LG PQNFB17B0 - Manual (Page 89)

Troubleshooting
- Problem : The TX/RX LED of the LG-NET 1,2,3,4 of the BACnet Gateway is not blinked.
→ The TX/RX LED blinks if normal.
- Expected cause : The power is not applied to the 485 communication terminal
The RS-485 communication polarity is changed
The PI485 DIP switch is not correctly set
The power is not applied to the indoor unit
The address is not correctly set to the indoor unit
- Diagnosis
Is the power is applied
to the PI485?
Apply the power to the PI485.
NO
YES
Set the address of the indoor unit.
Is the polarity of the 485
communication connection
line correct?
Because the 485 communication has
a polarity, the connection should be
correctly done.
NO
YES
Is the DIP switch of the
PI485 correctly set?
Turn on No. 1 and 4 of the DIP switch.
NO
YES
Is the power applied to
the indoor unit?
Apply the power to the indoor unit.
NO
YES
Is the power is applied
to the PI485?
NO
Installation/Owner Manual 89
ENGLISH