Megohmmeters, clearing up many misconceptions.

1 Never use a Megohm (hipot) test in a vacuum

2 Scroll compressors can be perfectly good as low as . 5 megohms yet some meters show them bad at 20 megohms.

3 General megohm readings for open motors not sealed motors in a Refrigerant environments.

4 Contamination of moisture and acids is more likely a cause of low Megohm. readings. this can be solved by a cleanup process.

5 A megohmmeter with a selectable voltage range and digital readout should be used over a period of time to show trends and possible contamination. example Fluke 1503

6 Refrigerant, oils and quantities can affect the readings. also anything else connected to the circuit during testing.

7 See Emerson Copeland AE bulletin 1294 for more information.

How many good compressors have been condemned?