A current transformer support device includes three plate-like conductors, each of which has a first connection portion at one end and a second connection portion at the other end, and which are aligned linearly side by side while being spaced apart from one another, and a current transformer case which integrally insulates and supports the three conductors between the one end and the other end. The current transformer support device is characterized in that the current transformer case has current transformer attachment portions provided at positions corresponding to at least two of the three conductors, to which ring-like current transformer coils formed so as to insert the conductors are attached, and that the current transformer case and the current transformer coils attached to the current transformer attachment portions are formed into one unit with a hardening insulating material.

A current transformer support device includes three plate-like conductors, each of which has a first connection portion at one end and a second connection portion at the other end, and which are aligned linearly side by side while being spaced apart from one another, and a current transformer case which integrally insulates and supports the three conductors between the one end and the other end. The current transformer support device is characterized in that the current transformer case has current transformer attachment portions provided at positions corresponding to at least two of the three conductors, to which ring-like current transformer coils formed so as to insert the conductors are attached, and that the current transformer case and the current transformer coils attached to the current transformer attachment portions are formed into one unit with a hardening insulating material.

A safety shutter of the present disclosure comprises: a base unit; a shutter unit; and a cam unit. The base unit is coupled to a cradle of an air circuit breaker, and a terminal connected to a main circuit passes through the base unit. The shutter unit is coupled to the base unit so as to be spaced apart at a predetermined interval, and accommodates the terminal in the space between the shutter unit and the base unit. The cam unit extends from the base unit and penetrates the shutter unit. The shutter unit deactivates insulation by exposing the terminal in the direction of the air circuit breaker when the air circuit breaker is inserted in the direction of the base unit.

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 handle 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.

Disclosed in the present invention is an electric switching apparatus, comprising a drawer apparatus, an electric connection apparatus, a driving mechanism, and a locking mechanism. The driving mechanism drives a breaker body to move; the relative positions of the breaker body and the drawer apparatus comprise: a separate position, a trial position, a connected but not clamped position, and a connected and clamped position. A busbar of the breaker body at the separate position is separated from the electric connection apparatus, and the breaker body cannot be switched on. The busbar of the breaker body at the trial position is separated from the electric connection apparatus, and the breaker body can be switched on. The busbar of the breaker body at the connected but not clamped position is in touch with the electric connection apparatus, the electric connection apparatus does not clamp the busbar, and the breaker body cannot be switched on. The busbar of the breaker body at the connected and clamped position is in touch with the electric connection apparatus, the electric connection apparatus clamps the busbar, and the breaker body can be switched on.

Disclosed in the present invention is an electric switching apparatus, comprising a drawer apparatus, an electric connection apparatus, a driving mechanism, and a locking mechanism. The driving mechanism drives a breaker body to move; the relative positions of the breaker body and the drawer apparatus comprise: a separate position, a trial position, a connected but not clamped position, and a connected and clamped position. A busbar of the breaker body at the separate position is separated from the electric connection apparatus, and the breaker body cannot be switched on. The busbar of the breaker body at the trial position is separated from the electric connection apparatus, and the breaker body can be switched on. The busbar of the breaker body at the connected but not clamped position is in touch with the electric connection apparatus, the electric connection apparatus does not clamp the busbar, and the breaker body cannot be switched on. The busbar of the breaker body at the connected and clamped position is in touch with the electric connection apparatus, the electric connection apparatus clamps the busbar, and the breaker body can be switched on.

A medium-voltage switchgear system includes a three-phase circuit breaker having first, second and third single-phase vacuum interrupters connected between respective first, second and third single-phase inputs and first, second and third single-phase outputs. Magnetic actuators are connected to first, second and third single-phase vacuum interrupters, which are configured to receive an interrupt signal and in response, actuate the respective vacuum interrupter connected thereto into an open circuit condition. A controller circuit is connected to each of the first, second and third magnetic actuators and generates an interrupt signal in response to a detected single-phase overcurrent or fault on a single-phase circuit and interrupt that single-phase circuit on which the single-phase overcurrent or fault occurred and maintain power on the remaining two single-phase circuits over which a single-phase overcurrent or fault was not detected.

An interlock system for a switchgear cabinet of a drawout switchgear device includes a guide rail in the cabinet to align rollers supporting the drawout switchgear device. A stop plate is spring biased toward a blocking position to block the rollers from rolling off the guide rail. A deflector surface on the stop plate receives a contact force from a fastener hook of a lift truck, to move the stop plate and unblock the rollers. The fastener hook then anchors the lift truck to the cabinet after the stop plate has moved away from the blocking position. A bridging guide rail mounted on the lift truck, aligns with and abuts the guide rail in the cabinet to allow the drawout switchgear device to be safely rolled into or withdrawn from the cabinet by an unassisted service person operating the lift truck.

A medium-voltage switchgear system includes a three-phase circuit breaker having first, second and third single-phase vacuum interrupters connected between respective first, second and third single-phase inputs and first, second and third single-phase outputs. Magnetic actuators are connected to first, second and third single-phase vacuum interrupters, which are configured to receive an interrupt signal and in response, actuate the respective vacuum interrupter connected thereto into an open circuit condition. A controller circuit is connected to each of the first, second and third magnetic actuators and generates an interrupt signal in response to a detected single-phase overcurrent or fault on a single-phase circuit and interrupt that single-phase circuit on which the single-phase overcurrent or fault occurred and maintain power on the remaining two single-phase circuits over which a single-phase overcurrent or fault was not detected.

A safety shutter of the present disclosure comprises: a base unit; a shutter unit; and a cam unit. The base unit is coupled to a cradle of an air circuit breaker, and a terminal connected to a main circuit passes through the base unit. The shutter unit is coupled to the base unit so as to be spaced apart at a predetermined interval, and accommodates the terminal in the space between the shutter unit and the base unit. The cam unit extends from the base unit and penetrates the shutter unit. The shutter unit deactivates insulation by exposing the terminal in the direction of the air circuit breaker when the air circuit breaker is inserted in the direction of the base unit.