A relay is a switch that can be electronically controlled to open or close a circuit.
Generally speaking, relays consist of an electromagnet, a mechanically movable contact, switching points, and a spring. An electrical signal is then used to activate the electromagnet which opens or closes the circuit; when the signal is turned off the electromagnet deactivates and the spring returns the circuit to its original position.
Deeper Knowledge on Relays
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Broader Topics Related to Relays
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