Danfoss Plus+1 Structured Text Coding Engineer ChatGPT

[Lukey]

I created my own GPT to assist with Danfoss Plus+1 Structured Text Coding.

https://chatgpt.com/g/g-691157e9088881919df7f8883d9827f9-danfoss-plus-1-structured-text-coding-engineer

I've uploaded all the manuals and have worked out some of the nuances of ST in Guide that don't align to IEC 61131-3 language. (limitations and syntax's)

If you have any feedback or find any holes that need to be fixed please let me know so i can update the LLM.

[Rem]

Hello Lukey,
Have you run any tests?
For creating functions?
For modifying the program?
For optimization?

Thank you. 

[Matt]

Thanks for sharing! I've been doing some similar LLM experimentation by writing some skills to read/write the PLUS+1 GUIDE PLCopenXML files directly in order to avoid having to copy/paste between the LLM. In the absence of official MCP support, this is the closest I've gotten to something that truly ends up saving time because it enables refactoring in a way that the PLUS+1 IDE does not. I don't have enough confidence in it yet to share it, but thought I'd mention that it's possible and am curious if you tried going this route.

One thing I found is that LLMs seem to have a rough time understanding the cyclical nature of PLC programming, especially related to timers.

There is a similar thread over on PLC Talk that I've been following. It is an interesting read related to this topic: https://www.plctalk.net/forums/threads/does-anyone-here-use-ai-to-help-write-structured-text-codesys-beckhoff.148970/

[Lukey]

I use it heavily when dealing with math/equations and real numbers (two reasons because my math isn't great and guide doesn't handle real numbers)
I've also use it extensively for creating CAN message buffers/FIFOs.

Modify existing or optimizing code it is very useful.

It's also been able to convert existing guide screen shots or .scs files into ST code.

I update the LLM as I go when i find limitations of GUIDE.
For example, using words like DATA and OVERFLOW in ST will cause an error on compilation as those works clash with the C code complier.