Solid State Relays (SSRs) offer several advantages over electromechanical relays such as no moving parts, higher switching speed, improved reliability from the lack of physical wear-out, smaller footprints, and lower cost. The solid-state isolator is integral to the SSR, providing safe control of the drive elements.

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A solid state relay (SSR) is an electronic switching element;  in which a larger current or voltage can be controlled with a control signal.  The function of SSR is similar to electromechanical relays.🎭