CONTROLLING START-UP OF ELECTRICALLY-POWERED EQUIPMENT SUCH AS A COMPRESSOR

摘要

A method and device to control start-up of three-phase electrically-powered equipment such as a compressor having a drive output rotor shaft to avoid mechanical damage. The device is used to detect and measure rotor shaft speed during start-up to produce an output signal and feeding that output signal to an actuating means arranged to abort start-up in the event of failure of the rotor shaft to attain a specified speed, preferably if it has not been reached within a specified time. Particular application is in star/delta starting of high starting load/torque electrical motors.