What do we mean by Electronic Overcurrent Protection ?

Electronic Overcurrent Protection is a form of overcurrent protection which is increasingly used in Low voltage Switchgear.  Electronic overcurrent is used as an alternative to the Thermal Magnetic Trip which uses the Thermal and the magnetic effects of overcurrent to effect a trip in the circuit breaker.

The Electronic overcurrent protection works by sensing the current through the circuit using a current transformer.  The output of the current transformer is fed into an electronic circuit.  

The electronic circuit makes decisions relating to overcurrent response.  Electronic overcurrent protection devices have a transistor through which the load current flows.  In an overcurrent scenario, they are able to quickly switch off the transistor and interrupt the fault current.  

This helps in preventing a general undervoltage of the system and very fast response in isolating the fault.