Northern Engineering Industries Plc

Westinghouse Electric Corporation

Thomas Kelsey

Charles F Cromer

Kue H Yoon

Robert L Hess

Michael G Caithness

Peter Headley

John Murdy

In or for a fluid-filled metal-clad switchgear an automatically-operating device for short-circuiting an internal arc in the earthed metal enclosure comprises a piston movable in a cylinder mounted on the enclosure wall, with a rod projecting towards the interior space filled with insulating medium. A pipe or other means connects the space to the cylinder at the remote side of the piston, so that on occurrence of an internal arc in the enclosure the rapid pressure rise creates a pressure differential across the piston to drive it and the rod inwardly and cause the rod to engage the high-voltage conductor and short-circuit the arc to the earthed enclosure. The piston is held normally by a spring or by breakable pegs.

Arc shorting device

A gas-insulated circuit interrupter includes stationary and movable contact assemblies which are cooperable with each other to transmit or interrupt electrical current. Means are provided for moving the movable contact assembly, and for establishing a flow in the circuit interrupter during an opening interruption to estinguish the arc which is drawn between the stationary and movable arcing contacts. A hollow insulating nozzle is utilized for directing gas flow. The interior surface of the nozzle is shaped so as to direct a flow of insulating gas to blast into the arc, and the exterior surface of the nozzle is contoured such as to deflect the flow of insulating gas away from the movable main contacts.

Gas-insulated circuit-interrupter having improved insulating nozzle

Growing community of inventors

Northumberland, United Kingdom

Thomas Kelsey