Carrier 40MBDAQ - Page 33

40MBDAQ: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
33
DIAGNOSIS AND SOLUTION (CONT.)
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 wires
• IPM module board
• Outdoor PCB
• Bridge rectifier
• PFC circuit or reactor
Troubleshooting
Voltage protection
Check whether the power
voltage is normal.
Measure whether the outdoor
terminal voltage is normal.
Restart the unit when the power supply
reaches normal level.
No
Yes
No
Reconnect the
wires well.
Yes
Yes
No
Replace the IPM board.
If the IPM board and the main board are in
the board, replace the outdoor main PCB.
Yes
Replace the PFC module (if present).
No
Yes
Measure whether the voltage
between L and N is normal.
Yes
Measure whether the input voltage
of the bridge rectier is normal.
Yes
No
No
Measure whether the voltage
between P and N is normal.
Replace the bridge recier.
No
Is the
bridge rectier
functioning normally?
Check the wiring of
the reactor or indictance.
Reconnect the wiring.
No
Check whether the
reactor or indictance
is normal.
Yes
Replace reactor
or inductance.
No
Is the wiring of power wires
well connected?
Reconnect it.
Is the wiring between
L and N well connected?
Reconnect it.
Is the bridge rectier wiring
well connected?