Maintenance
Performance Tests
7
7-13
RTD Temperature Accuracy TestThe following two RTD Temperature Accuracy Tests are different in that one test uses a
Decade Resistance Source and the other uses an RTD. Only one of the tests need to be
performed to assure operation.
RTD Temperature Accuracy Test (Using Decade Resistance Source)Ensure that Channel 0’s Accuracy Verification Test for DC Volts and 300 Ohm
Resistance Range 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. For Four-terminal performance testing, connect a
second pair of test leads to the H (high) and L (low) terminals of channel 11.
Reinstall the Input Module into the instrument.
3. Connect channel 1’s test leads to the Output HI and LO terminals of the Decade
Resistance Source. For Four-terminal performance testing, also connect channel 11’s
test leads to the Output HI and LO terminals of the Decade Resistance Source.
Connect as shown in Figure 7-3.
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).
4. Switch the instrument ON.
5. Select the Four-terminal RTD temperature function, RTD type PT, for channel 1 on
the Hydra Series II. Press M, select a Decade Resistance value, and ensure the
display reads between the minimum and maximum values shown on Table 7-5.
6. The RTD Temperature Accuracy test is complete. However if you desire to perform
this test on Input Module channels (2 through 10), repeat steps 1 through 5,
substituting the appropriate channel number.
Note
The only type of temperature measurement that can be made on channel 0
is two-terminal RTD. Channels 11 through 20 will support only two-
terminal RTDs.