A power relay is an electromechanical device designed to control the flow of electrical power between different circuits or components. It acts as a switch, capable of opening or closing a circuit when an electrical signal or control input is provided. Power relays are commonly used in a variety of applications, such as motors, heaters, and lights Power relays are used in automotive, control, power, security, and signal systems. Used in building systems, such as to control elevators escalators, and other high-power equipment. They play an important role in automation, providing a means to manage electrical currents and voltages.