SOURCE OF SECONDARY POWER SUPPLY Russian patent published in 1994 - IPC

FIELD: radio engineering. SUBSTANCE: invention may find use as A.C./D. C. converter in electric and radio equipment. Source of secondary power supply includes capacitive ballast 1, stabilized rectifier unit 3 and protection device 2 connected in series between them. Protection device of source has first stage of protection which includes safety fuse and threshold circuits of closure of phase wire to common wire and second stage composed of power supply circuit of relay which contacts in initial state are closed to load and provide for break of phase and common wires ahead of stabilized rectifier unit. EFFECT: enhanced reliability and safety with use of source without transformer, ensured isolation of primary power supply circuit from secondary one and load in case emergency. 1 dwg