Power Supply Insufficient Or Instantaneous Abnormality - Daikin REYQ-XA Service Manual

SiUS371901E

3.63 Power Supply Insufficient or Instantaneous Abnormality

U2
Error Code
Applicable
All outdoor unit models
Models
Method of Error
Detect the voltage of capacitor of the main circuit in the inverter PCB.
Detection
Error Decision When the voltage in the DC circuit (between diode module and power module) falls below 190 VDC
Conditions (for 208/230 V models), 380 VDC (for 460 V models) or 560 VDC (for 575 V models).
Supposed
Causes
Troubleshooting
Service Diagnosis
Abnormal power supply voltage
Instantaneous power failure
Open phase
Defective inverter PCB
Defective outdoor unit main PCB
Defective compressor
Defective main circuit wiring
Defective fan motor
Defective connection of signal cable
Be sure to turn off the power switch before connecting or disconnecting
Caution connectors, or parts may be damaged.
Check for power supply
conditions.
(1) Power supply voltage falls
within ±10% of the rated
voltage?
(2) Any open phase in the
power supply wiring or any
wrong wiring?
(3) Imbalance in the power
supply voltage is
maintained within 12 V?
There are
some defects in the
power supply conditions
aforementioned.
NO
The insulation
resistance of the
compressor is not more
than 100 kΩ.
NO
A
Go to the next page.
YES
YES
Troubleshooting by Error Code
Fix the defects.
Replace the compressor
(M1C).
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