8.1 Initial troubleshooting
8.1.1 Checking the electrical wires and the power source
No. Item to check Check method
1 Is the power source breaker or the
fuse blown?
Check the voltage (secondary side) of the breaker and using a multimeter,
check the continuity of the fuse.
2 Is the transformer's secondary
voltage correct?
Remove the transformer's secondary connection and check the voltage
using a multimeter.
3 Is the electrical wiring properly
secured and are the connections
correctly fixed?
• Check the connection of the power wiring terminals of each terminal
board (terminals “L1” to “L1” and “N” to “N” : AC 400 V), and the
operation wiring
(communication line, terminals “1” to “1” and “2” to “2”:
DC 5 V) between the outdoor and the indoor unit coincide properly
according to the chapter 4. Otherwise, some components will be
damaged.
• Check the connection of the wiring to the PCB and ensure that the
following connections are not loose or removed:
1. Thermistor connector (each of them).
2. Remote control cable connector.
3. Transformer connector.
4. Each connector of the main power supply circuit.
• Check and ensure that shielded twisted pair cable (≥ 0.75 mm
2
) with
protection against electromagnetic interference has been used for the
communication line between units, that the total length is less than 1000
m and the wire size is within local standards.
• Check and ensure the circuit breaker and the earth leakage breaker
have been properly selected as specify in chapter 4.
• All the field wiring and the equipment must comply with local standards.
8 Troubleshooting
148
SMGB0065 rev. 1 - 12/2010
To Next Page
Loading...
