Normally Closed
Contacts 1. Hardware Connections
Figure 2-3. Closed-Channel Resistance (NC Channels)
2.Equipment Setup
•Set DMM to:
•Send *RST to the switch.
•Send CLOS (@100:115) to the switch to open all NC contacts.
3.
•Send OPEN (@100) to the switch to close channel 00.
•Trigger the DMM and record the reading.
4.
•Send CLOS (@100) to the switch to open channel 00.
•Trigger the DMM and verify that an open circuit is indicated (>108 Ω).
5.Closed- and
•Repeat steps 3 and 4 for channels 01 through 15. Use
CLOS (@ccnn) and OPEN (@ccnn), where
cc= switch card number
24 Verification Tests | Chapter 2 |