CIRCUIT BREAKER WITH MOVING MAGNETIC CORE FOR LOW CURRENT MAGNETIC TRIP

A circuit breaker (1) is disclosed having a movable magnetic core (101) provided in the magnetic trip assembly (23) thereof adapted to lower the current levels at which the magnetic trip mechanism will operate. The magnetic trip assembly also includes a pivotally connected armature (103), a current carrying conductor (107), a fixed magnetic yoke (100) and a latchable operating mechanism (21). A primary air gap (91) exists between the armature and the fixed yoke (100). The movable core (101) is designed to move into an extended position which reduces the primary air gap (G1) which in turn increases magnetic flux coupling which allows the magnetic force required for the armature (103) to pivotally rotate to unlatch tne operating mechanism (21) and thereby trip the circuit breaker to be generated at a lower current level. This reduction in current is the desired effect of the new design.