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Power Circuit: What and Why?

Noah Bethel | Vice President-Product Development, PdMA Corporation

Power Circuit: What and Why?

Power Circuit = Voltage Delivery

The power circuit provides the avenue or path that allows your supply voltage to reach the motor. The power circuit comprises all the cabling, connectors, switches, contacts, and terminal blocks from the transformer power supply to the motor leads. These connections are under constant mechanical, thermal, electrical, and environmental stresses, presenting plenty of opportunity for a compromised power circuit. And a compromised power circuit will result in an inefficient and unreliable motor as a result of voltage and current imbalance, localized heating of a bad connection, and excessive internal heating of your electric motor and insulation systems.

Power circuit testing with the motor de-energized can be performed with the MCE® phase-to-phase resistance measurement and trended with a resistive imbalance calculation. Remember to include as much of the power circuit as safely possible. If the motor is energized the EMAX Power test provides voltage and current measurements and imbalance calculations to identify any power circuit anomalies. Remember voltage imbalance is only seen if your voltage leads are downstream of the fault.

To see the MCEMAX® used to identify a power circuit anomaly, visit the PdMA YouTube channel at:

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About the Author

Noah Bethel Vice President-Product Development, PdMA Corporation

Noah has over twenty-five years of broad operations and electrical systems maintenance experience in industrial, commercial, and military settings ranging from nuclear submarines to world class amusement parks. His experience includes high and low voltage, AC and DC, power generation, power distribution, motors, and motor controllers. Noah is currently in charge of product development for new and existing PdM technology at PdMA Corporation.

Noah is a graduate of the University of the State of New York and the Naval Nuclear Power School and Training Unit. He is a Certified Maintenance Reliability Professional, with field experience in motor circuit analysis, current signature, power analysis, thermography, vibration analysis, oil analysis and ultrasonic testing.