9. TROUBLESHOOTING
NO
communications
error?
Status
Station number
setting is erroneous.
(remote station)
Initial setting is
erroneous. (master
station)
A sequence program
in the master station
is erroneous.
ON/OFF signals are
not correctly trans-
mitted.
Check and Action
Station numbers are set on the unit panel between
1 and
61 using caution not to set a same number
to more than
one station. For example, if a remote unit is set to station
1 , that station occupies station numbers
1 to 4 , and these
numbers must not be allocated to any other station.
Station numbers cannot be changed after turning on the
power for communications (24V DC).
Check the EPROM is correctly installed. Check initial data
such as the total number of remote stations, number of
remote terminals, remote station number setting, unit
type,
and FROM/TO instruction head addresses.
Check that the mode setting pin is set in
t h e m p o s i t i o n .
Check the operation mode setting switch for correct setting.
Check if the head 1/0 numbers of the master station are cor-
rect.
Check if the communications start signal is turned ON.
Designate a monitor station number with the monitor station
switch of the master station, and check that the 1/0 in-
dicator LEDs of the remote station conform with the
1/0
monitor display of the master station. (Designate the cor-
rect station number for monitoring, remote station number
+3).
If they do not conform with each other, check that the head
1/0 numbers and BFM numbers ( # l o to
# 4 1 , #110
to
#141)
of the remote station are correctly assigned, and that cor-
rect programs are executed
in the master and remote sta-
tions.