Carrier 40MBFAQ Service Manual page 25

40MBFAQ: Service Manual
DIAGNOSIS AND SOLUTION (CONT.)
PC 01 (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 wires
• IPM module board
• PCB
• Reactor
Troubleshooting
NOTE: For certain models, the outdoor PCB cannot be removed separately. In this case, the outdoor electric control box should be replaced
as a whole.
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
Check the power supply .
Is it in working order ?
YES
Check the connections and wires.
Are they in working order ?
YES
Power on and measure the
voltage between P and N .
While the unit is in the STANDBY mode,
is the voltage between P and N around
DC 310V, 340V, or 380V? When starting up
the unit, it is in the 220V~400V?
YES
Check the reactor.
Is it in working order?
YES
Replace the reactor.
NO Turn off the unit.
Ensure proper connections or
NO
replace the wires .
NO Replace the IPM board.
NO Replace outdoor PCB.
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