LG RCWW Operation & Maintenance Manual page 114

8. TROUBLESHOOTING
114
Com connectors(23/24)
Figure 70 Master or Slave board current measuring circuit
Communication error
It is the error caused by no communication corresponding to the displayed messages between each board. First,
check the communication line connection status between each board. At this time, 2 RDX+ and RDX- lines of master
board should be connected to the same polarity of RDX+ and RDX- of slave board and as well as of relay board. If
they are not properly connected to the corresponding communication connector, communication cannot be made. So
they should be connected to the designated connectors.
Corresponding input connector
Master or slave board
Com connectors(23/24)
Master or Slave board
Figure 71 Master or slave board current measuring circuit
D/I input
- Place at DC 30V.
- If D/I input is open, measured voltage
should be within 18V±5%.
- If D/I input is closed, measured voltage
(-) (+)
should be 0V.
- lace at DC 30V.
- The measured voltage should be within 18V±5%.
- Com connectors(23/24)
Corresponding input connector