Hitachi UTOPIA RAS-4HVRP2E - Page 260

10 Troubleshooting
Troubleshooting procedure
SMGB0136 rev.0 - 07/2021
258
Alarm code
57
Abnormality of fan motor protection (DC fan motor)
• This alarm is indicated when the revolution pulse output from the fan motor is lower than 20min-1 during 30
secondsanditstops.Regardingstops,whenlessthan35secondshavepassedsincefanstartup,aftertherst
abnormality is detected, if its occurs 4 times more within 5 minutes, it stops and alarm is displayed.
Does the motor run?
Yes
Check the connectors CN14 and CN15 on PCB1 and CN203,
CN204, CN201, CN202, PCN201 and PCN202 on inverter PCB.
Replace inverter PCB in the case that fan motor does not run
even if OU PCB is replaced. CN24 on PCB1 (RAS-3HVRC2)
Restart operation.
Connect it correctly
Restart
operation
Replace the fan motor and
the fuse
Replace the fan
motor
This is normal
Replace the PCB1
Replace inverter PCB
Does the fan stop by
the foreing matter?
This alarm is indicated due
to detected overcurrent by
the contrary wind. This is
normal.
No
Are the connectors
abnormal?
Faulty
Faulty
Alarm code is not indicated
Yes
Remove the foreing matter
No
Good
Check the fuses
EF1, EF2 and EF3
on PCB1, and EF1 on
inverter PCB
Good
Does the motor
run?
Yes
This is normal
No
Restart operation
Does the motor run?
No
Alarm code is
not indicated
Does thermal fuse
(R115 OR R116) on
inverter PCB blow out?
Yes
No
Yes
? NOTE
Check to ensure that DC Fan Motor is checked according to the
item “10.4.1.4 Checking procedure for other parts”.