What is the role of a relay in electrical applications?

A relay serves as an electromechanical switch that allows a low-power signal to control a high-power circuit. This is especially important in applications where safety and efficiency are paramount. By using a small input signal to activate the relay, which in turn can switch a larger load on or off, the design of electrical systems can be significantly simplified.

For instance, in a situation where a microcontroller operates at a low voltage and current, it would not be sufficient to power a high-voltage device directly. Instead, a relay can effectively separate the control circuit from the high-power circuit, protecting sensitive components and allowing one to influence the other without direct electrical contact.

This functionality is essential in many applications, such as automotive systems, home appliances, and industrial machinery, where relays act as intermediaries that manage power levels efficiently and safely.