PID Troubles

[Mudpie]

I have a Backwoods Smoker G2 in which I recently built a PID controller common on other forums connected to a 1800 watt smoker heating element. I can never get it to reach the higher temps (260-275F) without crashing back into the low 200s. Ive tried AutoTune but it take hours to get over 240. Any ideas.

 

[tallbm]

I have a Backwoods Smoker G2 in which I recently built a PID controller common on other forums connected to a 1800 watt smoker heating element. I can never get it to reach the higher temps (260-275F) without crashing back into the low 200s. Ive tried AutoTune but it take hours to get over 240. Any ideas.

Hi there and welcome!
Does your smoker have have a high temp safety cutoff switch by any chance?
That could be killing power to your heating element if the switch is failing or simply has a lower threshold like 250F or so.

I know MES units have them and they are a very common failure point in the MES units.

 

[zwiller]

^What he said. I would do a test. Monitor temp somehow and run sans PID/straight to power a short time to confirm. Be careful and pay attention the whole time as you could damage smoker/start fire/worse.

 

[Mudpie]

Update. I reset the PID to P=1 I=0 D=0 and it will hit my target temp and hold it.

 

[dsk]

You have set your PID to be a simple thermostat, which is working well for you. If you are satisfied, no need to go further. I have found that some PID controllers I have bought (cheaply off Aliexpress) do not correctly implement a PID algorithm. You mention you built your controller, and this may be the root cause of your performance issue in PID mode.

 

[river100]

You have set your PID to be a simple thermostat, which is working well for you. If you are satisfied, no need to go further. I have found that some PID controllers I have bought (cheaply off Aliexpress) do not correctly implement a PID algorithm. You mention you built your controller, and this may be the root cause of your performance issue in PID

Update. I reset the PID to P=1 I=0 D=0 and it will hit my target temp and hold it.

Are you getting any overshoot with those settings?

 

[river100]

You have set your PID to be a simple thermostat, which is working well for you. If you are satisfied, no need to go further. I have found that some PID controllers I have bought (cheaply off Aliexpress) do not correctly implement a PID algorithm. You mention you built your controller, and this may be the root cause of your performance issue in PID mo

 

[dr k]

Are you getting any overshoot with those settings?

I use this setting on my Auber WS-1510ELPM. If P=0 no matter the other I and D settings, then it's an on off controller at set temp. In the setting above the controller is full power closed circuit 1 degree below set temp then 1/2 degree below set temp switches for 50% power and off at set temp. For 265 smoking in the Mes 40 volume with mailbox mod and open top vent there's no over shoot and gets up to temp in an hour or less with a 17lb brisket, butts or ribs. It may over shoot preheating empty a few degrees but at this higher temp and how it breathes with the volume it's the quick output at 50% 1/2 degree below set temp after getting to set temp that keeps the cook at 265 or 1-2 degrees below. Best setting for my set up without waiting to get to set temp full PID. Auber uses this P mode in their directions with P=7 so 7 ° below set temp is full power 7/7, 6 degrees below set temp is 6/7 power until off at set temp but on the way down the response at 1 degree below set temp 1/7 is not enough power to hold and the temp drops so set to P=1 is 1/2, 50% power the perfect output before full power to hold within a couple degrees even though the resolution is in 1 degree increments the response is 1/2 degree when P=1.