Table of Contents
Advertisement
S5-95F
14.2.2 Descriptions of the ISTACK Flags
Table 14-6 shows the causes of error which can cause interruption of a program scan. The PLC
goes to "STOP" in all cases.
ISTACK
Flags
ASPFA and
Program transfer error
KEINAS
Overflow of the internal program memory
NNN
during compilation.
SAC=FFFF
PG PLC or memory submodule PLC
BAU
During automatic program loading
•
No battery/no charge and no valid
program on memory submodule
NAU
Power failure
NINEU
Program in PLC memory is defect.
Cause:
•
Power failure occurred during:
- Memory compression
- A block transfer from PG to PLC
- An overall PLC reset
•
Battery was changed during a power
outage
NNN
•
Non-decodable instruction
•
Nesting level exceeded
•
Parameter assignment error
PEU
•
Expansion module not connected
•
I/O bus fault
•
Maximum length of shift register
exceeded
•
Unknown module
•
Module in wrong slot
STOPS
Mode switch set to STOP
STS
• Software STOP programmed by user
(STP)
• STOP request issued via programmer
STUEB
Block stack overflow. Maximum block
nesting depth error (16) exceeded.
EWA 4NEB 812 6210-02
Testing the User Program and Storing It on the Memory Submodule
Table 14-6. Interrupt Analysis
Cause of Error
or from the memory submodule to
the PLC
Corrective Measures
Shorten program, compress memory
Replace battery and rewrite or reload
program
Execute overall reset and reload
program
Eliminate program error
•
Check power supply in expansion
unit
•
Check all connections
•
Check module slots
•
Replace defective modules/bus
modules
Set PLC to RUN
Eliminate program error
14-9
Advertisement
Table of Contents
