Monitoring relays are a type of relay that trips a circuit breaker when a fault is detected. A relay is an electrically controlled switch that is used to turn the power on or off in a circuit.
Monitoring relays are more sophisticated than regular relays, as they have adjustable operating conditions, whereas normal relays switch according to a fixed threshold. They measure a given parameter, such as voltage or temperature, and will trip a circuit breaker when the parameter gets too high or low.
What are monitoring relays used for?
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
The factor that you need to measure will decide which monitoring relay you choose.
Description:
Schneider Electric RM17 JC current control relay for
controlling alternating currents in the event of overcurrent. Built-in current transformer with a wide measurement range. Monitors heating and lighting circuits and motor and generator load status. Checks its own power supplyClear ...
Description:
The EMR6 measuring and monitoring relays are designed
for a wide range of switchgear applications. Thanks to their ability to monitor overloads, power fluctuations, phase sequences, machine temperatures and fill levels, the EMR6 relays protect machines and plants and help ...
Description:
Separate relay & LED operation for three phase
monitoring 'V' & thermistor monitoring 'T'The relay monitors the following:Incorrect phase sequence/rotationThreshold voltage 60% of 400VacPhase failure/lossPhase under-voltage (0.6 x 400Vac)Thermistor over-temperatureThermistor open circuitThermistor short ...
Description:
3 Phase Voltage Monitoring Relay with NO/NC Contact
Configuration. Features & BenefitsIncorrect Phase SequencePhase lossPhase undervoltage (0.6 x Un)Adjustable fault delayLED indicationWrite on ID tabDimensions: H78 x W45 x D99mm.
