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breaking pos or neg for 12vdc coil

breaking pos or neg for 12vdc coil

breaking pos or neg for 12vdc coil

(OP)
diagram for my time clock shows conecting the neg pole from 12 vdc supply to terminal20 and the coil to terminal21.
the other side of coil is connected to the positive side of supply.
at the time I "program" a relay in clock will connect terminal20 and 21 and activate coil which closes contacts on a 110 vac circuit to ring bell.
Problem. The only thing I have access to is two wires coming from the bell that were connected to a switch and the 110 power plug. everything else is sealed. I can not determin if the switch was breaking the pos or neg.
Will this matter if it is the positive or negative running through the relay in my clock.

RE: breaking pos or neg for 12vdc coil

AC has no positive or negative, it's AC. BUT, you must find and open/close the hot side vs. the neutral. This is something that can checked with a DVM.

TTFN
FAQ731-376: Eng-Tips.com Forum Policies

RE: breaking pos or neg for 12vdc coil

(OP)
it is a 12 volt DC coil, closing contacts on 110 ac circuit.

RE: breaking pos or neg for 12vdc coil

(OP)
So sorry for confusion. The question is does anyone know whether or not it could matter if I run the positive through the relay on my time clock, when the drawing shows runing the negative. Again this is because I do not know which I have connected to the switch currently.

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