A circuit breaker with an integrated motorized racking mechanism, automatically provides electrical power to the racking motor when the breaker is inserted into a breaker compartment. The racking motor remains powered when the breaker is in either a disconnected position, a testing position, or a fully connected position. A racking power plug mounted within the circuit breaker conducts electrical power to the racking motor by automatically connecting to a stationary racking power receptacle mounted in the breaker compartment, and remains connected as the circuit breaker moves through the breaker compartment during the racking operation. A control power plug is mounted in the circuit breaker to connect to a stationary control power receptacle mounted in the breaker compartment and to conduct control power to control circuits in the circuit breaker after the racking motor has completed racking the circuit breaker into the connected position in the breaker compartment.

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 high voltage electric switchboard in which manufacturing productivity is greatly improved and each functional part can be easily replaced and repaired is provided. In the high voltage electric switchboard, a plurality of functional parts including a bus bar part, a measurement and supervisory controller, a circuit breaker part, a wire part, and potential transformer part are independently modularized such that the functional parts do not have a shared surface with each other and at least two outer surfaces of an enclosure of each of the modularized functional parts are installed to be in contact with an outer surface of an enclosure of another functional part adjacent in a horizontal direction or a vertical direction.

A contact arm assembly includes a contact arm defining a central axis and having a first end configured for electrical connection with a pole of a circuit breaker and a second end having a distal end defining a shoulder and an engagement that protrudes from the contact arm proximal to the shoulder. A plurality of contact fingers are mounted circumferentially on the second end of the contact arm and configured to electrically engage a primary circuit contact. Each contact finger has a body with a depression that receives the engagement for electrical contact.

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 switchgear system may include a switchgear frame and a truck carrying a circuit breaker and supported for linear movement on the switchgear frame. A drive mechanism may rack in the truck and the circuit breaker is in electrical connection with primary circuit contacts, and may rack out the truck and the circuit breaker is electrically disconnected from the primary circuit contacts. As the drive mechanism racks in the circuit breaker, a shutter linkage moves a shutter opened, and as the drive mechanism racks out the circuit breaker, the shutter linkage moves the shutter closed over the primary circuit contacts.

A switchgear system may include a switchgear frame and a truck carrying a circuit breaker and supported for linear movement on the switchgear frame. A drive mechanism may rack in the truck and the circuit breaker is in electrical connection with primary circuit contacts, and may rack out the truck and the circuit breaker is electrically disconnected from the primary circuit contacts. As the drive mechanism racks in the circuit breaker, a shutter linkage moves a shutter opened, and as the drive mechanism racks out the circuit breaker, the shutter linkage moves the shutter closed over the primary circuit contacts.

A circuit breaker racking system includes an electrical drive operatively connected to a mechanical racking mechanism that carries the circuit breaker and moves the circuit breaker between a connect position and a disconnect position within a cubicle, and a circuit breaker trip unit that receives remote commands and controls the electrical drive based on the remote commands. A switchgear system including at least one circuit breaker with an integrated auto-racking system is also provided.

A switchgear system includes a switchgear frame having an interior compartment and front opening and containing therein at least one electrical switchgear component. A truck carries an electrical component and is supported for movement on the switchgear frame. A drive mechanism connects the truck and is configured to rack in the truck into an electrically connected position with the at least one electrical switchgear component, rack out the truck from the electrically connected position into an electrically disconnected position, and rotate the truck upward from its disconnected position into a rotated position to allow operator access through the front opening to the at least one electrical component.

A circuit breaker racking system includes an electrical drive operatively connected to a mechanical racking mechanism that carries the circuit breaker and moves the circuit breaker between a connect position and a disconnect position within a cubicle, and a circuit breaker trip unit that receives remote commands and controls the electrical drive based on the remote commands. A switchgear system including at least one circuit breaker with an integrated auto-racking system is also provided.