Daikin Emura RXJ20A5V1B Service Manual page 140

4 | Components
Service manual
140
5 Confirm via the service monitoring tool that the DC fan motor assembly
receives an ON signal.
6 Turn OFF the unit via the user interface.
7 Turn OFF the respective circuit breaker.
DANGER: RISK OF ELECTROCUTION
Wait for at least 10 minutes after the circuit breaker has been turned OFF, to be sure
the rectifier voltage is below 10 V DC before proceeding.
8 Disconnect the DC fan motor connector S70 and measure the resistance on
the connector pins shown below. The measured resistance MUST be:
VDC
1
2
3
7
INFORMATION
The measured resistance values may deviate from the listed values due to instability
during the measurements.
DC fan motor resistance measurements
are correct?
Yes
No
9 Turn ON the power of the unit.
10 With the DC fan motor connector S70 disconnected from the main PCB,
measure the voltage on the connector pins 4-7 (= fan motor power supply) on
the main PCB.
Result: The voltage MUST be 200~390 V DC.
11 Measure the voltage on the connector pins 4-3 (= fan motor control) on the
main PCB.
Result: The voltage MUST be 15±10% V DC.
Are both measured voltages correct?
Yes
No
12 Measure the voltage on the DC fan motor connector S70 pins 2-4 (= rotation
command) on the PCB.
Result: The measured voltage should be 0~7 V DC. It should NOT be 0 V DC.
Is the measured voltage 0 V DC?
Yes
No
Comm
4
4
4
4
Action
Continue with the next step.
Replace the DC fan motor, see
procedures" [
Action
Continue with the next step.
Perform a check of the main PCB, see
"Checking
Action
Perform a check of the main PCB, see
"Checking
Continue with the next step.
Resistance
>1 MΩ
>100 kΩ
>100 Ω
>100 kΩ
"Repair
4
141].
4
procedures" [ 117].
4
procedures" [ 117].
RXJ20~50A + FTXJ-A(W)(S)(B)
Split Emura 3 R32
ESIE22-04B – 2022.08