Series relay single-phase voltage stabilizers, adopting the double sampling, double stabilizing voltage, and the advanced electronic automatic controller, which employs the time-base IC for time-delay, offer the advantages of quick work, accurate timing, steady performance, safety and electricity-saving, excellent design, reasonable construction, easy operation, wide input voltage range, etc, The voltage stabilizers are the universal protectors in the high-grade household appliances, such as refrigerator, television, and so on. Service Occasions Computer, testing equipment, lighting system, safety alarm system, ray system, communication system, medical equipment, copier, stereo sound equipment, industrial unattended equipment, color developing and printing equipment, numerical control machine, inspection machine, television, office equipment.