Inductive ballast on a metal-vapour discharge lamp, especially for mercury-vapour discharge lamps

摘要

In the case of the ballast (10), which is particularly suitable for mercury-vapour discharge lamps (11), a flyback converter (17), which is supplied with direct current on the primary side and has an operating frequency of more than 1 kHz, is provided, whose secondary side is coupled to electrodes (12, 13) of the lamp (11), means (30) being provided for changing the duration of the control pulses of the flyback converter (17). In consequence, it is possible to vary the brightness of the burning lamp (11) virtually continuously within wide limits. IMAGE