Abstract: A method for bringing a predetermined turn of a coil located inside the width of the coil and beneath at least one layer of the coil and a coil made by such method.

Abstract: A method for a loop of a predetermined turn of a coil located inside the width of the coil and beneath at least one layer of the coil.

Abstract: A transformer in which the primary coil and the secondary coil are insulated from the iron laminations which form part of its flux paths by insulated covers which snap-on to the primary and secondary coils.

Abstract: A ballast for lighting an auxiliary source of illumination whenever a primary source of illumination fails to ignite. The auxiliary source of illumination is effectively turned OFF by placing a short circuit thereacross whenever the primary source of illumination is lit. The short circuit is removed whenever the primary source of illumination fails to reach a predetermined level of illumination thereby permitting current to flow through and light the auxiliary source of light. The ballast also includes a power factor correction device for increasing the ballast power factor when the primary source of light reaches a predetermined level of illumination.

Abstract: An arrangement for use with gaseous discharge lamp circuits having a power factor capacitor in which the capacitor can be disconnected from the circuit when the lamp is not drawing current and in which an emergency lamp can be connected across a voltage source when the discharge lamp is not drawing current.

Abstract: A starting and operating circuit for a discharge lamp in which the ballast reactance includes first, second and third coil segments with the third coil segment comprising part of the ignitor circuit and being electrically connected between the first and second coil segments.

Abstract: Control equipment for motors having two windings and wherein both windings are temporarily connected in parallel to start the motor.

Abstract: An arrangement for use with gaseous discharge lamp circuits having power factor capacitors in which the capacitor is disconnected from the circuit when the lamp is not drawing current.

Abstract: A starting and operating circuit for a discharge lamp in which the ballast reactance includes first, second and third coil segments with the third coil segment comprising part of the ignitor circuit and being electrically connected between the first and second coil segments.

Abstract: A starting and operating circuit for a discharge lamp in which the ballast reactance includes first, second and third coil segments with the third coil segment comprising part of the ignitor circuit and being electrically connected between the first and second coil segments.

Abstract: An ignitor or starting circuit for a high pressure arc discharge lamp including a voltage sensitive bidirectional switch and an impedance with a resistor and inductor in series circuit. An additional capacitor is connected in parallel across the voltage sensitive switch and the resistor.

Abstract: A starting and operating circuit for a discharge lamp in which the ballast reactance includes first, second and third coil segments with the third coil segment compromising part of the ignitor circuit and being electrically connected between the first and second coil segments.

Abstract: A hybrid ballast apparatus for starting and operating a plurality of series-connected discharge lamps and which provides protection against electric shock. The ballast apparatus includes first and second bidirectional thyristors connected in parallel with first and second ones of said lamps, respectively, and a trigger control circuit for simultaneously triggering the thyristors into conduction. Each lamp has two filaments and means are provided for connecting an L-C ballast device, the lamp filaments and the first and second thyristors in a series circuit across the AC supply voltage terminals. If one end of a lamp is removed from its socket, the series circuit is opened so that the maximum voltage at any lamp electrodes is limited to the AC supply voltage.

Abstract: A thermal protection device for a dual input voltage lighting fixture apparatus which includes a reversible connector for coupling either of two possible input voltages to the appropriate terminal of a winding of a transformer/ballast apparatus via a normally closed contact of a heat responsive thermal switch having a heating element electrically coupled to the reversible connector and thermally coupled to the closed contact. The latter contact opens in response to a level of heat above a given value. The transformer winding has two connection terminals, one of which is a tap point, connected to the reversible connector. The connection scheme provides the same energizing voltage to the heating element for each of the two different possible levels of the input voltage. The apparatus will automatically indicate if the connector is reverse connected for either of the two input voltages.

Abstract: A ballast circuit for starting and operating a preheat type circular fluorescent lamp, which replaces a multiple wattage incandescent lamp in a three-way incandescent lamp socket, so that the fluorescent lamp can be ignited to function at three different operating wattages. A lamination stacked core structure mounts first and second coils. A passive circuit element, such as positive temperature coefficient resistor also known as a thermistor, is connected in the circuit, which includes a three-way incandescent lamp screw base, for current switching functions to achieve the desired ignition and operating currents for the fluorescent lamp at its different operating wattages.

Abstract: A discharge lamp ballast circuit comprises at least one discharge lamp connected in series circuit with a ballast capacitor and inductor across a pair of input terminals for a source of A.C. supply voltage. A controlled semiconductor switching element is coupled across the lamp electrodes and a control circuit for the switching element is coupled to the input terminals and to a control electrode of the switching element. A voltage dependent non-linear impedance device is connected in shunt with the capacitor so as to limit the capacitor voltage to a predetermined value. The voltage dependent impedance device prevents the occurrence of hazardous voltage levels in the circuit and improves the stability during the warm up phase.