An electronic trip unit is for a low-voltage circuit breaker of a three-phase AC circuit. The electronic trip unit includes a housing with a front, rear, left-hand, right-hand, top and bottom face; a controller to compare current measurement values of the three-phase AC circuit with at least one of current limit values, current period limit values and time period limit values and to output a tripping signal, for interrupting the three-phase AC circuit, upon the values being exceeded. The electronic trip unit further includes a receptacle to provide a connection between the electronic trip unit and the module, the module being receivable by the left-hand, right-hand, top or bottom side face of the housing. At least one function of the electronic trip unit is activated upon the module being received. The front face of the housing includes a viewing window. At least a portion of a received module is visible.

A multi-level feedback actuator assembly for a circuit breaker assembly including an interlock system. The interlock system for the multi-level feedback actuator assembly is structured to maintain the multi-level feedback actuator assembly, and elements thereof, in a safe configuration. The interlock system for the multi-level feedback actuator assembly includes an interlock assembly structured to configure the rotary solenoid and at least one of the first actuator or the second actuator in a safe configuration.

A switching mechanism for a dual power supply transfer switch. The switching mechanism has a switching assembly, which includes a driving plate, a driving rod, an actuator and an auxiliary mechanism. The driving plate includes an arc-shaped driving groove. The driving rod extends into the driving groove. The auxiliary mechanism includes a spring. The driving plate is able to rotate under an external force. The driving groove bypasses the driving rod when an end of the driving groove does not contact the driving rod, and the driving groove pushes the driving rod to rotate over a first angle and urges the spring to deform when the end of the driving groove contacts the driving rod. The spring recovers and drives the driving rod to rotate over a second angle after the spring having passed a dead point, thus causing the actuator turning on or off a first power supply. The switching mechanism also includes another switching assembly for switching a second power supply. A dual power supply transfer switch including the switching mechanism also is provided.

A locking mechanism for a circuit breaker operation device includes a housing (1). A button (2) is mounted in a button slot (101) of the housing (1). The locking mechanism is characterized in that the housing (1) is provided with a locking member (3) therein, and the locking member (3) can lock or unlock the button (2). In the locking mechanism for a circuit breaker operation device, a locking member is added in the circuit breaker; only after a lock button is pressed, an operation button is pressed to close the circuit breaker; when the operation button is pulled out, the circuit breaker is disconnected; when the lock button is not pressed, the operation button is locked by the lock button, the operation button cannot be pressed down, the circuit breaker cannot be closed.

A locking mechanism for a circuit breaker operation device includes a housing (1). A button (2) is mounted in a button slot (101) of the housing (1). The locking mechanism is characterized in that the housing (1) is provided with a locking member (3) therein, and the locking member (3) can lock or unlock the button (2). In the locking mechanism for a circuit breaker operation device, a locking member is added in the circuit breaker; only after a lock button is pressed, an operation button is pressed to close the circuit breaker; when the operation button is pulled out, the circuit breaker is disconnected; when the lock button is not pressed, the operation button is locked by the lock button, the operation button cannot be pressed down, the circuit breaker cannot be closed.

Implementations of the subject matter described herein provide a switching apparatus. The switching apparatus includes: a switching component including a first main shaft, which is adapted to selectively connect and disconnect at least one circuit in response to the rotation of the first main shaft; and an operating mechanism including a second main shaft for actuating the first main shaft to rotate via the second main shaft; wherein the switching component further includes a first interface, and the operating mechanism further includes a second interface, and the second main shaft to be detachably coupled to the first main shaft in response to the engagement of the first interface and the second interface.

Implementations of the subject matter described herein provide a switching apparatus. The switching apparatus includes: a switching component including a first main shaft, which is adapted to selectively connect and disconnect at least one circuit in response to the rotation of the first main shaft; and an operating mechanism including a second main shaft for actuating the first main shaft to rotate via the second main shaft; wherein the switching component further includes a first interface, and the operating mechanism further includes a second interface, and the second main shaft to be detachably coupled to the first main shaft in response to the engagement of the first interface and the second interface.

Motor control centers have units or buckets with an extendable/retractable power connection (stab) assembly and one or more operating lever interlocks that include a unit latch to latch to a cabinet and a power connection position interlock that blocks the handles of the units or buckets based on position of the power connection assembly, optionally also including a shutter cam that slides a shutter right and left.

Motor control centers have units or buckets with an extendable/retractable power connection (stab) assembly and one or more operating lever interlocks that include a unit latch to latch to a cabinet and a power connection position interlock that blocks the handles of the units or buckets based on position of the power connection assembly, optionally also including a shutter cam that slides a shutter right and left.

Implementations of the subject matter described herein provide a switching apparatus. The switching apparatus includes: a handle shaft coupled to a handle and arranged rotatable in a circumferential direction in response to an operation to the handle; and a locking plate arranged movable in a first direction in association with a rotation of the handle shaft. The handle shaft and the locking plate are operable to limit the rotation of the handle shaft when the handle shaft arrives at an off position of the switching apparatus.