Motor energy-saving protection device

The utility model relates to a motor energy-saving protection device which controls the center or three corners conversion of three-phase AC motor in the operation process. The utility model consists of a comparator which is used for comparing the sampling circuit of motor line current with the sampling signal, a time relaying circuit and an electric switch. The utility model is characterized in that a conversion time relay circuit and a starting relay circuit are added. The electric switch is connected with the conversion time relay circuit and the starting relay circuit. The utility model is also provided with a pilot lamp display circuit. The utility model has the advantages of strong interference resistance, relative stable operation of the motor, relative strong adaptability and being convenient for adjusting.