4 Service Information
Checking Defective Relay(s)
N O T E
It is recommended to have the relay(s) checked when it reaches 10 million cycle counts. The relay cycle count can be obtained by using the Agilent Measurement Manager or sending the following SCPI command:
DIAGnostic:RELay:CYCLes? (@<ch_list>)
To check for any defective relay, the equipment required is a digital multimeter with continuity feature.
1Close the particular relay(s). For example: The relay located at Row x Column y.
2By referring to the connector configuration of the DSub connector, connect one of the DMM test leads to pin RxL and another test lead to pin CyL. The DMM should indicate that these two pins are connected or shorted.
3Once this is done, use the same method and perform the same test on pins RxH and CyH. These two pins should be connected or shorted as well.
4Now, open the particular relay(s). Using the same method, check if pins RxL and CyL are disconnected. Perform the same test on pins RxH and CyH as well.
Row 1 
Column 1
Figure 4-4 Defective relay(s) check
44 | U2751A User’s and Service Guide |
