Carrier QHC Series Service Manual page 48


IPM continuity check
Turn off the power, let the large capacity electrolytic capacitors discharge completely, and dismount the IPM. Use a digital
tester to measure the resistance between P and UVWN; UVW and N.
Digital tester
(+)Red (-)Black
N
U
P
V
W
Normal resistance value
∞
(Several MΩ)
Digital tester
(+)Red (-)Black
U
V
N
W
(+)Red
46
Normal resistance value
∞
(Several MΩ)