Describe the operation of solid state relay.

Describe the operation of solid state relay.
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Solidstate relay is electronic equivalent of an electromechanical relay. It consists of controlled power semiconductor switch like triac. There are four terminals. Two are the power terminals for load and two control terminals for applying control signal. Control signal is generally 5V,12V,24V DC. When control signal is applied, the triac is turned ON. When triac is ON, the load is connected to AC supply

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