Input

Cal Volts Output

Cal mA Input (Fluke 725 Only)

Cal mA Output (725 Only)

Cal mV Input

Cal mV Output

Cal Thermocouples

Cal Ohms Hi Source

Cal Ohms Low Source

Cal RTD Low Range

Cal RTD Hi Range

Cal ISO Volts

Cal ISO mA

Calibration Adjustment Procedures (726)

Initiating Communication

Calibrating Isolated mA Input

Calibrating Isolated Voltage Input