MQ3 series dual power automatic transfer switches (follow brief as setting) is one of adopted international technology developed by our company. The setting is suits for AC 50Hz, rated working voltage is 400V, rated current 6A-100A and under dual power supply system. It has over voltage, under voltage, lost phases protection function. The setting mainly used for hospital, shopping center, bank, and chemical industry, metallurgy, high building, military facilities.