2635A
Users Manual
7-10
The value returned should now be 90 mV ±0.028 mV (between 89.97 and
90.028 mV).
6. Change Hydra Series II's channel 0 function to the internal 900 mV dc range by
redefining channel 0. Send the following commands:
MON 0 <CR>
FUNC 0,VDC,6 <CR>
Set the 5700A to output 0.9V dc. Send the following commands:
MON 1,0 <CR>
MON_VAL? <CR>
The value returned should be 900 mV ±0.21 mV (899.79 to 900.21mV.)
Four-Terminal Resistance Test
Ensure that Channel 0's Accuracy Verification Test for DC Volts and Resistance meets
minimum acceptable levels.
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 pair of test leads (keep as short as possible) to the H (high) and L
(low) terminals of channel 1, and connect a second pair of test leads to the H and L
terminals of channel 11. Reinstall the Input Module into the instrument.
3. Observing polarity connect channel 1's test leads to the Sense HI and LO terminals
of the 5700A, and connect channel 11's test leads to the Output HI and LO terminals
of the 5700A. Connect as shown in Figure 7-2.
4. Switch the instrument ON.
5. Select the Four-terminal OHMS function, AUTO range, for channel 1 on the Hydra
Series II.
6. Set the 5700A to output the resistance values listed in Table 7-3 (Use decades of
1.9).
7. On Hydra Series II press M and ensure the display reads between the minimum
and maximum values shown on Table 7-3.
8. The Four-terminal Resistance Test is complete. However, if you desire to perform
this test on Input Module channels (2 through 10), repeat steps 1 through 7,
substituting the appropriate channel number.
Note
Four-Terminal connections are made using pairs of channels. Four-
terminal measurements can be made only on channels 1 though 10 (n). The
accompanying pairs are channels 11 through 20 (n+10).
Thermocouple Temperature Accuracy Test
Ensure 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 T-type thermocouple to the H (blue lead) and L (red lead) terminals of
channel 1. Reinstall the Input Module into the instrument.