Abstract: A barrier arrangement for use in a multiple-phase padmounted switchgear includes a pair of insulated upper and lower barrier panels mounted in spaced vertical tandem and stationary relation one above the other so as to define a gap therebetween and an insulated intermediate barrier panel disposed adjacent to the gap between the upper and lower barrier panels. The barrier panels are disposed within an enclosure of the switchgear between the pairs of multi-phase switchgear assemblies. The intermediate barrier panel is mounted to the upper barrier panel so as to undergo sliding movement between lowered and raised positions relative to the lower barrier panel so as to respectively open and close the gap between the upper and lower barrier panels in response to insertion and withdrawal of a transversely disposed additional barrier panel through the gap.

Abstract: In an electrical distribution apparatus a switchgear device has a fixed element disposed within a shielded region of an enclosure of the apparatus, and a movable element supported for movement between a closed position in contact with the fixed element and an open position out of contact with the fixed element. The movable element is disposed at least partially within an access region of the enclosure when in the open position. A panel is supported between the shielded and access regions, and includes a slot through which the movable element passes during movement between the closed and open positions. A barrier member is movable horizontally relative to the panel between a blocking position covering the slot and a non-blocking position exposing the slot. The barrier member prevents inadvertent contact with the fixed element through the slot and prevents movement of the movable element between the open and closed positions when in the blocking position.

Abstract: In a multiple-phase electrical distribution apparatus, a number of barrier panels formed of dielectric material are provided for separating electrical transmission components disposed within the apparatus. The barrier panels may be manually placed in and lifted from a working position within the enclosure, and are supported in the working position by a mounting bracket extending horizontally in a direction parallel to the direction in which the components are spaced. The bracket includes a transverse slot disposed between the electrical transmission components and defining a pair of bearing surfaces which grip opposed surfaces of the barrier panel when the lower edge of the panel is inserted in the slot. Also, the barrier panel engages a slot formed in the enclosure above the bracket to stabilize the barrier panel against lateral movement.

Abstract: A motor operator for local or remote shifting of switchgear contacts toward either open or closed positions includes a reversible motor and rotatable drive screw mounted on common support structure for simultaneous pivoting movement as a drive nut translates fore-and-aft along the length of the screw. The drive nut includes an outer body and an inner sleeve which is set into free-wheeling motion whenever the sleeve comes into contact with either of two stops mounted on the screw defining respective end limits of travel for the nut. A drive element normally coupling the nut to an operating shaft of the switchgear is removable to allow the shaft to be manually rotated with a wrench when desired, and removal of the drive element reduces the likelihood that the worker is injured upon unintentional activation of the motor while the operating shaft is turned by hand.

Abstract: A combination dropout assembly adapted for use with protective cutouts in an electrical distribution system comprises a current limiting fuse electrically connected in series with an explusion-type fuse, and mechanically coupled in skewed relation to the latter, whereby the assembly provides reliable full range fault current protection yet is sufficiently compact in length to matingly span the gate between conductive terminals of conventional 15 KV class opengate cutouts found in many existing electrical distributioon systems. Overload and low to medium fault current protection is provided by the expulsion fuse, while high range fault currents are cleared by operation of the current limiting fuse.

Abstract: A current limiting fuse especially adapted for installation within the oil tank of a transformer for protecting the latter from the effects of high magnitude fault currents is provided which is completely fluid-submersible and capable of withstanding severe thermal cycling without damage to the fluid-tight seals thereof. In addition, the fuses hereof are especially constructed for permitting quick, individual helium testing thereof in order to ensure that the fuses meet required safety standards. The main body of the fuse is encapsulated within a fluid-impervious casing of filled epoxy material which is penetrated by a pair of opposed, end-mounted, electrically conductive terminals each being threadably connected to the body of the fuse and bearing against a respective resilient seal member to form fluid-tight seals between the opposed terminals and the apertured ends of the encapsulating casing.

Abstract: A rigid, unitary, externally mounted combination bus bar and current interrupter especially adapted for protecting pad-mounted transformers from the effects of fault currents is provided which precludes catastrophic transformer failures by ensuring that all energized parts within the transformer tank are on the protected load side of the current interrupter while also providing an external, insulated bus bar having strategically spaced, line-connecting, loop feed bushings which preclude arcing-over therebetween and permit the transformer to be safely system-installed according to established practices with preexisting feeder lines. The assembly preferably includes a rigid, encapsulated bus bar carrying a central conductor which electrically connects the spaced terminator-receiving bushings thereon in order to define an external electrical feed loop, with an integrally attached, oil-submersible high-range current limiting fuse extending from the bar and into the tank of the protected transformer.