Series transformers electronic switch - uses digital circuits driving triacs to energise transformers used to regulate line voltage in discharge lamp supplies

摘要

Voltage regulation of a line feeding discharge type lamps is obtained by placing transformers in the line feeding the lamps and energising one or more of the transformers to boost the voltage to levels manually set (3) in a nominated sequence which is controlled by a multi-contact clock (4). The set data is passed to a binary comparator (5) whose other input is from a shift register (7) with up-down shift controlled by a J-K flip-flop (8) switched by the binary comparator (5) output. A zero crossing circuit (11) controls the J-K flip flop (8) so the output triacs (14) which energise the appropriate transformer primary do not generate radio frequency interference.