Sofia BauerA 4-pin relay is a type of electrical switch that is used to control the flow of electricity in a circuit. It has four terminals, which are typically labeled as follows:
Terminal 1: Coil terminal 1 Terminal 2: Coil terminal 2 Terminal 3: Normally open (NO) contact Terminal 4: Normally closed (NC) contactWhen the coil of the relay is energized, the contacts will change state.
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