DEVICE FOR CONTROLLING MOTOR STARTUP AND PROTECTING METHOD THEREIN

PROBLEM TO BE SOLVED: To provide a device for controlling motor startup and a protecting method in starting the motor which solve the problem of wasteful consumption of energy or the like without causing a drastic cost increase to an entire system. SOLUTION: A device 10 for controlling a motor startup detects the temperature of each magnetic pole inside a motor starter 12 with an ambient temperature sensor 36 and magnetic pole temperature sensors 30, 32, 34. A microprocessor 28 connected to these sensors receives temperature signals periodically and monitors the change of the operating temperature of the motor starter. The microprocessor models the cooling characteristics of a motor starting system, and compares ambient temperature and the magnetic pole temperature signals being collected with the molded cooling characteristics to judge whether or not the motor starter has been cooled down to a safe starting temperature. Guaranteeing the motor starter not to exceed the maximum number of starts per hour, the controlling device inhibits such tries for a startup as not only waste energy but also further delay of the time until a successful startup.