What is a shunt-trip circuit-breaker intended for?

Question

What is a shunt-trip circuit-breaker intended for?

Answer 1

To earth a short circuit and prevent harmful currents reaching either people, or sensitive components in the circuit.

Answer 2

A shunt trip breaker is intended to provide the capability to

open the breaker on conditions other than the over-current

profile designed into the breaker.

It's a cheap and handy way to provide remote or emergency shut-downs,

load shedding, etc.

Answer 3

A shunt trip circuit breaker is just a low voltage molded case circuit breaker fitted with an extra trip solenoid to allow external control logic trip the breaker.

The standard molded case circuit breaker does not have any means for an external control or protection system to trip the breaker, other than via the  operator handle.  The shunt trip solenoid plunger pushes activates the mechanical trip release, just like the internal thermal and/or magnetic protection units in the breaker cause it to trip.

The shunt trip circuit breaker DOES NOT connect the circuit to earth to somehow clear a fault.