METHOD OF OPERATING AT LEAST ONE FLUORESCENT LAMP WITH ELECTRONIC BALLAST AND AND BALLAST THEREFOR 0002 FIELD OF THE INVENTION 0003 The present invention relates to a method of operating at least one fluorescent lamp using an electronic ballast,

摘要

The present invention relates to a method and a ballast for operating at least one fluorescent lamp using an electronic ballast. The present invention relates to a method and a ballast for operating at least one fluorescent lamp (FL) using an electronic ballast. The control circuits CCO, SEL, V2, V3 of the rectifying bridge GL across which the AC main voltage crosses, the incremental converters L1, D1, V1, the half bridge circuits V2, V3 connected to the power transistors V2, V3, A control loop (IC) is provided for continuously monitoring the lamp current by means of a control circuit (HSD, LSD), which maintains a constant lamp current during normal operation. Timers (PST, IT, CT) that are started each time the lamp is started or an obstacle is detected are set to predetermined reference levels (Mp, Mi and Mo) that vary as individual time segments ( Tt, Iit, St, (CCO, IST, SEL, HSD, LSD) as a function of time when evaluating the instantaneous lamp current and triggering the automatic disconnection of the electronic ballast in the event of a normal start or defect of the lamp To generate a time base for the monitoring circuit (MON) to control the current.