Circuit arrangements or apparatus for igniting or operating discharge lamps

HELECTRICITY H05Electric techniques H05BELECTRIC HEATING ELECTRIC LIGHTING NOT OTHERWISE PROVIDED FOR

H05B41/00Circuit arrangements or apparatus for igniting or operating discharge lamps

H05B41/02Details H05B41/04Starting switches H05B41/042using semiconductor devices H05B41/044for lamp provided with pre-heating electrodes H05B41/046using controlled semiconductor devices H05B41/048using electromagnetic relays H05B41/06thermal only H05B41/08heated by glow discharge H05B41/10magnetic only H05B41/12combined thermal and magnetic H05B41/14Circuit arrangements H05B41/16in which the lamp is fed by dc or by low-frequency ac H05B41/18having a starting switch H05B41/19for lamps having an auxiliary starting electrode H05B41/20having no starting switch H05B41/22for lamps having an auxiliary starting electrode H05B41/23for lamps not having an auxiliary starting electrode H05B41/231for high-pressure lamps H05B41/232for low-pressure lamps H05B41/2325provided with pre-heating electrodes H05B41/233using resonance circuitry H05B41/234to eliminate stroboscopic effects H05B41/24in which the lamp is fed by high frequency ac, or with separate oscillator frequency H05B41/245for a plurality of lamps H05B41/26in which the lamp is fed by power derived from dc by means of a converter H05B41/28using static converters H05B41/2806with semiconductor devices and specially adapted for lamps without electrodes in the vessel H05B41/2813Arrangements for protecting lamps or circuits against abnormal operating conditions H05B41/282With semiconductor devices H05B41/2821by means of a single-switch converter or a parallel push-pull converter in the final stage H05B41/2822using specially adapted components in the load circuit H05B41/2824using control circuits for the switching element H05B41/2825by means of a bridge converter in the final stage H05B41/2827using specially adapted components in the load circuit H05B41/2828using control circuits for the switching elements H05B41/285Arrangements for protecting lamps or circuits against abnormal operating conditions H05B41/2851for protecting the circuit against abnormal operating conditions H05B41/2853against abnormal power supply conditions H05B41/2855against abnormal lamp operating conditions H05B41/2856against internal abnormal circuit conditions H05B41/2858for protecting the lamp against abnormal operating conditons H05B41/288with semiconductor devices and specially adapted for lamps without preheating electrodes H05B41/2881Load circuits; Control thereof H05B41/2882the control resulting from an action on the static converter H05B41/2883the controlled element being a DC/AC converter in the final stage H05B41/2885Static converters especially adapted therefor; Control thereof H05B41/2886comprising a controllable preconditioner H05B41/2887characterised by a controllable bridge in the final stage H05B41/2888the bridge being commutated at low frequency H05B41/292Arrangements for protecting lamps or circuits against abnormal operating conditions H05B41/2921for protecting the circuit against abnormal operating conditions H05B41/2923against abnormal power supply conditions H05B41/2925against abnormal lamp operating conditions H05B41/2926against internal abnormal circuit conditions H05B41/2928for protecting the lamp against abnormal operating conditions H05B41/295with semiconductor devices and specially adapted for lamps with preheating electrodes H05B41/298Arrangements for protecting lamps or circuits against abnormal operating conditions H05B41/2981for protecting the circuit against abnormal operating conditions H05B41/2983against abnormal power supply conditions H05B41/2985against abnormal lamp operating conditions H05B41/2986against internal abnormal circuit conditions H05B41/2988for protecting the lamp against abnormal operating conditions H05B41/30in which the lamp is fed by pulses H05B41/32for single flash operation H05B41/325by measuring the incident light H05B41/34to provide a sequence of flashes H05B41/36Controlling H05B41/38Controlling the intensity of light H05B41/382during the transitional start-up phase H05B41/384in case of hot-restriking H05B41/386for speeding-up the lighting-up H05B41/388for a transition from glow to arc H05B41/39continuously H05B41/391using saturable magnetic devices H05B41/392using semiconductor devices H05B41/3921with possibility of light intensity variations H05B41/3922and measurement of the incident light H05B41/3924by phase control H05B41/3925by frequency variation H05B41/3927by pulse width modulation H05B41/3928for high-pressure lamps H05B41/40discontinuously H05B41/42in two steps only H05B41/44for providing special optical effects H05B41/46Circuits providing for substitution in case of failure of the lamp