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Voltage drop across safety prox switches
2

Voltage drop across safety prox switches

Voltage drop across safety prox switches

(OP)
Hello, I'm trying to use 6 proximity switches in series to energize a solid state relay for a safety circuit. Using 120vac going through the prox switches, my voltage drops down to about 83 volts. My relay requires 90 so I'm chattering my relay and contactor. Any suggestions to cure this would be greatly appreciated. Thanks

RE: Voltage drop across safety prox switches

Bigger wire.

RE: Voltage drop across safety prox switches

This is generally a bad idea.  These prox switches require a small current to operate.  When they are operated in series, each switch does not have enough voltage to function properly. Hope you have enough money in your budget to do it right.

RE: Voltage drop across safety prox switches

I agree with OperaHouse. I would change the circuit so that no proximity switches were in series, or go to a non powered type of proximity switch such as a magnetic reed switch. I have seen magnetic reed switches used succesfully in series in intruder alarm systems. For line powered proximity switches use a relay for each one or look for a switch with the power connections independant of the switching connections.
respectfully

RE: Voltage drop across safety prox switches

I must assume that you do not have a SLC or PLC in your safety circuit design scheme or this question would not have been asked. Where I work at and repair electrical equipment we have more prox switches than carter has pills and in no case do I ever see prox switches connected in series. If you could give us an idea of what the circuit is protecting then we could most probably provide you with a viable solution.

RE: Voltage drop across safety prox switches

You could turn a relay on with each prox.and have the contacts of the relay in series, that way you would have full Voltage at the end. If you wanted to wire a dummy light in Parrallel with the relay coil and this would give you quick referance to what proxes are not making.

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