Looks like the same problem but my german is a bit rusty.
http://www.sps-forum.de/simatic/40935-fehler-bei-sfc83-read_dbl.html
Looks like it has something to do with the DB changing while the SFC is in progress...I think....
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Yea, i read something like that also.
But this shouldnt be in my case. I have nothing that changes the values in my Source DB except the VAT table im using to put in values.
I have simply done like this
Created two DBs, 1 linked and 1 unlinked.
In them i have created an array with 2 INTs. So they both look the same.
Then i put in my values via a VAT table in the LinkedDB.
I activate a bit which triggers the REQ on the Write SFC to write from the LinkedDB array [0] to the Unlinked array [0].
I then deactivate that bit, change the value in the LinkedDB to 0.
Activate the bit which triggers the REQ on the Read SFC to read from the Unlinked array [0] to the Linked array [0].
So this works on my test rig but not on the actual PLC where i need it.
Edit: I saw now when i read the post one more time that it worked for him for a while if he made the PLC go from RUN to STOP and back. I have not been able to try this due to production.
Mabye i have done something so my PLC go stuck in the same mode as for this guy.
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