What is a motor starting reactor?
A motor starting reactor is basically a form of inductor specifically designed for a particular motor situation to eliminate torque damage, reduce voltage drop and “cushion” the start of an AC motor. Since the 3 phase induction motors can draw up to 600% of rated line current when starting, the use of a proper reactor adds to the life of the motor and usually everything connected to it. Marelco motor starting reactors are made with six taps in line permitting selection of a range of starting voltages from 50% to 85% of full line voltage. A time set relay is used to delay the application of full voltage. This, the reactor is on line during the startup period only and consumes no power under continuous operation when the motor is at normal speed. Motors with severe service such as “inching and jogging” require larger capacity reactors depending on the equivalent of the reactor’s duty rating.
