8. Grounded Windings
Test the compressor motor for a grounded winding. The check should be made using an
ohmmeter capable of measuring very high resistance on a VOM. The resistance
between windings and the housing is one million to three million ohms for an
ungrounded winding.
Attach on lead to the compressor case on a bare metal tube and to each compressor
terminal as shown in Figure 41. A short circuit at a high voltage indicates a motor defect.
9.
Compressor not pumping.
Connect gage block hoses to the suction and discharge pressure ports in the
compressor unit. Read pressure gages to affirm that system is pressurized with
refrigerant. Turn on power to compressor unit and run unit. Observe pressure gages. If
pressures on both gages remain the same, compressor is not pumping and there is a
possible internal failure. See Troubleshooting Chart.
SD-410-QS (H) (06/15)
Figure 41. Compressor Motor Grounded Winding Test
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