Abstract: The electrical control line should have the consummation protection link, with protects the electrical network, the electric motor, controls the electric appliance as well as other circuit element, eliminates when the normal work the harmful influence, avoids because of the misoperation having the accident.The commonly used protection link has the short circuit, the overflow, the overload, has pressed, loses presses, the weak magnetism, overspeed and the limit protection and so on.
Key word: Electric motor choice; Low pressure electric appliance; Relay; Fuse; Protects the link.