What is the purpose of a relay in electrical systems?

The primary function of a relay in electrical systems is to control a high-power circuit using a low-power signal. A relay is essentially an electromechanical switch that opens or closes based on an electrical signal. By using a small amount of current to activate the relay coil, it can control a much larger current flowing through a different circuit. This is particularly useful in automation and safety applications where a low-power control signal is needed to manage high-power equipment, such as motors or lighting systems. The ability to control larger loads with smaller control signals enhances the efficiency and safety of electrical circuits.

Understanding the role of a relay helps clarify its importance in modern electrical systems, where control and safety are crucial considerations. This functionality is not about altering resistance, reducing voltage, or converting current types, which are associated with other components in electrical engineering.