Keithley 7035, Инструкция по эксплуатации

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Service Information
5-6
Contact potential tests
These tests check the EMF generated by each relay contact
pair (H and L) for each pathway. The tests simply consist of
using a sensitive digital voltmeter (Model 182) to measure
the contact potential (Figure 5-3).
Perform the following procedure to check the contact poten-
tial of each path:
1. Turn off the Model 7001/7002 mainframe if it is on.
2. Place jumpers between banks A-B, B-C, C-D, D-E, E-F,
F-G, G-H, and H-I.
3. Turn on the Model 182 and allow the unit to warm up to
achieve rated accuracy.
4. Place a short between HI to LO on each input (channels
1-36).
5. Place a short between HI to LO on output bank I (long
enough to cut with wire cutters).
6. Connect the Model 182 input leads to HI and LO output
bank A using copper wires.
7. Install the Model 7035 in the Model 7001/7002 slot 1
and turn on the mainframe.
8. Allow Models 7001/7002, 7035, and 182 to warm up for
two hours.
9. Select the 3mV range on the Model 182.
10. Press REL READING (on the Model 182) to null out
internal offsets. Leave REL READING enabled for the
entire procedure.
11. Turn off the mainframe. Remove the Model 7035 from
slot 1. Cut the short on bank I output HI to LO.
12. Install the Model 7035 in mainframe slot 1, and turn on
power.
13. Wait 15 minutes.
14. Program the mainframe to close channel 1!1.
15. After settling, verify that reading on the Model 182 is
<1
µ
V.
16. From the mainframe, open channel 1!1.
17. Repeat steps 14 through 16 for all 36 channels.