Main task

A high-voltage pulse is required to light the bulb and initiate discharge. This high-voltage pulse is generated in the ignition transformer (663a), which also functions as a bulb socket. The high-voltage pulse can normally reach about 23,000 V. When the bulb is removed, the high-voltage pulse can reach 30,000 V. Once discharge has been initiated by the high-voltage pulse, power is supplied to the bulb by the ballast (663b).