Checking Procedeure For The Dc Fan Motor; Procedure In Case Of Error Diagnosis - Hitachi RAS-(3-6)HVNC1(E) Service Manual

8 Troubleshooting
8.4.4 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
C A U T I O N
• 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
Normal
No continuous rotary torque movement felt when turning the motor by hand. This occurs because the internal
Faulty magnet of the fan motor breaks the movement when the internal electronic circuit of the fan motor has a short-
2 Measure the fan motor resistance:
Connect the black test lead of the tester to the black wire pin of the fan motor connector.
Normal
Obbserved values will be deviated from the normal values in the table below. (Generally, an open-circuit fault
Faulty shows ∞, and a short-circuit fault shows several Ω - kΩ).Internal electronic circuit fault of the fan motor including
Model
RAS-(2-2.5)HVNP1
RAS-3HVN1C
RAS-(3-6)H(V)NP1E (both)
RAS-(4-6)H(V)NC1E
RAS-(8-10)HN(P/C)E (both)
RAS-12HN(P/C)
N O T E
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 ∞.
310
SMGB0087 rev.0 - 12/2013
Models with DC motor(s)
RAS-(2-2.5)HVNP1
RAS-3HVNC1
RAS-3HVNP1E
RAS-(4-6)H(V)NC1E
RAS-12HN(P/C)
RAS-(4-6)H(V)NP1E
RAS-(8-10)HN(P/C)E
Fan motor shaft turns smoothly
The fan motor shaft turns smoothly.
Measurement procedure
Remove the fan motor connector from the control PCB, ISPM or DIP-IPM.
Connect the red test lead to the wire connector pin to be checked.
Observed values will be close to the normal values in the table below.
short-circuit and breakage can be checked.
Motor model
FPD10U40S-902
SIC-61FW-D858
EQDW04AHT
SIC-81FW-8183
Number of motors
1 Piece
1 Piece (upper)
2 Pieces
circuit fault.
Results
Wire color for checking (Normal value)
Red-black White-black
1MΩ or greater
1MΩ or greater
∞
1MΩ or greater
Yellow-black Blue-black
1MΩ or greater
1MΩ or greater
∞
1MΩ or greater