4 posts tagged with "Relay"

After I published my last model bake-off, Gareth S. asked why I stopped after one answer. His comment inspired this eval. I gave five models up to five tries at each of 60 Ladder Logic exercises. After every failed try, the model saw the real compiler error or failed tests and could correct its answer. I wanted to see which model could reach working Ladder Logic, not only which model got the first answer right.

Relay, the AI assistant inside Rungs Studio, runs on Google's Gemini-3-Flash. It's currently free, I want to keep it free, and every message sent costs me about a cent. That sounds trivial until you multiply it by a user base that keeps growing — so I went looking for a model that was just as good at PLC code but cheaper to run.

A user was building cylinder-control logic in Studio. A cylinder is a piston that extends and retracts; a limit switch is a small sensor at the end of its travel that turns on once the cylinder gets there. His program kept raising an extending-timeout fault — after he gave the extend command, the logic waited for that "I've arrived" signal, never got it, and assumed the cylinder had jammed. The only way to clear the fault was to switch the limit switch on by hand in the simulator. He couldn't understand why he had to fake a signal like that.

Relay is the AI tutor built into Rungs Studio — the chat panel on the right side of the editor. It looks like every other AI chatbot, but every turn it sees your actual rungs and tag definitions. When you ask "is it correct?", it isn't guessing — it's reading the code you just wrote.