benjammn said:
The PID will calibrate to your particular unit if you bring temps up to the desired level and choose the AutoTune function.
I agree with you Ben, but I believe you don't want to bring it up to temp prior to hitting the AutoTune. My understanding is you want to start AutoTune when smoker is cold, so it can learn not to overshot the temp you desire on the initial rise.
I just started this method this morning with 2 ribs in place, smoker temp ~49F to start, outdoor temp ~1F, 225F target temp and sensor 1 on topmost rack with the ribs. Observations so far:
-AutoTune initial overshot was 243F (I'm sure it will make some adjustments to P value)
-At about ~200 (really rough here as I was snapping a picture) I hear a small Woof, exhale of smoke almost like a small dud explosion you would see on myth busters. Then smoke again. Not sure what this was about, maybe the wood starting to burn instead of smoke? Anyway if that is the case hope that doesn't cause the tuning to "overthink" the overshot temp.
-Lastly I just had to snap a picture while it was at ~240F to show you guys Minnesota style thermo-imaging.
I'll update with my post AutoTuned settings, but would be curious as to the results of others with different variables / factors to see how close they are to mine and how far they are away from initial / default settings.
Edit - Results:
Setting Original My AutoTuned #3
P 70 75
I 600 715
d 150 89
Had to open after 3 hrs of cooking ribs to throw in a Meatloaf for the kids. Temp dropped to 150F then after I closed the door it did the following (150F > 225F > 222F> 225F) one iteration before settling back into bouncing between 1F of 225F. Since this is my first time using PID on smoker not sure how this compares to default settings. At a certain point here I think I'm splitting hairs. Time for a beer, yes it is before noon... Don't judge... ;D
Cheers,
Wik