Abstract: The present invention comprises a mixture of hydrocarbons having a well-defined chemical composition that is suitable for use as a dielectric coolant in electrical equipment in general, and specifically in transformers. The dielectric coolants of the present invention are particularly suited for use in sealed, non-vented transformers, and have improved performance characteristics, including decreased degradation of the paper insulating layers, as well as a greater degree of safety and environmental acceptability. The present dielectric coolants comprise relatively pure blends of compounds selected from the group consisting of aromatic hydrocarbons, polyalphaolefins, polyol esters, and natural vegetable oils, along with additives to improve pour point, increase stability and reduce oxidation rate.

Abstract: An improved circuit for activating a high side mosfet drive during a predetermined phase of the A/C cycle. The circuit includes an electronic switch which is connected to an A/C line. The switch operates between an open and closed position. Also included is a mosfet drive connected to the A/C line. The mosfet drive is activated when the switch is in an open position and is deactivated when the switch is in a closed position. The circuit may also include a capacitor connected to the A/C line. The capacitor is charged during the positive phase of the A/C cycle and powers the mosfet drive during the negative portion of the A/C cycle when the switch is in an open position.

Abstract: In one aspect, the present invention provides a dielectric fluid for use in electrical equipment comprising a vegetable oil or vegetable oil blend. In another aspect the invention provides devices for generating and distributing electrical energy that incorporate a dielectric fluid comprising a vegetable oil or vegetable oil blend. Methods of retrofilling electrical equipment with vegetable oil based dielectric fluids also are provided.

Abstract: A dielectric fluid system for use in electrical equipment comprising a dielectric fluid comprising vegetable oil and an oxidation reducing composition encased in a housing composed of a polymeric material that is substantially permeable to oxygen. The oxidation reducing composition is placed inside the electrical equipment such that it is in contact with a headspace defined by the dielectric fluid. Devices generating and distributing electrical energy incorporating the above-described dielectric fluid system and method of retrofilling such devices also are provided.

Abstract: A socket spring is designed to be installed in at least two different types of reflectors. The socket spring includes a base that can be connected to a lamp socket, a first arm and a second arm. The first arm extends from the base and includes a first bend near the base for use in connecting to a first reflector and a second bend further away from the base for use in connecting to a second reflector. The second arm extends from the base and includes a first bend near the base for use in connecting to the first reflector and a second bend further away from the base for use in connecting to the second reflector. Installing the socket spring in the first reflector includes mounting the first bends to the first reflector and installing the socket spring in the second reflector includes mounting the second bends to the second reflector.

Abstract: A dead front system provides fluid access to an electrical connector and cable. The dead front system includes an injection plug, a fluid access system, and a tube connected at a first end to the injection plug and at a second end to the fluid access system. The injection plug, fluid access system, and tube are surrounded by a conductive, grounded surface.

Abstract: A high voltage electrical connector (50) interconnects sources of energy, such as transformers and circuit breakers, to distribution systems and the like via a high voltage cable (37). The high voltage electrical connector (50) includes an access cavity (58) providing access to the interior of the electrical connector. The access cavity (58) may be fitted with an insert plug (20) or an insert injection plug (120). The inserts (20, 120) include a conductive shield (36, 136) to reduce the possibility of electrical discharges from the inserts.

Abstract: A current interrupter (4) includes a current interrupting device (4) having at least one movable contact (71); an actuator (8) coupled to the movable contact (71) of the current interrupter (4); a feedback sensor (14) for monitoring movement of the actuator (8); and a control system (12) coupled to the feedback sensor (14) so as to receive information from the feedback sensor (14) concerning the movement of the actuator (8) and for controlling movement of the actuator (8) based on the information. The interrupter (4) further includes a memory (202) for storing a desired motion profile of the actuator (8); and a microprocessor (202) for comparing the movement of the actuator (8) with the desired motion profile and controlling movement of the actuator (8) based also on a comparison of the movement of the actuator (8) with the desired motion profile.

Abstract: A single-pole electrical connector includes an insulating sleeve and a retention ring positioned in the insulating sleeve. The retention ring defines an inner channel and a groove in a surface of the inner channel. The retention ring also includes a threaded hole intersecting the groove. A screw positioned in the threaded hole blocks the groove when in an extended position and leaves the groove unblocked when in a retracted position. A contact positioned in the inner channel includes a drive pin positioned in the groove. The contact is secured within the insulating sleeve when the screw is in the extended position and movable relative to the insulating sleeve when the screw is in the retracted position.

Abstract: A constant current regulator that receives an AC input current from a source provides a constant AC current to a load. The regulator includes first, second, third, and fourth electronically controllable switches, a transformer coupled to the switches, and a controller connected to the switches. An output of the first switch is electrically connected to an input of the second switch and one input of the transformer primary winding. An output of the third switch is electrically connected to an input of the fourth switch and another input of the transformer primary winding. The controller provides a trigger signal to each of the switches. The controller adjusts a duty cycle of the trigger signals based on a comparison between an actual current value and a reference current value to provide a constant AC current to the load.

Abstract: In a power distribution system, synchronizing switchgear operations with an AC voltage or current waveform can be accomplished more precisely with a closed-loop feedback, microprocessor-based motion control design. By employing a closed-loop feedback, microprocessor-based design, switchgear contact position and velocity can be monitored and optimized in real time during a switching operation, thereby assuring a more accurate switching operation. Moreover, the closed-loop feedback design intrinsically compensates for the effects of such things as ambient temperature, AC waveform fluctuations, and changes in the physical condition of the switchgear. The closed-loop position feedback design is also capable of optimizing various transfer function parameters associated with the closed-loop feedback process, both during and subsequent to a switching operation, to further assure that switching operations are more accurately synchronized with the AC voltage or current waveforms.

Abstract: A fuse includes a housing having first and second ends and an outer diameter of about 3 mm. The fuse further includes a nonconductive core arranged inside the housing and a fuse element wound spirally around the nonconductive core. An end cap is mounted on each of the first and second ends of the housing and each end of the fuse element is connected to a respective end cap. The fuse is rated at approximately 350 mA and 600 volts direct current and can withstand 100 pulses of 14 peak amps on {fraction (10/1000)} wave form without damage. The fuse element is wound on the nonconductive core at about 120 to 150 turns per inch, and the fuse element is a Cu/Ag wire having a diameter of about 0.002 inches.

Abstract: A transformer is disclosed, including a tank housing a transformer core/coil assembly, a dielectric insulating fluid surrounding the core/coil assembly, the fluid comprising a vegetable oil, an antioxidant dissolved in the oil, and a low temperature additive blended into the oil, wherein the fluid defines a headspace above the fluid. The preferred embodiment includes an oxygen absorbing material contained in the tank and in contact with gases in the tank but isolated from contact with the dielectric fluid, the tank including an opening and a sealed plug in the opening, such that the oxygen absorbing material can be replaced through the opening upon removal of the sealed plug, and further includes a gas permeable polymer container sealed against the opening for supporting the oxygen absorbing material and an indicator in gas contact with the headspace and visible from outside the tank for indicating the presence of oxygen in the headspace.

Abstract: An adjustable and releasable fastener for a pivoting hand tool includes a first bushing and a second bushing which are press fit in respective tool elements, the second bushing extending into a hole in the first bushing to form a pivot bearing. The first bushing includes a cap with a recess having a slotted opening connecting to the hole in the first bushing. A bolt is extends through the first and second bushings, with a bolt head disposed in the recess. A nut is fastened to a threaded end on the second bushing side. The nut can be tightened or loosened to adjust the tension on the bolt. The bolt head is shaped to allow it to pass through the slotted opening in the first bushing when the tool elements are pivoted beyond an operating range, permitting quick release of the tool elements.

Abstract: A portable electric soldering tool includes a housing forming a handle and a power head. A heating rod with a main and a secondary heating coil extends from the power head, the rod having an axial bore with a stainless steel lining to prevent solder from building up in the heating rod. A pump draws molten solder through the axial bore of the heating rod. A disposable solder collecting cartridge is removably mounted in the power head to collect solder drawn through the heating rod. The cartridge includes a barrel formed of a heat resistant plastic. Sealing gaskets are disposed at the open ends of the barrel, and a solder accumulator is disposed in the barrel to collect molten solder. The main and secondary heating coils are connected to a power switch. An electric motor for the pump is connected in series with the secondary heating coil. A selector switch energizes alternatively the main heating coil or the secondary heating coil and motor.

Abstract: A ceiling mounted, recessed, wallwash light fixture includes a reflector having an internal reflecting surface. A wallwash segment of that reflecting surface is defined by vertically adjacent reflecting faces each arranged so that an effective lowest point of brightness seen by the reflecting face is reflected along a line passing below an opposing portion of a bottom edge of the reflector. The wallwash segment can be defined by an insert attached to the reflecting surface.