Fluorescent lamp igniting method, involves lowering operational frequency to pre-given frequency stage, if igniting signal does not exceed preset limiting value after expiry of delay time according to previous change of frequency

摘要

The method involves beginning an igniting period lowering an operational frequency of a supply voltage (V 2) supplying to a load. An igniting signal is monitored, and the frequency is increased if the igniting signal exceeds a preset limiting value. The frequency is lowered to a pre-given frequency stage, if the igniting signal does not exceed the limiting value after expiry of delay time according to a previous change of the frequency.