Pioneer QUANTUM INVERTER Series Service & Troubleshooting Manual page 147

8.3 IPM Continuity Check
WARNING
Electricity remains in capacitors even when the power supply is off.
Ensure the capacitors are fully discharged before troubleshooting.
1. Turn off outdoor unit and disconnect power supply.
2. Discharge electrolytic capacitors and ensure all energy-storage unit has been discharged.
3. Disassemble outdoor PCB or disassemble IPM board.
4. Measure the resistance value between P and U(V, W, N); U(V, W) and N.
Digital tester
(+)Red (-)Black
P
Note: The picture and the value are only for reference, actual condition and specific value may vary.
Resistance value
N
∞
U
(Several MΩ)
V
W
Troubleshooting

Digital tester
(+)Red (-)Black
U
V
N
W
-
39
Resistance value
∞
(Several MΩ)