An electrical auxiliary relay is a type of relay that is used to control and protect various electrical equipment and systems. It is used to perform specific functions, such as controlling the operation of a motor, sensing the presence of voltage, or providing overcurrent protection.
Auxiliary relays are typically connected to other protection devices and control systems within the electrical system and provide additional functionality. They can be connected to contactors, circuit breakers, and other relays to control the operation of the equipment or to provide protection against faults. For example, an auxiliary relay can be used to control the operation of a motor starter by sending a signal to the starter when it is safe to start the motor, or to sense the presence of voltage on a line and send a signal to trip a circuit breaker in the event of an overvoltage condition.
Auxiliary relays can be used in many different electrical systems such as power plants, substations, industrial plants, and buildings. They are used in various applications like motor control, generator protection, transformer protection, protection of feeders, protection of transmission and distribution systems, protection of motors, generators and transformers, protection of feeders, protection of transmission and distribution systems, etc