LG RCWW Operation & Maintenance Manual page 113

Connect tester to the digital input channel where
problem occurred as shown in Figure 1, and find out
whether the input is normal.
Is input normal?
Check the condition of
controller power connector's
connection.
Is the connector properly
connected?
Measure the voltage of the
controller. (Refer to Figure 2.)
Is I/O board voltage
normal?
Check the condition of communi-
cation cable connection between
master board and slave board.
Digital input problem
N
Y
N
Y
N
Y
Figure 69 Digital input problem
Check whether the pertain wires and input
sensor are operating normally.
Are they normally
connected?
Y
Replace I/O board.
Is the main power of
controller normal?
N
Replace main board.
8. TROUBLESHOOTING
113
N
Re-connect
the cable
firmly.
Y