Daikin SUPER MULTI NX G Series, Руководство по обслуживанию

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SiUS12-928_A Troubleshooting
Service Diagnosis 146
5.26 Low-voltage Detection or Over-voltage Detection
Remote
Controller
Display
U2
Outdoor Unit LED
Display A 1 2 3 4
Method of
Malfunction
Detection Low-voltage detection:
An abnormal voltage drop is detected by the DC voltage detection circuit.
Over-voltage detection:
An abnormal voltage rise is detected by the over-voltage detection circuit.
Malfunction
Decision
Conditions
Low-voltage detection:

The voltage detected by the DC voltage detection circuit is below 150 V for 0.1 second.

If the error repeats 16 times, the system is shut down.

Reset condition: Continuous run for about 60 minutes without any other error
Over-voltage detection:

An over-voltage signal is fed from the over-voltage detection circuit to the microcomputer.

The compressor stops if the error occurs, and restarts automatically after 3-minute standby.
Supposed
Causes

Supply voltage is not as specified.

Defective DC voltage detection circuit

Defective over-voltage detection circuit

Defective PAM control part
Troubleshooting
Correct the power supply.
Replace the outdoor unit
PCB.
Check for such factors for a
long term.
∗
Try to restart a few times.
(R7150)
Caution
NO
YES
YES
NO
YES
(Precaution before turning on the power again)
NO
Replace the fan motor or
the outdoor unit PCB.
Check the supply voltage.
Rotate the fan by hand.
Disturbance factors
∗
Noise
∗
Power supply distortion
Repeat a few
times.
Make sure the power has been off for
at least 30 seconds.
Be sure to turn off the power switch before connecting or disconnecting
connectors, or parts may be damaged.
Turn on the
power again. System
restarted?
Does the fan rotate
smoothly?
Supply voltage as
specified?