Page 61 - Basic PD Theory
P. 61
Off-line Testing
Side Clearance Measure interference fit Checks for coil tightness Fail: > 0.125mm for a length QA test
Check with a gauge more than 15-20cm (epoxy)
or 0.5mm (asphalt)
Surge Test Measure response to Tests turn-to-turn Good manufacturing test. Factory and Repair Shop Potentially destructive IEEE 522
impulse voltages insulation Stress on line-end coils
Winding Resistance Measure with low Detects poor connections Effective for trending, use 1-1.5
resistance ohm meter or shorted strands Kelvin Bridge Maintenance test
Wedge Tap test Tap wedges with Tests wedge security for Looseness by feel or QA test
calibrated hammer loose coils/bars virbration
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