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Documenting Process Calibrator Performance Verification Tests 25 Table 13. Temperature Meas ure Verification Input dcmV (referenced to 0 °C) Minimum 1-Year °C Maximum 1-Year °C Minimum 2-Year °C Maximum 2-Year °C -5.550 …

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Calibration Manual

5522A

CALIBRATOR

Fluke 75X

Room Temperature

Lab Bath

Fluke 1551A Ex

Thermometer

Fluke 5522A

TYPE-K

Thermocouple

Wire

CuCu

gso12.eps

Figure 10. Temperature Measure (TC) Verification Connections

Documenting Process Calibrator

Performance Verification Tests

Table 13. Temperature Measure Verification

Input dcmV (referenced to 0 °C)

Minimum

1-Year °C

Maximum

1-Year °C

Minimum

2-Year °C

Maximum

2-Year °C

-5.550 mV (-180 °C) -180.9 -179.1 -181.2 -178.8

0.000 mV (0 °C) -0.5 0.5 -0.6 0.6

52.410 mV (1300 °C) 1299.1 1300.9 1298.8 1301.2

Lag Bath Reference Table, Type K, ITS-90

Tem

. °C 18 19 20 21 22 23 24 25 26 27 28

mV 0.718 0.758 0.798 0.838 0.879 0.919 0.960 1.000 1.041 1.081 1.122

Thermocouple Source

To verify the thermocouple source function:

Note

This test uses a Type-K thermocouple setting on the UUT.

1. Use Type-K thermocouple wire and copper wire to connect the 8508A to the

UUT -TC jack as shown in Figure 10 (the 8508A is used in place of the 5522A).

The type K-to-copper junctions must be welded or made with tight screw

terminals and submersed in the lag bath (room temperature). Use the standard

thermometer (0.1 % accuracy) to measure the temperature of the lag bath.

2. Set the UUT to the thermocouple source function, linear mode, TC type K, ITS-

90 scale, internal reference, and °C.

3. Set the 8508A to measure mV dc.

4. Stop for a minimum of 1 minute for thermal “emfs” (caused by insertion of the

connectors) to dissipate, and let the lag bath become stable for a minimum of 15

minutes.

5. Source each of the temperatures in Table 14 from the UUT. At each point,

correct the DMM measured voltage. To do this, add the millivolt equivalent of

the Type-K junction at the lag bath temperature (use the Type-K ITS-90 chart).

6. Continue through the test points. See if the value shown on the UUT is in the

range shown in the applicable column in Table 14.

7. When you complete the test, push  on the UUT two times to turn the source

function off. This conserves battery life.

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Calibration Manual

Table 14. Temperature Source Verification (Type-K Thermocouple, ITS-90)

UUT

Output

Nominal DC mV

Minimum

1-Year

Maximum

1-Year

Minimum

2-Year

Maximum

2-Year

-180 °C -5.5504 -5.5616 -5.539 -5.5653 -5.5353

0 °C 0.0000 -0.0197 0.0197 -0.0237 0.0237

1300 °C 52.4103 52.3928 52.4277 52.3893 52.4312

RTD Measure, Four-Wire

Note

It is necessary to use a separate verification procedure for the three-wire

RTD measure function because it uses different circuits. The two-wire RTD

measure circuit is tested during the Ohms Measure procedure. If a 5522A is

not available, replace it with a variable resistance source such as a general

resistance RTD-100 RTD simulator and a DMM to measure the variable

resistance source for accuracy. Use the resistance equivalents shown in

Table 15.

To verify the four-wire RTD Measure function:

1. Connect the UUT to the 5522A as shown in Figure 11. Use a four-wire

connection and four-wire compensation.

2. Set the UUT to the RTD measure function, Pt100 (385), ITS-90 scale, and four-

wire termination.

3. Set the 5522A to RTD, Pt100 (385) at -180 °C, ITS-90 scale, and comp four-

wire.

4. Set the 5522A to [Operate].

5. See if the value shown on the UUT is in the range shown in the applicable

column in Table 15.

6. Continue through the test points.

7. When you complete the test, set the 5522A to STANDBY.