What function does a relay serve in an automation system?

In an automation system, a relay primarily serves as an electrically operated switch. This means it can control a high-power circuit using a low-power signal; thus, it acts as a bridge that enables the automation system to manage and operate various electrical devices. When an electrical current passes through the relay coil, it generates a magnetic field that opens or closes the contacts within the relay, allowing it to turn devices on or off remotely.

This capability is essential in automation because it allows systems to control large motors, lights, or other heavy electrical loads safely without the need for direct human interaction or expensive components. By using a relay, the control system can react to inputs from sensors or software, switching on or off outputs based on predefined conditions. Hence, relays play a critical role in automating processes by ensuring that signals can safely trigger larger mechanical actions.