AUTOMATIC MOTOR TESTING METHOD AND APPARATUS

摘要

A method and apparatus for testing the starting torque of electric motors includes attaching a flywheel of known diameter and weight to the motor's shaft along with an incremental encoder and measuring the amount of shaft rotation during known time intervals. A counter receives the output pulses from the encoder and a data latch captures the value of the counter at regular time intervals, such as once or twice during a cycle of an alternating current power line or upon zero crossing of the current to the motor. The count for each interval is retained in computer memory and later compared with a previous count to indicate changes in RPM from one interval to another. The change in RPM is a function of torque and can be plotted against motor speed, which is also calculated from the encoder output.