Ice Bath Test - Fluke 51 Service Manual

4. Replace the Dewar Flask cap or cork, and insert the thermocouple wires and Mercury
thermometer as shown in Figure 2. Insert the Mercury thermometer to the same depth
as the thermocouple wire.
Copper wire
5700A
+
Calibrator
-

Ice Bath Test

Use the following procedure to test the thermometer. If the thermometer has two inputs,
this test should be conducted on both thermocouple inputs.
1. If not already selected, select K-type thermocouple on the thermometer using the
D, K, N, and E buttons.
2. Connect the equipment as shown in Figure 2. Allow the setup to thermally stabilize at
least 5 minutes after inserting the thermocouple into the thermometer.
3. Verify that the ice bath temperature reads 0.0
thermometer.
4. Short (or apply 0 mV) to the copper wires at the Calibrator.
5. Verify the thermometer reads 0.0
6. If this test fails, reposition the thermocouple wires and Mercury thermometer to the
same depth in the ice bath, and repeat steps 3-5. If the test continues to fail, perform
the calibration procedure, located after this procedure.
7. Remove the short applied in step 4.
8. Using Table 3, steps 2-5, obtain an output from the Calibrator equal to the values in
the "Input Voltage (mV DC)" column, and verify the thermometer reads within the
limits specified. If any step fails, perform the calibration procedure located later in
this section.
9. Disconnect the thermocouple from the input terminals. This completes the ice bath
test.
K-Type Thermocouple wire
Figure 2. Ice Bath Test Equipment Connections
o
C 0.3
Mercury
Thermometer
- +
51, 52, 53, or 54
Series II
Thermometer
Ice bath
o o
C 0.06 C on the Mercury
o
C.
Thermometer
Performance Tests
K-Type
Thermocouple
connector
- +
zb04f.eps
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