Abstract: A HID dimming method and apparatus are provided. The method includes generating a dc waveform during a reduced power dimming mode of operation of the HID lamp, the reduced power dimming mode being less than the full power rating of the lamp, and driving the lamp with the dc waveform to generate a dimmed lamp output. An ac waveform may be utilized to drive the lamp during the full power mode of operation.

Abstract: An improved reactor and ballast system is provided. The reactor includes a core having an I portion and a rolled portion which forms a core opening, a coil having an electrically insulated coil opening through which the I portion extends, and a spacer between the I portion and an edge of the rolled portion of the core. A portion of the coil extends into the core opening. The ballast system includes a core having a plurality of I portions and a rolled portion which form one or more core openings, a plurality of coils, each coil having an electrically insulated coil opening through which one of the I portions extends, and a plurality of spacers between the I portions and a first edge of the rolled portion and between the I portions and a second edge of the rolled portion. A portion of each coil extends into a corresponding core opening.

Abstract: A ballast circuit with an ignitor circuit for starting serially connected HID lamps is provided. The ballast circuit comprises an electromagnetic ballast arrangement for driving the lamps and an ignitor circuit for starting the lamps. In an embodiment of the invention, the ignitor circuit comprises a voltage-breakover device, a first capacitor, a resister, a pulse autotransformer, and a second capacitor. A pulse autotransformer is associated with each subsequent lamp after a first lamp of the serially connected lamps.

Abstract: A metal halide gas discharge lamp comprises an arc tube containing a vaporizable metal halide and first and second spaced electrodes. An arrangement for heating the arc tube assists in creating an arc discharge between the first and second electrodes. It comprises a heat source positioned to heat the arc tube, and an electron barrier disposed between the heat source and the arc tube for minimizing accumulation of photoelectrons on an outer surface of the arc tube so as to substantially avoid sodium migration out of the arc tube. A switch deactivates the heat source after the arc tube is heated a desired amount.

Abstract: Included in a ballast circuit arrangement for a gas discharge lamp is a ballast transformer arrangement receptive of an input power signal and providing an output, ballast voltage. Further included is a pulse transformer having a secondary winding in serial circuit with the lamp for impressing a high voltage, hot restrike starting pulse across the lamp. A bypass capacitor is coupled to the ballast transformer for being charged by the ballast voltage. A hot restrike starting circuit for pulsing a primary winding of the pulse transformer comprises a serially connected starting capacitor and resistor coupled across the bypass capacitor; and a circuit for discharging the starting capacitor including, in serial circuit, the primary winding of the pulse transformer and a current switch having a control electrode responsive to a control signal.

Abstract: Disclosed is a ballast circuit arrangement for a gas discharge lamp, which includes a ballast transformer arrangement receptive of an input power signal, having a winding and a serially connected ballast capacitor, and providing an output, ballast voltage that alternates in polarity during successive half cycles. A bypass capacitor is coupled to the winding of the ballast transformer for being charged by the ballast voltage. A voltage for driving the lamp exists on the bypass capacitor. The inventive arrangement includes a pulse transformer having a secondary winding in serial circuit with the lamp for impressing a high voltage, hot restrike starting pulse across the lamp. A hot restrike starting circuit is provided, comprising a starting capacitor coupled across the bypass capacitor, and a circuit for discharging the starting capacitor including a primary winding of the pulse transformer and a serially connected current switch.

Abstract: A ballast circuit arrangement with hot restrike capabilities includes an input transformer having a primary winding receptive of line power and a secondary winding over which an output voltage is made available. A first capacitor coupled across the secondary winding of the input transformer develops a voltage charge thereon. A resistor and a second capacitor are series connected to one another and are parallel coupled across the first capacitor. A starting aid device is coupled to the secondary winding of the input transformer and produces an output voltage of a predetermined magnitude. The output voltage of the starting aid is coupled to a spark gap device having first, second and third electrodes associated therewith. A first spark gap formed between the second and third electrode is first fired by the output voltage of the starting aid which in turn triggers the firing of a second spark gap formed between the first and second electrodes.

Abstract: A sports lighting fixture having a broken glass detection arrangement includes a high intensity light source disposed near the closed end of a reflector member. A cover member made of a light transmissive material is disposed at the open end of the reflector and is effective for filtering UV radiation emitted by the light source. A ballast circuit has in input portion receptive of line power and an output portion effective for conditioning the line power to energize the light source. A conductor strip is disposed on the cover member and is effective such that, when the cover member is intact, an electrical signal can be passed therethrough.

Abstract: A control circuit is disclosed for appliances such as dishwashers and clothes washers. The control circuit employs a microprocessor programmed to respond to user selected options to determine the operating sequence of the appliance. The control circuit includes an overfill system which permits the microprocessor to detect and identify a flood condition in response to a signal from a float assembly. The flood signal causes the microprocessor to initiate a flood control routine which interrupts the normal operating cycle being executed, if any, and initiates and maintains operation of a drain cycle until the water returns to the normal level for a predetermined period of time. The flood routine overrides all other program control thereby preventing any other machine function until the flood condition has been eliminated and there has been user interaction. The user is advised of the flood condition via an alpha-numeric digital display on the appliance control panel.

Abstract: A control circuit is disclosed for appliances such as dishwashers and clothes washers. The control circuit employs a microprocessor programmed to respond to user selected options to determine the operating sequence of the appliance. Feedback systems permit the detection and indication of fault conditions, such as overfill or drain blockage, and initiate protective responses from the microprocessor to prevent flooding or damage to the appliance. The circuit includes a diagnostic system having a diagnostic routine which will sequence through the usual operating cycles in response to operator input and which may be advanced through the cycles at the operator's discretion. The operative cycles and applicance malfunctions, if any, are displayed on a control panel as the diagnostic routine is executed thereby facilitating diagnosis and repair.

Abstract: A control circuit is disclosed for appliances such as dishwashers and clothes washers. The control circuit employs a microprocessor programmed to respond to user selected options to determine the operating sequence of the appliance. The circuit includes a drain feedback system which permits the microprocessor to detect and identify a plurality of drain fault conditions including failure to drain, slow drain and plugged drain. A protective response is initiated by the microprocessor to prevent flooding or damage to the appliance should any of these fault conditions occur, and the user is advised of the specific fault mode via an alpha-numeric digital display on the appliance control panel. In the event a rapid drain occurs, the feedback system immediately terminates pump-out and transfers the time saved to a subsequent time-insensitive cycle, thereby eliminating undesirable operation of pump and motor while maintaining the total cycle time as originally programmed.

Abstract: A relay control circuit for controlling the operation of various electrically actuated devices in a washing appliance such as a dishwasher is disclosed. The circuit employs four relays to provide eight operating functions, including filling, draining, dispensing of additives, water circulation, water circulation with heat, and drying.