Comparing PLC Programs

Can you save the files as text? If so, you could compare in a word processor, or use a text file compare utility.

tried that unfortunately it is all in ladder and the text export dosent seem to work with ladder

Download one backup.

Try to go online with the other backup.

List the not equal logic.

That's how I'd do it with Proficy. Hope that gives you some ideas.

From what I recall of Modicon it will report differences but not list them, mores the pity. It would have saved me hours.

ended up doing it manually wouldn't have been too bad If I was at the plc but I'm in the office and the plc is in a different country.thanks anyway

Well done - was prob'ly the easiest way in the end.

_{Don't you just love it when people don't read through the thread, and start posting "answers" when you've already solved the problem?}

Beyond Compare is an excellent file comparison tool

www.scootersoftware.com/

You might look at it

You have all but one choice. Print out the two programs and review page to page. I do not know of any software out there that will allow you to compare two Ladder programs to one another rung by rung.

Quickest way I found was to simply compare the file sizes. If the sizes were different I would load them on to two PC's and compare them side-by-side, better than printing them. I would also start from the end of the program and work back. The end being the place most alterations are liable to be made and glaringly obvious if new networks have been added.

One major problem I had was a guy from the design and development department showing up and doing changes on line, while I would take a copy of the program and alter it in the office. He was doing stuff for data logging while I was doing production sequence alterations. So the outcome would be I'd take my altered copy of the program back to the plant and download it, overwriting 2 days of his work. He's not happy a happy bunny and being higher up the pecking order thought he he'd try and shoot me down. The plant engineer found himself as referee in the argument, poor sod hadn't a clue what we were arguing about. The guy from the D&D dept. was not impressed to be told to work around me and my methods.