(Optional)
34903A Relay Contact Resistance Verification
1 Be sure to read “Plug-in Module Test Considerations” on page 87.
2 Install the 34903A module in slot 100. Close Channels 01 through 20.
Remove the module from the 34970A.
3 Measure the resistance from the CM terminal to the NO terminal on
each channel.
4 Install the module in slot 100. Open Channel 01 through 20.
Remove the module from the 34970A.
5 Measure the resistance from the CM terminal to the NC terminal on
each channel.
Note: In general, a new relay should have a contact resistance of less than
0.2Ω. Relays with contact resistance in excess of 1.2Ω should be replaced.
Module Reference
4
Chapter 4 Calibration Procedures
Relay Verification
101