Finding a short or leakage to ground in an appliance (meter and megohmmeter)
Leakage from a heater, motor, pump or wet harness to the metal frame is the usual reason appliances trip GFCIs. A standard meter finds hard shorts; a megohmmeter applies a higher test voltage and finds weak insulation that only leaks under real voltage, heat or moisture.
Cross-checked ~45 min moderateBrands: All
Before you start
- All tests are done with the appliance unplugged or the breaker off and verified dead
- A megohmmeter outputs high test voltage: do not touch the leads or the part during the test, and discharge the part afterwards
- Disconnect electronic boards and sensors from the circuit under test; insulation testers can damage electronics
Diagnostic steps
Unlock all 7 steps with expected values
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