Hysterisis problem

[artguy]

I have a simple process with no exit condition I am using to run my chest freezer as a cool fermenter chamber. I have hysteresis selected. THe temp probes are all reading fine, I have the correct system settings for it, it is set to cool, it has a pid sample rate of 3, output period of 3, min pulse and max pule of 100%. I have the set point at 46 degrees but it won't turn on the output until it reads 50 degrees. What do I have set wrong to make it wait until it is a whole 4 degrees warmer than it should be before it turns on the relay?

[JonW]

Under "System Settings", "PID and Hysteresis Output Control Settings" - What is your Hysteresis degrees setting? That field dictates the degrees swing you will get above/below your set point.

Also, the PID Sample Period, Output Period, Min Pulse & Max Pulse are only used for PID, not hysteresis.

[artguy]

Got it! Thanks. I feel silly for overlooking that. It was set to 4 so I set it to 1.5


Thanks!