Originally Posted by
cheetahcnc
I have used the P&F (and other brands) two wire prox switches. If you test it with the lowest voltage first and work your way up, you should be OK as I have experimented like this previously. Note: the switches are offered normally closed, and normally open. Have a small relay with coil matching the test voltage, say 5vdc. 5vdc+ to the brown wire, blue wire to one coil wire, the other coil wire to 5vdc-. Test switch with metal. If no action, reverse the blue and brown. Still nothing up the voltage to 12vdc. Make sure the coil on the small load relay matches the test voltage. I usually stop at 120vac, though. Worst case is they still don't work, just like before you started. When I tested a good switch, this method has worked for me. Good luck :drowning:
Jim