Electrical switching device are disclosed having a housing with internal component within the housing. The internal components comprise contacts configured to operate, to change the state of the switching device from a closed state, allowing current flow through the switching device to an open state which interrupts current flow through the switching device. A pyrotechnic feature is included that is configured to interact with the internal components to transition the switching device from the closed state to the open state when the pyrotechnic feature is activated. The pyrotechnic feature is configured to trigger in response to levitation between the contacts at elevated current signal flowing through the switching device.

An electromagnetic trip unit, wherein: the electromagnetic trip unit includes a movable core, an upper static core and a lower static core; the movable core can move relative to the upper static core and the lower static core in the upper static core and the lower static core; a movable core body end of a movable core body of the movable core faces and approaches the lower static core end of the lower static core, when the electromagnetic trip unit is not released, a first magnetic field air gap is formed between the movable core body end and the lower static core end; the movable core body of the movable core is also provided with a movable core body step, when the electromagnetic trip unit is not released, a second magnetic field air gap is formed between the movable core body step and the lower static core end.

A method for adjusting a magnetic release mechanism includes steps: a first measurement of the present release current I of the magnetic release mechanism is carried out, a decision is made as to whether an adjustment step is performed, a start-adjustment current I.sub.J0 is selected, a second measurement of the present release current I of the magnetic release mechanism is carried out, a decision is made as to whether an adjustment step is performed and that in the event that an adjustment step is necessary, a selection of a certain differential amount ΔI.sub.J takes place, partial demagnetisation of the permanent magnet is carried out in a further adjustment step with the adjustment current I.sub.J formed in this way and the steps are carried out in succession until the release current I measured lies within a specified range between I.sub.TARGET.sub._.sub.min and I.sub.TARGET.sub._.sub.max.

A circuit protection apparatus includes separable contacts, an operating mechanism, an electronic trip unit storing a plurality of trip parameter combinations, wherein each of the trip parameter combinations specifies a certain value for each of a plurality of individual trip parameters, and a multi-position selector moveable among a plurality of predetermined positions and configured to enable selection of one of the predetermined positions. Each of the positions corresponds to a respective one of the trip parameter combinations, wherein the electronic trip unit is structured to, responsive to a chosen one of the plurality of predetermined positions being selected by the multi-position selector, cause the one of the trip parameter combinations corresponding to the chosen one of the plurality of predetermined positions to be used by the electronic trip unit to determine whether to cause the operating mechanism to trip open the separable contacts.

A circuit protection apparatus includes separable contacts, an operating mechanism, an electronic trip unit storing a plurality of trip parameter combinations, wherein each of the trip parameter combinations specifies a certain value for each of a plurality of individual trip parameters, and a multi-position selector moveable among a plurality of predetermined positions and configured to enable selection of one of the predetermined positions. Each of the positions corresponds to a respective one of the trip parameter combinations, wherein the electronic trip unit is structured to, responsive to a chosen one of the plurality of predetermined positions being selected by the multi-position selector, cause the one of the trip parameter combinations corresponding to the chosen one of the plurality of predetermined positions to be used by the electronic trip unit to determine whether to cause the operating mechanism to trip open the separable contacts.

An adjustable thermal trip mechanism for a circuit breaker is provided which can improve the reliability of over-current tripping by minimizing an influence upon thermal tripping even if an assembly error such as skewing or twisting occurs during assembly of bimetallic strips. The adjustable thermal trip mechanism for the circuit breaker comprises: a crossbar that is rotatable and has at least one power receiving portion for receiving rotary power; a bimetallic strip that can bend towards the power receiving portion when an over current occurs on the circuit; and an adjustment screw installed to face the power receiving portion, wherein the power receiving portion comprises a plurality of planar portions which are at different distances from the adjustment screw.

Electrical switching device are disclosed having a housing with internal component within the housing. The internal components comprise contacts configured to operate, to change the state of the switching device from a closed state, allowing current flow through the switching device to an open state which interrupts current flow through the switching device. A pyrotechnic feature is included that is configured to interact with the internal components to transition the switching device from the closed state to the open state when the pyrotechnic feature is activated. The pyrotechnic feature is configured to trigger in response to levitation between the contacts at elevated current signal flowing through the switching device.

The present disclosure relates to a molded case circuit breaker, and particularly, to a molded case circuit breaker having an enhanced arc protecting function. The molded case circuit breaker includes: a power side terminal portion provided at a front side of an enclosure and having a fixed contact arm; a finger assembly coupled to the fixed contact arm, and disposed on a front surface of the power side terminal portion; and a base bus supporter coupled to an upper surface and a lower surface of the power side terminal portion, and having a finger hole through which the finger assembly is exposed. The base bus supporter is provided with a protection unit configured to enclose the finger assembly around the finger hole.

The present disclosure relates to a molded case circuit breaker, and particularly, to a molded case circuit breaker having an enhanced arc protecting function. The molded case circuit breaker includes: a power side terminal portion provided at a front side of an enclosure and having a fixed contact arm; a finger assembly coupled to the fixed contact arm, and disposed on a front surface of the power side terminal portion; and a base bus supporter coupled to an upper surface and a lower surface of the power side terminal portion, and having a finger hole through which the finger assembly is exposed. The base bus supporter is provided with a protection unit configured to enclose the finger assembly around the finger hole.

Disclosed herein are passive triggering mechanisms for activation of pyrotechnic features within electrical switching devices, such as contactor devices and fuse devices. The activation of the pyrotechnic features is configured to change the configuration of the internal components of the switching device and prevent current flow through the device. In some embodiments, the triggering mechanisms comprise features that respond to a magnetic field, such as a reed switch. In some embodiments, the reed switch responds to elevated current flow and can then use the signal with the elevated current flow to activate the pyrotechnic feature. In other embodiments, the reed switch uses a power signal from a secondary power source to activate the pyrotechnic feature.