What were the units of measure for in the old BrewPi software?
PWM period (minutes?)
Kp (assuming this is always %)
Ti (seconds?)
Td (seconds?)
What were the units of measure for in the old BrewPi software?
PWM period (minutes?)
Kp (assuming this is always %)
Ti (seconds?)
Td (seconds?)
To clarify, what I’m trying to do is transfer all the old BrewPI PID settings over.
As far as I know, PWM is in seconds, and Kp in 1/degC, but I’m not 100% sure about Kp.
I seem to remember that the PID algorithm has changed quite a bit from BrewPi to Brewblox so you can’t necessarily move the values strait over. I had to start from scratch, at least.
I would just use a wizard en see how that works.
With BrewBlox you can see graphs of the internal PID results (P, I and D part) which makes it easier to see which part causes overshoot and needs tweaking.
Also note that our new default is to control beer temp directly and not through the fridge temp. It is simpler and seems to work well. You can still construct indirect control though.
With the defaults from the wizard, the heat side was a little less stable than before. I did end up sticking in the parameters I had previously and I didn’t get much runtime before a cold crash started but it seemed to be tracking tighter.
I’m pretty sure that before I was using your suggested setup for a 5 gallon conical with no changes and it was working perfect.
Also, I think the new charts make it easier to see variation that was always there
If you want advice on tuning, post some cycles of the PID graph
Thanks for the tip on putting the Ps, Is, and Ds on a chart. That really helped me dial things in. Now running where my worst swings are 0.2 degrees and no longer in a cycle of overheating a few 10ths and then overcooling a few 10ths.