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Specifications subject to change without notice. SG-38MPRA-02
P1 (Over voltage or too low voltage protection diagnosis and solution)
Description:
Abnormal increases or decreases in voltage are detected by checking the specified voltage detection circuit.
Recommended parts to prepare:
• Power supply issues
• System leakage or blockage
• Faulty PCB
Troubleshooting
Check the power supply.
Is it in working order?
NO
Check the connections and wires.
YES
Are they in working order?
Ensure proper connections or
replace the wires.
NO
Power on and measure the
voltage between P and N.
YES
Replace the IPM board.
NO
Check the reactor.
YES
Is it in working order?
Replace outdoor PCB.
NO
Replace the reactor.
YES
Turn off the unit.
While the unit is in standby,
is the voltage between P and N around
DC 310V, 340V or 380V? On unit start up
is the unit in the 220V~400 range?