PLC Version Control

Question

I need to come up with a CM process for PLC code.

Currently, the system is developed using RSLogix 5000. The build product is a monolithic file that can be loaded onto a PLC for execution and edited directly in the development environment. With multiple developers, this has become a problem. They're stepping on each others changes.

As an analogy, it's as if, when doing Java development, the only wway to edit and save the source would be to load up a *.jar file into your IDE, make the change, and then save it back to the jar file. This is less than ideal.

How can I coordinate changes between multiple developers working with PLC's?

Answer 1

I use Unity Pro, so this may not apply for other brands.

Unity can export an "archive" file which is XML which describes the PLC program and IO setup in its entirety. After commissioning changes, I create an export and check it in to my local Git repo. This gets me an annotated history of changes, but no visual comparison. I can always use UnityDiff for comparison.

Check out http://www.mdtsoft.com/ also

Answer 2

You need specialized versioning system for PLCs like VersionDog.

From the manufacturer:

"Special support with Smart Compares for SIMATIC S5, SIMATIC S7, SIMATIC PCS 7, WinCC, WinCC flexible, InTouch, CoDeSys, TwinCAT, Phoenix PC WORX, RSLogix, Schneider Modsoft, Schneider Concept, Schneider Unity, SINUMERIK 840D, Bosch IndraWorks and more. Also robot programs from ABB and Kuka and office related data formats like Microsoft Word, Microsoft Excel and Adobe PDF are perfectly supported by versiondog.

Update: Here is a screenshot showing ladder version compare. I guess that's what most PLC folks are interested in. We also use it to schedule e-mail report if PLC offline and online application versions are a match, as an alarm that something has been changed in PLC but not put into version control server.