Examining the causes of high motor current
The most frequent concern about a motor with high current is high no-load current with a 3-phase motor. That topic has been addressed in three prior Currents articles beginning with “Test Run Tips: Common Causes For High No-Load Current On Rewound Motors” (June 2002); “Avoiding High No-Load Amps On Rewound Motors” (February 2004); and “Taming Those Misbehaving Motors” (December 2009). This article will cover the broad topic of high no-load current with 3-phase motors and the issue of high current with load with 3-phase motors. Also considered will be cases of lower than expected no-load current.