This question could arguably be described as in the retrocomputing realm of IoT. Although the protocol in question is 30 years old, the use case seems to align with industrial IoT applications.
So for this specific question, its a little unclear what the question is about, but it seems the general subject is on-topic. It seems unlikely that the experts in this area will be any more active in a more conventional networking forum. If anything, I'd suggest Electronic Engineering is likely to be the closest match.
One option is to identify a technological step or date which allows a choice of if a specific question is IoT, or simply a question about working with a legacy implementation.