what are applications of shunt release in circuit breaker

what are applications of shunt release in circuit breaker.

     A shunt trip device is an optional accessory in a circuit breaker that mechanically trips the breaker when power is applied to the shunt trip terminals. The power for the shunt trip does not come from within the breaker, so it must be supplied from an external source

Shunt trip circuit diagram.

shunt trip coil

     A shunt-trip coil is a built-in component of a shunt-trip circuit breaker. It is a magnetic coil that can be energized externally to make the breaker trip to shut off the flow of current. 

What are the application of Under voltage release

 What are the application of Under voltage release

Under voltage release 

        Under voltage release provides tripping the circuit breaker if the input voltage (phase or line) drops below 70% of the rated value. Also, it prevents the circuit breaker from closure if the voltage is below 85% of the rated value. The main purpose of the under voltage release is to de-energize electric equipment in case of impermissible reduction of voltage. Also, the release can be used as shunt release if a push button (NC) is connected in series with the circuit controlling the release. On short opening of the push-button contacts the release will trip the circuit breaker. 

Under voltage relay 

   A relay that has contacts that operate when the voltage drops below a set voltage. Under voltage relays are used for protection against voltage drops, to detect short-circuit faults,and more.

Under voltage coil 

• An Under Voltage coil is used to remotely trip a circuit breaker and some switch dis connectors.
• An Under Voltage coil has to have a voltage applied to it to enable the device to close, and have the supply removed from it to trip the device.
• An example of an application for an Under Voltage coil would be for emergency stop or load shedding.