We had a computer failure in our facility and lost our latest backup from a project loaded in a machine. I have an early backup, and I uploaded the program from the machine. I would like to rename all the tags from the upload, as it is a bit older PLC so it didn't retain the names. I figured I could open the db from the old program and just copy the tags and paste in the new program, or simply rename the tags in the new upload, but I am unable to. Is there a trick? Do I have to be online with the PLC to do this? Or is it just not possible. If i recall, it is an S7-300 (315-2 PN/DP).
I don't have access to the machine for some time, as I am working from home. I thought this would be a good opportunity to fix the program.