Motors: The Proactive Approach To Voltage Unbalance
Once we distinguish voltage unbalance from voltage variation, the need to tackle the issue intelligently becomes even more clear. Learn about common causes and effects, testing for unbalanced voltages and single-phasing, and ways to correct the problem if it does manage to arise.
It’s impossible to balance line-to-line voltages perfectly in three-phase circuits, so they typically differ by a few volts or more. However, if voltage unbalance exceeds 1%, it can markedly decrease the performance and energy efficiency of three-phase motors while increasing the likelihood of premature failure. Avoiding these issues requires a proactive approach that includes installing adequate protective devices and periodically checking for voltage unbalance at the motor terminals.