Performance Verification 3
Keysight DAQ970A/DAQ973A Service Guide 89
DAQM905A relay verification (optional)
This optional procedure uses an external DMM to check that the RF relay is
functioning, using 2-wire ohms measurement with handheld test probes.
1 Be sure to read “Plug-in Module Test Considerations” on page 76.
2 Prepare the module by connecting an SMB short to CH10, CH11, CH12, and
CH13. Connect the COM1 terminal to the DMM.
Be sure to use the correct SMB connectors for the module.
3 Install the module in slot 100.
4 Close Channel 11.
5 Measure the resistance on the DMM. Ensure that measurements is less than
1 . Replace the module if the relay contact resistance is in excess of 1 .
6 Close all othe channels.
7 Measure the resistance, ensure that they are “open” or more than 10 M.
Replace the module if the relay contact resistance if less than 10 M.
8 Repeat steps 4 and 7 for Channels 12, 13, and 14.
9 Repeat steps 2, 3, 4, 5, 6, 7, and 8 for the channels connected to COM2.