A solid state relay SSR is an electrical switch that can be used to turn things on and off using another electrical input unlike electromechanical relays the ssr uses semiconductor switches and optoelectronics instead of magnetism and moving contacts.
what is selector switch
selector switch can control on or off of different currents circuit by rotating the handle common used for control consisting of a mechanical or electrical or electronic device for making or breaking or changing the connections in a circuit.

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