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Part 4 - Diagnosis and T
roubleshooting
4.13.5 First troubleshooting step
To troubleshoot XP6 errors, first ensure that the DC bus wire is connected correctly. The DC bus wire should run from
the N terminal on the inverter module, through the current sensor (in the direction indicated by the arrow on the
current sensor), and end at the N terminal on the DC filter board.
Figure 4-4.3: DC detection wire connection method
DC bus wire
Current sensor
Inverter module N terminal
DC filter board N termianl
4.13.6 xL0 troubleshooting
Step 1: Check compressor
Check that compressor wiring is all connected properly.
The normal resistances of the inverter compressor are 0.7-1.5Ω among U V W and infinite between each of U V W
and ground. If any of the resistances differ from these specifications, the compressor has malfunctioned.
Figure 4-4.4: Measuring resistances among compressor
terminals
Figure 4-4.5: Measuring resistances between compressor terminals
and ground
If the resistances are normal, go to Step 2.
Step 2: Check inverter module
The DC voltage between terminals P1 and N1 should be 1.41 times the local power supply voltage. The DC
voltage between terminals P and N should be 537-586V (power supply voltage specification:380~415V 3N~). If
either voltage is not in the normal range, troubleshoot as for xL1 or xL2 errors. Refer to Part 4, 4.13.7 “xL1/xL4
troubleshooting” or Part 4, 4.13.8 “xL2 troubleshooting”.
Disconnect the terminals U, N, W from the inverter compressor. Measure the resistance among terminals P, N, U, V,
W. All the resistances should be infinite. If any of them are not infinite, the inverter module is damaged and should
be replaced.
