Samsung AC071JN4CEH Service Manual page 72

Troubleshooting
1. Test Item
1) Check the connection of fan connectors (CN90, CN91). [In case of RC072DHXB , CN901]
2) Check the voltage of the fan motor connector in the inverter PBA of the outdoor unit.
3) Check the power supply of the inverter PBA of the outdoor unit.
4) Check the single fan motor. (Do not forget to separate the motor connector 30 seconds after power off!)
2. Check procedure
Check after power OFF!
Check the connection
of the fan connectors (CN90, CN91 or CN901).
1. Is the outdoor fan connector correctly connected?
2. Are the wires of the external fan
connector correctly connected?
Check the voltage
of the fan connector to
the inverter PBA of the outdoor unit.
After power is ON,
check the voltage between connector pins.
1. Is the DC_Link voltage correct?
(Normal: 280Vdc ≤ DC_Link voltage ≤ 360Vdc)
2. Is the fan control voltage correct?
(Normal: 14Vdc ≤ FAN control voltage ≤ 16Vdc)
3. Is the fan command voltage?
(Normal: 2Vdc ≤
FAN command voltage
≤ 5Vdc)
Check the single fan motor.
(30 seconds after power is off,
1. Are the resistance values between pins of
the fan motor connector similar to those
in the following table?
After power is on, check everything is normal.
End the service.
At least 30 seconds after power is OFF, attach/detach the fan motor connector!
Check the single inverter PBA or fan motor and only if there is a fault, replace!
Do not replace the main PBA of the outdoor unit relating to the fault in the fan motor!
If the error is indicated on 7-segment of the main PBA of the outdoor unit, the main PBA of the outdoor unit has no fault.
In case of a control problem, it is possible to solve with S/W update.
4-32
Yes
Yes
Yes
Connect the fan corrector (CN90, CN91 or CN901)
No
correctly. Power is on.
state is normal, end the service.
Connect the connections of Connect the connections of
the outdoor unit which has the outdoor unit which has
two outdoor fans. one outdoor fan.
[RC090/100/125/140/145
AC FCA ]
Check the power supply of the inverter PBA of the outdoor unit.
No
1. Check by referring to When the outdoor unit power is not ON –
Initial Diagnosis.
the PBA at the fault in the inverter PBA.
#1-#3 DC_Link Voltage (between DC_link and GND)
#4-#3 DC_Link voltage (between DC15V and GND)
#5-#3 FAN command voltage (between fan control and GND)
Measuring Part
No
Motor Connector
Threatened to cause secondary damage to the motor and the PBA.
After confirming the
[RC072DHXB ]
Check everything is normal after replacing
End the service.
280Vdc ~ 360Vdc
14Vdc ~ 16Vdc
2Vdc ~ 5Vdc
Diagnosing Part Value of good product
#5(YEL)-#3(BLK) resistance
Open (infinite resistance)
(between fan control and GND)
#4(WHT)-#3(BLK) resistance
Approx. 1.0kΩ ~ 3kΩ
(between DC15V and GND)
#5(YEL)-#3(BLK) resistance
Approx. 230kΩ ~ 280kΩ
(between fan control and GND)
#6(BLU)-#3(BLK) resistance some MΩ or more or open
(between feedback and GND) (infinite resistance value)
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