Solid-state Relays (SSRs)
A solid-state relay (SSR) is an electronic switching device that switches on or off when an external voltage (AC or DC) is applied to its control terminals. With no moving parts, solid-state relays have a greatly improved life expectancy compared to electromechanical relays. Additionally, SSRs have faster switching speeds than electromechanical relays and have no physical contacts to wear out. The solid-state relay consists of a sensor that responds to the appropriate input (control signal), an electronic switching device that switches power to the load circuit, and a coupling mechanism that enables the control signal to activate this switch without the need for mechanical parts.