Abstract: There are apparatus and methods for generating a plurality of voltage levels. There is a rotor that includes a first and a second portion of rotor windings. The first portion of rotor windings is constructed and arranged to establish a first magnetic field of a first number of poles. The second portion of rotor windings is constructed and arranged to establish a second magnetic field of a second number of poles. A stator is disposed adjacent the rotor. The stator includes a first and a second portion of stator windings. The first portion of stator windings is related to the first number of poles and has a first output port configured for furnishing an electrical output at a first voltage level. The second portion of stator windings is related to the second number of poles and has a second output port configured for furnishing an electrical output at a second voltage level.

Abstract: There are apparatus and methods for generating a plurality of voltage levels. There is a rotor that includes a first and a second portion of rotor windings. The first portion of rotor windings is constructed and arranged to establish a first magnetic field of a first number of poles. The second portion of rotor windings is constructed and arranged to establish a second magnetic field of a second number of poles. A stator is disposed adjacent the rotor. The stator includes a first and a second portion of stator windings. The first portion of stator windings is related to the first number of poles and has a first output port configured for furnishing an electrical output at a first voltage level. The second portion of stator windings is related to the second number of poles and has a second output port configured for furnishing an electrical output at a second voltage level.

Abstract: A ground fault detector has a neon bulb connected between a rectangular copper plate connected to an antenna wire and a resistor connected to one arm of a double-pole double-throw relay with the stationary contacts cross coupled to hot and neutral wires of a three-wire A.C. line. A photocell detector is optically coupled to the neon bulb and provides a signal to a live wire detector circuit when the neon bulb is illuminated to disable operation of the relay. A timer circuit causes the live wire detector circuit to operate the relay when the neon bulb is not illuminated after a predetermined time. A network is photo-optically coupled to a ground status detector that controls a contactor that selectively connects power to the equipment being monitored. The junction of a Y network is also coupled to the input of the ground status detector. The input of the photo-optical coupler is connected between a leg of the Y circuit and the enclosure of the equipment being monitored.

Abstract: An apparatus for energizing a fluorescent lamp having two filament electrodes. The apparatus comprises a rectifier circuit responsive to an AC voltage for providing DC voltage and a transformer having at least a primary winding and a secondary winding for providing transformed power to said lamp. A switch intermittently connects said DC voltage to said primary winding to develop current pulses at an ultrasonic frequency. Said secondary winding is coupled to said filament electrodes to both heat said filament electrodes and establish a potential thereacross for initiating and maintaining an arc therebetween.

Abstract: A rail-support insulating device for electrically insulating a rapid transit rail and rail fastener from the rail support structure is described. The device includes an electrically non-conductive member that surrounds and extends outwardly from the rail fastener and over its support structure. Also a pair of planar disc members of similar material extend around and outwardly from the heads of the mounting bolts for the rail fastener, thereby forming long surface electrical creepage paths between the rail and the rail support that provide electrical isolation even when the entire assembly of rail fastener and rail support is wet with electrolyte.

Abstract: A generally figure-of-eight transformer core carries first, second and third toroidal windings spaced along its central leg and is formed with magnetic shunts across the gaps between central and outside legs in the planes between windings. A capacitor is connected across the second winding of value so that it coacts with the effective leakage reactances provided by the magnetic shunts so that the output load current provided by the third winding is directly proportional to the input voltage applied across the first winding independently of the load impedance and with low distortion, even in the presence of high harmonic content in the input voltage and a nonlinear load impedance.