Abstract: A manually actuable load break switch actuated having a base mounted on one end of a vacuum actuated switch, an operating lever pivotally mounted on the base and operatively connected to open and close the vacuum switch, a toggle mechanism connected to the end of the operating lever, the toggle member including a compression spring for biasing the operating lever to the closed position, a manually actuated handle pivotally mounted on said base for tripping the toggle mechanism by movement from one side of the toggle mechanism to the other, spring means operable connecting the handle to the toggle mechanism, and a lock pin biased into engagement with the end of the lever to lock the lever in the switch open position.

Abstract: The insulating housing of a high voltage splice or terminator for a high voltage electrical distribution system comprises a connector cavity defined by a hollow electrically conductive stress relief insert and at least one or more cable-receiving passages communicating with the connector cavity. A stripped electrical conductor at the end of a cable extends through the passage and is electrically and mechanically joined to a metal electrical connector in the cavity as by crimping. A hollow elastomeric electrically conductive and thermally conductive heat transfer device, split along one side to enable it to be slipped into the electrical connector, makes snug electrical and thermal engagement with the exterior of the connector and has integrally formed radially outwardly extending spaced apart resilient projections on its outer surface for making tight electrical and thermal engagement with the interior surface of the hollow stress relief insert of the housing.

Abstract: A temperature-responsive trip assembly for a primary circuit breaker, the assembly including a permanent magnet member biased to a circuit opening position and pertinent to engage a thermally-responsive metallic element having a predetermined Curie temperature, the element being formed of a nickel-iron alloy having approximately 32% nickel and being arranged in edge-abutting relation to the magnet.

Abstract: A dual voltage under oil transformer switch formed from one or more phase switch units, fuse switch units and/or auxiliary switch units, each switch unit including a standardized molded switch block, shaft and rotor, the switch blocks including a contact deck for supporting a number of contact blades in a common plane, the rotor including a number of bridge contacts each having a number of double-bladed contact fingers for electrically engaging the contact blades, the rotor being mounted for axial movement on the shaft to accommodate variations in the planar position of the bridge contacts, the shafts being adopted for interlocking engagements and an operating handle assembly for positively locating and indicating the position of the switch position of the rotor in its switch block, the operating handle assembly, switch block, rotor and shafting having physical index members to assure proper interconnection of the switch units.

Abstract: A primary power circuit breaker adapted to be immersed in the dielectric fluid for a transformer, the breaker including an arc interrupting assembly for extinguishing the arc produced on load break; a trip free mechanism responsive to primary, secondary or primary-secondary differential current signals and thermally responsive to fluid temperature, and an externally operable reset assembly for closing the circuit breaker.

Abstract: A current-limiting fuse comprises a hollow insulating housing; metallic end cap assemblies at opposite ends of the housing; a multi-ribbed dielectric spider assembly having metallic terminator plates connected at opposite ends disposed within the housing with each terminator plate electrically and mechanically connected to an associated end cap assembly; a plurality of fusible elements helically wound on the spider assembly with their ends electrically and mechanically secured to the terminate plate; a visual indicator pin mounted on one end of the spider assembly and movable by a biasing spring from a retracted position wherein it is secured by a fusible wire to a tripped (fuse-blown) position wherein it projects through aligned holes in an associated terminator plate and end cap assembly; and granular dielectric material filling the housing.

Abstract: An elastomeric insulated fully shielded arrester including one or more surge arrester blocks mounted within an elastomeric housing having a layer of conductive material on the outer surface thereof, an electrically conductive contact at each end of the arrester block, the elastomeric housing providing a compressive force for maintaining electrical communication between the electrical contacts and the block or blocks and closely engaging the outer surface of the block or blocks to minimize corona discharge.

Abstract: A primary circuit breaker for fluid filled transformers, the circuit breaker being immersible in the fluid in the transformer and including a circuit interrupter assembly, an externally actuatable latch mechanism for reclosing the interrupter assembly and a magnetically controlled trip assembly for releasing the interrupter assembly from the latch mechanism in response to predetermined electrical and thermal conditions in the transformer.

Abstract: An energy-limited fuse having a number of fuse elements spirally wrapped about a spider formed from a number of insulating plates, the fuse elements being supported in a parallel spaced relation at a distance sufficient for each element to operate independently and a striker pin assembly independently mounted in said fuse after said spider assembly has been mounted in said fuse, said striker pin assembly including a vaporizable wire for holding the striker pin in said striker pin assembly until the fuse elements are vaporized.

Abstract: A bayonet-type circuit breaker or under oil fuse device for completing the circuit from a high voltage bushing to an under oil transformer, the bayonet type device including a bayonet assembly having a circuit element at the end and a support assembly mounted on the transformer tank and having a tubular portion extending into the oil in the tank, the tubular portion including a pair of skirts at each contact location on the tubular portion and an elongate band of conductive spring metal material bent into a square configuration and having a number of spring fingers integrally formed along the axis of the band with a contact button on the free end of each finger, the band being mounted on the tubular portion of the support assembly between the skirts in a position to engage the circuit element, the inherent bias of the fingers holding the buttons in engagement with the contacts at each end of the circuit element.

Abstract: A gapless arrestor assembly for a high voltage bushing including an insulating elastomeric housing having a bore formed in one portion thereof and a receptacle formed in another portion thereof and a surge arrester assembly positioned in the bore in said housing, the arrester assembly being formed from one or more surge arrester blocks and including a connector element at the inner end of the arrester blocks, the connector element being movably connected to the surge arrester blocks and a probe contact positioned in the receptacle and rigidly connected to the connector element, the connector element allowing movement of the probe contact independent of the arrester blocks.

Abstract: This invention relates generally to underground electric power distribution systems. In particular, it relates to underground loop feed circuits which include reclosers and transformers and a plurality of high frequency actuated normally closed isolator switches for automatically locating and sectionalizing portions of the loop circuit in which faults originate. The actuator switches between which a fault occurs are armed in response to a fault current and only those switches which are armed are opened thereby isolating the faulted section of cable. The remaining actuator switches remain closed.

Abstract: A blown fuse indicator for an electric fuse having a tubular casing of insulating material, a pair of terminal caps mounted on the ends of the casing to close the ends thereof, a fuse link conductively interconnecting the terminal caps and an arc quenching filler material filling the casing to embed the fuse link, the fuse indicator including an indicator housing supported by one of the end caps, a pin type indicator positioned within the housing and biased outwardly from the housing to pierce a plate provided at the outer end of the indicator housing and a pair of members formed of a non-conductive material and having a plurality of corresponding opening in the form of holes or notches with a fuseable wire threaded through the openings to prevent relative movement between the members, one of the members being supported by the housing and the other of the members being connected to the indicator, on fusing of the wire the member connected to the indicator being released allowing the indicator to move to the i

Abstract: A drywell fuse holder and a loadbreak fuse assembly, the holder including an arc-extinguishing sleeve located adjacent to the inner contact sleeve, the loadbreak fuse assembly including a non-expulsion fuse having electrical interface assemblies at each end spaced apart a distance less than the distance the inlet to the contact sleeves in the fuse holder, the interface assemblies including a spacer ring to center the fuse assembly in the holder and protect the garter spring contact and an arcing washer to transfer the arc from the garter spring; and an arc-extinguishing follower on the fuse assembly which is pulled through the arc-extinguishing sleeve to extinguish the arc.

Abstract: An oil capable of use in environments where the accumulation of water is detrimental to the intended use, the oil consisting of branched and straight chain aliphatic hydrocarbons and minor amounts of tri-cresyl phosphate.

Abstract: A continuous conductor pattern applied to a dielectric cooking utensil improves the distribution of microwave energy to the bottom surface of food being cooked. The energy is coupled from the electromagnetic field within the oven cavity by metal strip pickup probes on the hand grips or side walls which are part of the embedded metal layer. The conductor pattern on the bottom wall couples energy from the pickup probes to the central region of the utensil.

Abstract: A high current under oil expulsion fuse having a pair of contacts mounted on a dielectric sleeve, a nontracking, nonconducting pressure tube within the sleeve which extends beyond the dielectric housing into a portion of each of the contacts, a fuse link in the pressure tube, a clamp having a metering orifice mounted on one of the contacts to secure the link in the contact and a gas retention chamber mounted on the other contact to secure the link to the other contact, the gas retention chamber being operative to blow high pressure gas through the bore of the pressure tube to assist in clearing arc products and ionized gases from the fuse.

Abstract: A liquid composition and method for forming the composition, the composition being intended for use in an oil-filled electrical apparatus to minimize the detrimental effects that can occur during high fault conditions which oil composition is biodegradable and formed from natural hydrocarbons and synthetic hydrocarbons which when combined form a flat pseudo-rectangular molecular weight distribution curve.

Abstract: A six rib spider assembly for a fuse including a dielectic housing having end caps for supporting the spider assembly within the housing and a fusable ribbon helically wound on the spider assembly, the housing being filled with a granular dielectic material. The spider assembly including three mica plates each having a number of notches in their longitudinal edges to define support surfaces along each longitudinal edge for the fusable ribbon. These support surfaces on each longitudinal edge being offset from the support surfaces on the opposite longitudinal edge as well as from the support surfaces on each of the other mica plates. Each plate also including at least one longitudinal slot intermediate the longitudinal edges of the plate with one of the plates including a second slot, whereby the plates can be cross fitted into each other with the plates angularly related so that the support surfaces define a helical path for the fusable ribbon.

Abstract: A relay for tripping a circuit breaker in a high voltage power line, the relay including a current transformer having first and second turns ratios, a heat radiation circuit including a plurality of lamps connected to the current transformer and a sensing circuit including a phototransistor which responds to heat radiation from one of said lamps, the turns ratios and lamps being selectively connectable to provide different minimum trip current levels of the relay.