Bi-level ballast circuit for operating HID lamps
July 6, 2008. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3662216 3679932 Wattage reducing device for fluorescent fixtures Discharge lamp energization circuit, particularly for audio and supersonic frequency operation of high-pressure discharge lamps Power supply for low-voltage incandescent lamp and like load Power supply for low voltage incandescent lamp Lamp dimmer Capacitively ballasted low voltage incandescent lamp Capacitively ballasted low voltage incandescent lamp Starting and dimming circuit for fluorescent lamps InventorAssigneeApplicationNo. 215605 filed on 07/06/1988US Classes:315/240, Electric switch in the condenser circuit315/239, Transformer in the condenser load device circuit315/291CURRENT AND/OR VOLTAGE REGULATIONExaminersPrimary: LaRoche, Eugene R.Attorney, Agent or FirmInternational ClassH05B 041/42AbstractA bi-level ballast network is disclosed for operating an HID lamp at either a low power or standby level and at a high power or full light level. The network includes an unswitched capacitor connected to the transformer ballast coil and a switched capacitor connected to a solid state relay (SSR) circuit, the electronic components providing the switching therein being back-to-back SCR's. When the SSR is operated the contacts connected to the switched capacitor open or close at the next subsequent zero crossing of the applied ac source voltage. This changes the capacitance of the network to increase the power to the lamp or decrease the power thereto depending on the operating condition prior to the SSR being operated. Current, voltage and dvdt protection devices are also provided.Field of SearchPeriodic switch in the supply circuitCondenser in the supply circuit PERIODIC SWITCH IN THE SUPPLY CIRCUIT Plural periodic switches or multiple contact periodic switch CONDENSER IN THE SUPPLY CIRCUIT Plural series connected condenser and load device circuits Electric switch in the condenser circuit Transformer in the supply circuit Inductance in the condenser circuit Transformer in the condenser load device circuit CURRENT AND/OR VOLTAGE REGULATION Variable impedance-type regulator Condenser in one of the supply circuits | |
