ABB AC500-S Safety User Manual page 30

Overview of AC500-S Safety PLC
Troubleshooting
ID Behaviour
17. After power-on of SM560-S
Safety CPU, it may happen that
SM560-S Safety CPU does not
go to RUN mode. DIAG LED is
ON and no boot project is
loaded to SM560-S Safety
CPU. If you attempt to login to
SM560-S Safety CPU, then the
following error message can be
seen in CoDeSys Safety: "No
program on the controller!
Download the new program?".
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 SM560-S
Safety CPU cycle.
19. During project download to
SM560-S Safety CPU, the
download window stays with 0
bytes of downloaded code for-
ever or an error message pops
up.
20. Unable to login to SM560-S
Safety CPU from CoDeSys
Safety after logout.
21. E3 diagnostic message with
error text "Measurement under-
flow at the I/O module" appears
in PM5xx diagnosis system
despite the fact that overcurrent
and not undercurrent was
observed for the given AI581-S
input channel.
30
Potential Cause
SM560-S power dip function is
triggered if the pause between
the power-off and the following
power-on phase is less than
1.5 s. The boot project is still on
SM560-S Safety CPU, but not
loaded due to power dip detec-
tion. Thus, there is no need to
reload any boot project to
SM560-S Safety CPU.
SM560-S Safety CPU is single-
threaded.
"Enable debug" parameter was
set to "OFF" for SM560-S
Safety CPU and this configura-
tion data was downloaded to
PM5xx.
Too fast login to SM560-S after
logout from SM560-S in CoD-
eSys Safety.
The internal detection mecha-
nism is not always able to dif-
ferentiate between over- and
undercurrent because the over-
current is often followed by
undercurrent effects in AI581-S
electronics.
AC500-S
Remedy
Do power-off and power-on of
SM560-S Safety CPU with a
pause between power-off and
power-on phase ³ 1.5 s.
This behavior is as designed.
Set "Enable debug" parameter
to "ON" , generate a new con-
figuration and download CoD-
eSys project to PM5xx. New
project code can be now down-
loaded to SM560-S Safety CPU
through CoDeSys Safety.
Wait a few seconds (~ 5 – 10 s)
after logout from SM560-S
before you perform login to
SM560-S in CoDeSys Safety.
There is no remedy for this
problem yet.
30.03.2017