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STANDARD PdMA TEST SUITE

bulletResistance to Ground - Parameters are obtained with either 500 VDC or 1000 VDC.  All readings are temperature corrected and standardized to ensure precise trending of insulation condition.
 
bulletCapacitance to Ground - This parameter capitalizes on the natural capacitance of the motor and circuit to trend dirt and moisture build-up on the insulation. It is utilized in combination with the resistance to ground measurements to determine overall insulation condition.
 
bulletPhase Resistance - Extremely accurate phase-to-phase resistance values on the micro-ohm level are recorded to determine the quality of connections in the circuit and motor itself. An imbalance figure is then calculated for ease of interpretation and trending. Stator faults, both turn-to-turn and phase-to-phase, may be detected using these parameters.
 
bulletPhase Inductance - Once again, phase-to-phase inductance parameters are collected and an imbalance calculated to help determine rotor, stator and air gap health. Higher or escalating imbalances indicate the presence of an anomaly. Additionally, these parameters can be beneficial in identifying faulty capacitors within the circuit.

ADDITIONAL PdMA TESTS

bulletPolarization Index (PI) and
Dielectric Absortion Ratio (DAR) Utilizing detailed graphing and complete automation, the PI and DAR are used as advanced methods of evaluating insulation and can be highly effective at detecting the presence of contamination. Caution and alarm levels are set in accordance with IEEE specifications. The DAR applies a steady potential to the circuit for one minute, graphing results every 5 seconds and calculating a ratio of the reading at 60 seconds to that of 30 seconds. The Polarization Index (PI) is conducted in identical fashion, with the ratio calculated using the reading at 10 minutes compared to the one recorded at 1 minute.
 
bulletRotor Influence Check (RIC) -  The RIC is a test that examines the relationship between the rotor and stator fields. The rotor is incrementally rotated through one pole face, recording phase inductance at each position. The generated patterns are combined with standard test results to confirm the presence of rotor, stator and air gap problems. The collected parameters are sensitive enough to detect excessive porosity in cast rotors, cracked or broken rotor bars, or other defective conditions.