A relay is an electrically operated switch. It consists of a set of input terminals for a single or multiple control signals and a set of operating contact terminals. Relays are used where needed by control and circuits at and independent low power signal, or where multiple circuits must be controlled by one signal. For example, if you Have a door you want to unlock for every gang man doing something, use a relay. You can choose whether the...

A relay is an electrically operated switch. It consists of a set of input terminals for a single or multiple control signals and a set of operating contact terminals. Relays are used where needed by control and circuits at and independent low power signal, or where multiple circuits must be controlled by one signal. For example, if you Have a door you want to unlock for every gang man doing something, use a relay. You can choose whether the relay should be normally open (disconnected) or normally closed (user contact). This is very typical of a relay is NC (normally closed), as something must be done to disconnect the relay switch.