Disclosed herein is a switching apparatus for medium voltage electric systems, said switching apparatus including one or more electric poles. For each electric pole, said switching apparatus includes: a first pole terminal, a second pole terminal, and a ground terminal; a first fixed contact member and a first movable contact member, said first fixed contact member being electrically connected to said first pole terminal and including a first fixed contact, said first movable contact member being electrically connected to said second pole terminal and including a first movable contact; a second fixed contact member and a second movable contact member, said second fixed contact member being electrically connected to said first pole terminal and including a second fixed contact, said second movable contact member including a second movable contact; a vacuum chamber, in which said second fixed contact and said second movable contact are enclosed; and a motion transmission mechanism.

In a switch in which one end portion of a blade is pivotally attached to a fixed contactor and another end portion of the blade is brought into pressure contact with a fixed contactor by rotational operation of the blade, at least one slit is provided in each of a conductive contact surface, with respect to the fixed contactor, of the one end portion of the blade and a conductive contact surface, with respect to the fixed contactor, of the other end portion of the blade, so as to divide each of the conductive contact surfaces, thereby achieving multi-point contact on each of the conductive contact surfaces, and a thickness of a contact-pressure spring fixing portion of the blade at which a contact-pressure spring for bringing the other end portion into pressure contact with the fixed contactor is made smaller than that of the other end portion.

In a switch in which one end portion of a blade is pivotally attached to a fixed contactor and another end portion of the blade is brought into pressure contact with a fixed contactor by rotational operation of the blade, at least one slit is provided in each of a conductive contact surface, with respect to the fixed contactor, of the one end portion of the blade and a conductive contact surface, with respect to the fixed contactor, of the other end portion of the blade, so as to divide each of the conductive contact surfaces, thereby achieving multi-point contact on each of the conductive contact surfaces, and a thickness of a contact-pressure spring fixing portion of the blade at which a contact-pressure spring for bringing the other end portion into pressure contact with the fixed contactor is made smaller than that of the other end portion.

Apparatus detects an electrical fault in a primary tap having a plurality of distribution transformers each provided in a distribution circuit along a length of the primary tap, on a power distribution system. The apparatus includes a voltage monitor provided at each of the distribution circuits for monitoring a voltage in a corresponding distribution circuit, a controller in communication with each of the voltage monitor for receiving the voltage monitored and transmitted by the voltage monitors, and a fuse isolator configured to electrically connect the primary tap to a high voltage on the power distribution system and electrically disconnect the primary tap from the high voltage on power distribution system when activate. A fuse isolator actuator in communication with the controller is provided for activating the fuse isolator responsive to a control signal from the controller when a fault in the primary tap is detected by the controller, which determines that a fault exists in the primary tap based on the voltages monitored by the plurality of voltage monitors.

A switchgear having bus transfer current switching capability by a turn and twist mechanism that includes a contact system for electrical current conduction and bus transfer switching is provided. The contact system has fixed and movable contact assemblies. Each contact assembly includes main contacts and arcing contacts. The arcing contacts are for bus transfer switching. The movable contact assembly includes a current path pipe and an end piece. The current path pipe is a cylindrical pipe, and the end piece is a rectangular block. The movable contact assembly includes a movable main contact provided on the rectangular block, and a movable arcing contact provided at the end of the cylindrical pipe on a portion about the periphery. During engagement, the cylindrical pipe turns about a first axis to bring the contact assemblies proximal to each other, and twists about a second axis for engagement of the main contacts.

A switch including a blade, an electrical terminal, and a inclinometer sensor. The blade is pivotable between an open position and a closed position. The electrical terminal is configured to receive the blade when in the closed blade position. The inclinometer sensor is coupled to the blade. The inclinometer sensor is configured to sense a position of the blade and output a signal corresponding to the position.

A switch including a first electrical terminal, the first electrical terminal including a blade pivotable between an open position and a closed position, and a rod extending from the first electrical terminal parallel to the blade. The switch further includes a second electrical terminal configured to receive the blade when in the closed position, the second electrical terminal including a vacuum interrupter, wherein the vacuum interrupter engages the rod when in the closed position. Rotating the first electrical terminal in a first direction causes the blade to disengage from the second electrical terminal at a first point, and further rotating the first electrical terminal in the first direction causes the rod to disengage from the vacuum interrupter at a second point.

A support structure for a HVDC disconnector is disclosed. The support structure comprises a support insulator having a body enclosing a chamber; an insulating gas provided in the chamber; and a first flange and a second flange positioned at opposite ends of the support insulator. A rotating insulator may be positioned in the chamber.

Embodiments of the present disclosure provide a flexible conductor for connecting a main blade and a base of a disconnector. The flexible conductor includes a first portion and a second portion, the first portion is fixed to the base and adapted to bend in a first plane in response to a rotation of the main blade about a first axis; and the second portion is connected to the first portion and fixed to the main blade, the second portion adapted to bend in a second plane substantially perpendicular to the first plane in response to twisting of the main blade about a second axis; wherein the flexible conductor is operable to maintain an electrical connection between the main blade and the base when the main blade rotates and twists with respect to the base to open or close the disconnector.

Embodiments of the present disclosure provide a flexible conductor for connecting a main blade and a base of a disconnector. The flexible conductor includes a first portion and a second portion, the first portion is fixed to the base and adapted to bend in a first plane in response to a rotation of the main blade about a first axis; and the second portion is connected to the first portion and fixed to the main blade, the second portion adapted to bend in a second plane substantially perpendicular to the first plane in response to twisting of the main blade about a second axis; wherein the flexible conductor is operable to maintain an electrical connection between the main blade and the base when the main blade rotates and twists with respect to the base to open or close the disconnector.