Motor restarting technology is one of the power supply system after the failure of remedial measures, choosing the best restarting method and technology to appropriating the enterprise is the key to improve the reliability of power supply and distribution system of enterprise.The technique principles four motor restarts including the no controlled restart were introduced from the power supply system of fault types,and the advantages and disadvantages of the reliability, failure rate, investment and implementation perspective were analyzed. Taking a petrochemical ethylene plant as an example, the technical of the motor restart and specific restart configuration the plant currently employed were introduced, and the voltage drop starting with infinite power system motor calculation method to verify the restart capacity allocation was reasonable, which could provide reference for the selection and configuration of the same type enterprises starting in the motor.