Adopting 2 types of motors within electric actuators, one type with property of low noise and safety which doesn't need to provide power for long time service so that saving energy. The other type is single direction motor combines with spring return device, valve can be automatically closed when lose power. Both of upper 2 types of actuators can be manually operated by level. Besides, main valve material is made by copper alloy can prevent corrosion and with stable quality which reduces leakage happened and increases system running efficiency.