Error Messages and Alarm Outputs
Section 5-1
Fatal Errors
Item
Cause
CPU indicators
Peripheral
Device error
Power RUN ERROR WDT ALARM OUT INT COMM
message
Power interrup- Power interruption
Unlit
Unlit Unlit
Unlit Unlit
Unlit
Unlit
POWER FAIL
tion
occurred and
lasted longer than
the specified limit.
Expansion CPU Expansion CPU
Lit
Unlit Unlit
Unlit Unlit
Unlit
Unlit
POWER FAIL
Rack power
OFF
Rack
Power Supply Unit
is OFF.
CPU error
Watchdog timer
Lit
Unlit ---
Unlit Lit
Lit
---
---
---
---
---
---
---
WDT ERR
Memory error
Error occurred dur- Lit
ing internal
MEMORY ERR
memory and Ex-
pansion DM verifi-
cation.
I/O bus error
Erroneous data
transferred be-
tween CPU and I/O
Units
Lit
Unlit Lit
Unlit Lit
---
---
---
---
---
---
---
---
I/O BUS ERR
Duplicated
number
Rack numbers and Lit
CPU Bus Unit unit
numbers or I/O
NO DUPL ERR
words are assigned
in duplicate.
CPU bus error
I/O points over
Error in data trans- Lit
fer between CPU
and CPU Bus Unit
or watchdog timer
error in CPU Bus
Unit.
Unlit Lit
---
---
---
---
---
---
---
---
CPU BUS ERR
Too many I/O
Lit
Unlit Lit
I/O OVER
points or too many
Units are registered
in the I/O table.
I/O setting error Input/Output desig- Lit
nation is wrong for
Unlit Lit
Unlit Lit
---
---
---
---
---
---
---
---
I/O SET ERR
I/O Unit.
Program error
END(001) is miss-
ing, or the capacity
of the user memory
is exceeded.
Lit
NO END
INSTR
PROGRAM
OVER
Cycle time over Cycle time monitor Lit
time is exceeded.
Unlit Lit
---
---
---
---
SCAN TIME
OVER
Fatal SFC error SFC syntax error.
Lit
Lit
Unlit Lit
Unlit Lit
---
---
---
---
---
---
---
---
SFC ERR
System failure
(FALS)
FALS was ex-
ecuted in program.
SYSTEM FAL
77
OMRON [ OMRON ELECTRONICS LLC ]
