Monitoring Relays

Monitoring relays are a type of relay that trips a circuit breaker when a fault is detected. Monitoring relays have adjustable operating conditions, whereas normal relays switch according to a fixed threshold. They measure a given parameter, such as voltage , current , temperature or frequency and will trip a circuit breaker when the parameter gets too high or low.

Monitoring relays have a wide range of uses, depending largely on the factor being monitored. For example, they can protect against overcurrent if measuring current, or they can detect an abnormally low frequency if frequency is being measured.

Types of monitoring relay

The main way in which monitoring relays differ is the function that they measure. This can be a number of things, including:

• voltage

• current

• temperature

• frequency