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voltage free contacts

voltage free contacts

voltage free contacts

(OP)
Would anyone be kind enough to explain to me how a voltage free contact actually works?

Luke.

RE: voltage free contacts

A voltage-free contact is any kind of switching circuit that is isolated, does not introduce any potential into the user circuit, and is not referred to ground or a supply rail. This allows the user to connect it to any circuit potential of choice, within reason.

The most obvious example is a pair of relay contacts, which are truly volt-free. A common sort of output is the open-collector transistor stage. This is not volt-free since its base and emitter are referenced to the driver circuit and one supply rail, usually ground. Opto-isolators are arguably semi volt-free as they provide high voltage isolation between input and output, but the floating transistor can only drive certain kinds of other circuits and not an a.c.load directly.

RE: voltage free contacts

hi...
if you use a meter whether in AC or DC scale these contact has no potential at all with respect to ground or any part of a circuit ... but this contact is still being actuated by an electromagnet..

another word use in industry for this is "dry contact"..

dydt

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