Mitsubishi Electric PURY-100TMU, Service Handbook

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Checking code Meaning, detecting method Cause Checking method & Countermeasure
4103
4115
Reverse phase
abnormality
Power supply
sync signal
abnormality
Reverse phase (or open phase) in
the power system is being de-
tected, so operation cannot be
started.
The frequency cannot be deter-
mined when the power is switched
on.
(The power supply’s frequency
cannot be detected. The outdoor
fan cannot be controlled by phase
control.)
1) The phases of the power supply (L1,
L2, L3) have been reversed.
2) Open phase has occurred in the
power supply (L1, L2, L3).
3) The wiring is faulty.
4) The fuse is faulty.
5) The circuit board is faulty.
1) There is an open phase in the power
supply (L1, L2, L3).
2) The power supply voltage is dis-
torted.
3) A fuse is defective.
4) The circuit board is defective.
If there is reverse phase before the
breaker, after the breaker or at the
power supply terminal blocks TB1, re-
connect the wiring.
Check before the breaker, after the
breaker or at the power supply termi-
nal blocks TB1, and if there is an open
phase, correct the connections.
a) Check if a wire is disconnected.
b) Check the voltage between each
of the wires.
Check 1 the connections, 2, the con-
tact at the connector, 3, the tightening
torque at screw tightening locations and
4 for wiring disconnections.
TB1~CN20
Refer to the circuit number and the wir-
ing diagram plate.
If F01 or F02 on the MAIN board is
melted, (Resistance between both
ends of the fuse is
∞
), replace the fuses.
If none of the items in 1) to 4) is appli-
cable, and if the trouble reappears even
after the power is switched on again,
replace the MAIN board (when replac-
ing the circuit board, be sure to con-
nect all the connectors, etc. securely).
Check before the breaker, after the
breaker or at the power supply termi-
nal blocks TB1, and if there is an open
phase, correct the connections.
If the power supply voltage waveform
is distorted from a sine wave, improve
the power supply environment.
If F01 or F02 on the MAIN board is
melted, (Resistance between both
ends of the fuse is
∞
), replace the fuses.
If none of the items in 1) to 3) is appli-
cable, and if the trouble reappears even
after the power is switched on again,
replace the MAIN board (when replac-
ing the circuit board, be sure to con-
nect all the connectors, ground wires,
etc. securely).