Hitachi UTOPIA RAS-4HVRP2E - Checking Procedeure for the DC Fan Motor

10 Troubleshooting
Checking procedure for main parts
SMGB0136 rev.0 - 07/2021
309
10
Check Point
Normal Range (V)
(+) Side of Tester (-) Side of Tester
P1
VDC-2
Approx. 311VDC
VCC15-1 13.5VDC ~ 16.5VDC
VCC05
GND1
4.5VDC ~ 5.5VDC
VCC12 11.9VDC ~14.3VDC
! CAUTION
• Donotapplythetestleadtounspeciedcheckpointswhenmeasuringthevoltagewithacircuittester.Otherwise,itmaycausea
failure of the outdoor unit PCB and the circuit tester.
• When measuring the voltage with a circuit tester, the setting of the circuit tester shall be set within the DC voltage measurement range.
If the setting is not correct, it may cause a failure of the outdoor unit PCB and circuit tester
10.4.1.2 Checking procedeure for the DC fan motor
When ISPM/DIP-IPM is faulty and Alarm 03, 04 or 53 appears, the fan motor may also be damaged. To prevent ISPM/
DIP-IPM damage which may result from operation combined with a faulty fan motor, check also if the fan motor is not
damaged when ISPM/DIP-IPM is replaced
! CAUTION
• Turn OFF main power before start working.
• Working and checking with the power ON may disturb correct diagnosis and may result in failure.
Procedure in case of error diagnosis
1 Remove fan motor connectors for DC fan motor from the control PCB, ISPM or DIP-IPM and turn the fan motor shaft
by hand.
Normal Fan motor shaft turns smoothly
Normal The fan motor shaft turns smoothly.
Faulty
No continuous rotary torque movement felt when turning the motor by hand. This occurs because the internal
magnet of the fan motor breaks the movement when the internal electronic circuit of the fan motor has a short-
circuit fault.
2 Measure the fan motor resistance:
Measurement procedure
Remove the fan motor connector from the control PCB, ISPM or DIP-IPM.
Connect the black test lead of the tester to the black wire pin of the fan motor connector.
Connect the red test lead to the wire connector pin to be checked.
Results
Normal Observed values will be close to the normal values in the table below.
Faulty
Obbserved values will be deviated from the normal values in the table below. (Generally, an open-circuit fault
shows∞,andashort-circuitfaultshowsseveralΩ-kΩ).Internalelectroniccircuitfaultofthefanmotorincluding
short-circuit and breakage can be checked.
Wire color for checking (Normal value)
Red-black White-black Yellow-black Blue-black
- 1MΩorgreater - 1MΩorgreater
? NOTE
Values are shown for referential purpose. While actual values may vary depending on the type of the tester, any tester can be used to
determineanyshort-circuitorbreakagebasedon∞orseveralΩor0Ωor∞.