SWITCH/SWITCHED CONTACTS RESISTANCE MEASUREMENT PROCEDURES
|NOTE: Steps 5 and 6 test switches and contactor/relay contacts using the|
resistance (continuity) check method.
5. Turn power off, then discharge all capacitors in the circuit. Disconnect at least
one lead of the switch or contacts from the circuit.
|Power is off in preparation for the resistance measurement.|
|6. Set up the VOM/DMM to measure resistance. If using a VOM, select the R x 1|
Connect the VOM/DMM across the switch or contacts as shown in Figure
SP-8-8. Measure the resistance.
|If the VOM/DMM shows an infinite resistance reading, the switch/switched
contacts are open.
If the VOM/DMM shows a short (zero resistance) reading, the switch/switched
contacts are closed.
If the VOM/DMM shows a measurable resistance, the switch contacts are neither
fully open or closed or some other problem exists. This condition is not permitted
and the device should be replaced.
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