Fluke 2635A, 2625A service manual Thermocouple Temperature Accuracy Test, Input Module

HYDRA

Service Manual

4.Switch the instrument ON.

5.Select the 4-terminal OHMS function, AUTO range, for channel 1 on Hydra.

6.Set the 5700A to output the resistance values listed in Table 4-2 (Use decades of 1.9).

7.On Hydra press MON and ensure the display reads between the minimum and maximum values (inclusive) shown in Table 4-2.

8.The 4-terminal Resistance Test is complete. However, if you desire to perform this test on other Input Module channels (2 through 10), repeat steps 1 through 7, substituting in the appropriate channel number.

R3

H

L

H

H

L

H

L

H

H

L

H

H

L

L

H

H

L

L

H

H

L

L

H

H

L

L

H

H

L

L

H

H

L

L

H

L

H

L

STRAIN RELIEF

11

12

13

14

15

16

17

18

19

20

H L

H L H L H L H L H L H L H L H L H L

H L

H L H L H L H L H L H L H L H L H L

1

2

3

4

5

6

7

8

9

10

s26f.eps

Figure 4-1. Input Module

4-8. Thermocouple Temperature Accuracy Test

Verify that the Thermocouple Measurement Range Accuracy Test meets minimum acceptable levels before performing this test.

1.Switch OFF power to the instrument and disconnect all high voltage inputs.

2.Remove the Input Module from the rear of the instrument. Open the Input Module, and connect a K-type thermocouple to the H (high) and L (low) terminals of channel 1. (See Table 4-3 for lead colors). Then reinstall the Input Module into the instrument.

4-8