Troubleshooting; Error Messages - Omron ZEN Operation Manual

Troubleshooting

6-1 Troubleshooting
ERR
6-2

Error Messages

Power ON but No Operation
Error message
MEMORY ERR
I/O BUS ERR
UNIT OVER
I/O VRFY ERR
Note
116
Search for the cause of the error and take immediate
countermeasures if ERR or any other error message appears on the
LCD screen (for CPU Units with display) or the ERROR indicator is lit
(on LED-type CPU Units).
CPU Unit with display
The following tables list the error messages that are displayed when
an error occurs.
Probable cause
Program error.
Expansion I/O Unit
connection error.
More than 3 Expansion I/O
Units connected.
Bit type that cannot be
used with system
configuration included in
ladder program. (See note.)
I/O Verification Error
Expansion I/O Unit I/O bits (X/Y): Bit not allocated in system
configuration has been used.
Analog comparators (A): Used with AC power supply type.
Weekly timers (@)/Calendar timers (∗): Used with ZEN with LED
displays.
ERROR
LED-type CPU Unit
without LCD
Possible solution
The ladder program and parameter settings
have been cleared. Write a program to the
ZEN again.
Turn OFF the power supply and check that
the Expansion I/O Units are connected
properly.
Turn OFF the power supply and reduce the
number of Expansion I/O Units to 3 or less.
Remove the illegal bit type from the program.
Section 6-1