Extension handle assembly for motor protective circuit breaker and motor protective circuit breaker

An extension handle assembly for a motor protection circuit breaker, wherein the extension handle assembly is installed on the motor protection circuit breaker, wherein the extension handle assembly comprises:

• a housing;
• a handle, installed to the housing, wherein the handle is installed to a knob of the motor protection circuit breaker upon the extension handle assembly being installed to the motor protection circuit breaker, the handle is configured to drive the knob of the motor protection circuit breaker to rotate together upon the motor protection circuit breaker being manually tripped, and to be driven to rotate together with the knob of the motor protection circuit breaker upon the motor protection circuit breaker being fault-tripped;
• during a manual tripping period of the motor protection circuit breaker, the handle is configured to drive the knob to rotate from a first position to a second position, during a fault tripping period of the motor protection circuit breaker, the knob is configured to drive the handle to rotate from the first position to a third position, the third position being located between the first position and the second position, wherein at the first position, the motor protection circuit breaker is in an ON state, at the second position, the motor protection circuit breaker is in a manual tripping state, and at the third position, the motor protection circuit breaker is in a fault tripping state;
• a stopper, pivotally installed in the housing, wherein the stopper is configured to abut against the handle upon the handle rotating from the first position to the second position during the manual tripping period of the motor protection circuit breaker, so as to provide a stopping force for a rotation of the handle to increase a force required for the rotation of the handle from the first position to the second position, and the stopper is configured not to abut against the handle upon the handle rotating from the first position to the third position during the fault tripping period of the motor protection circuit breaker, so as to not provide a stopping force for the rotation of the handle.