Relays are essential components in modern electrical and electronic systems, serving as switches that allow circuits to be controlled by low-power signals, or they can isolate different sections of a system. A relay electrical diagram provides a visual representation of how the relay is integrated into a system and how it operates within that system. Understanding this diagram is crucial for anyone involved in circuit design, automation, or electrical engineering.

What is a Relay? At its core, a relay is an electrically operated switch that uses an electromagnet to open or close the contacts in a circuit. Relays are often used to control high-power devices (such as motors, lighting, or heating systems) using a low-power signal. The basic operation of a relay is simple： when an electrical current flows through the relay’s coil, it generates a magnetic field that pulls a metal armature, thereby opening or closing the contacts. There are two main types of relays： Electromechanical relays (EMR)： These relays use a physical moving contact to open or close the circuit.