ABB AC500-S Safety User Manual page 27

ID Behavior
18. If a breakpoint is reached in
CODESYS Safety during debug-
ging and you try to force a vari-
able, then this variable is updated
with the forced value only in the
next safety CPU cycle.
19. During project download to the
safety CPU, the download window
stays with 0 bytes of downloaded
code forever or an error message
pops up.
20. Unable to log in to the safety CPU
from CODESYS Safety after
logout.
21. Diagnosis message with error
severity level 3 and error text
"Measurement underflow at the
I/O module" appears in non-safety
CPU diagnosis system despite
the fact that overcurrent and not
undercurrent was observed for
the given AI581-S input channel.
22. "Enable debug" parameter =
"ON" was set for the safety CPU
and correctly loaded to non-safety
CPU. However, one still cannot
debug on the safety CPU.
23. After using CODESYS Safety
menu item "Online è Reset", the
safety CPU goes to DEBUG
STOP state (non-safety mode).
Safety I/O modules go to module
passivation state. If you log in to
the safety CPU, then you can see
OA_Req_S = TRUE bits in
PROFIsafe instances of F-
Devices. The safety application is
not executed by the safety CPU,
but you still can set OA_C =
TRUE for F-Devices and they will
go to RUN mode. The safety CPU
remains in DEBUG STOP state
(non-safety) all the time.
24. Error message "Error in configura-
tion data, safety PLC cannot read
configuration data" is available on
the safety CPU.
2020/06/19
Potential cause
The safety CPU is single-
threaded.
"Enable debug" parameter was
set to "OFF" for the safety CPU
and this configuration data was
downloaded to non-safety CPU.
Too fast log in to the safety CPU
after logout in CODESYS Safety.
The internal detection mechanism
is not always able to differentiate
between over- and undercurrent
because the overcurrent is often
followed by undercurrent effects in
AI581-S electronics.
CODESYS Safety projects on
your PC and in the safety CPU
are not the same. You may get
also the following message
window with the text: "The pro-
gram has changed! Download the
new program?".
PROFIsafe F-Host does not run in
fail-safe mode after using
CODESYS Safety menu item
"Online è Reset".
● Downloaded configurations on
non-safety CPU and safety
CPU do not fit to each other.
● No boot project is loaded on
the safety CPU.
3ADR025091M0208, 12, en_US
Overview of AC500-S safety PLC
Troubleshooting
Remedy
This behavior is as designed.
Set "Enable debug" parameter to
"ON" , generate a new configura-
tion and download project to non-
safety CPU. New project code
can be now downloaded to the
safety CPU through CODESYS
Safety.
Wait a few seconds (~ 5 - 10 s)
after logout from the safety CPU
before you perform log in to the
safety CPU in CODESYS Safety.
There is no remedy for this
problem yet.
Download your CODESYS Safety
project from your PC to the safety
CPU and debugging shall be pos-
sible now.
This behavior is as designed in
Ä Chapter 3.1.5.1
the safety CPU
"Description of safety CPU
module states" on page 43.
● Download valid configura-
tions, as part of boot projects,
on non-safety CPU and the
safety CPU, respectively, and
make sure that they fit to each
other.
● Download a valid boot project
on the safety CPU.
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