Fine tuning PID

Mr Walleye · February 24, 2007, 05:46:08 AM

I decided to start a new post so I wasn't taking over SmokinStu's thread. Anyway this is my previous post.

"Here's my current PID numbers:

P=400
I=225
D=225

I have ran the AT 3 times now. Each time the settings are a little different but the outcome is almost the same. I am currently doing 2 butts at 210 degrees with a temp swing of 2 degrees each way. Does anybody have any thoughts on which setting I should try tweaking and in what direction? I would be interested in hearing what anybody else's settings are."

Interestingly enough, it is now just about 8 am so the butts have been in about 12 hours. They are now at 160 degrees. The interesting part is every time I've checked it this morning the temp has been dead on 210 degrees. Does the Auber PID "learn", so to speak, as time goes on? Or, is it more a factor of the contents of the tower just coming to a more stable temp?

I would still like to here what other peoples P,I & D numbers are and what other mods they have done that might influence it such as circulation fans.

Mike

Mr Walleye · February 24, 2007, 06:08:14 AM

PS:

Each time I ran the AutoTune I set the target temp at 200 degrees. My last 2 smokes were jerky at 165 degrees. Thinking about this, the reason I had a slightly larger temp fluctuation may have been because of this?

Again right now my target temp is 210 degrees which is very close to the AutoTune temp of 200 degrees.

Mike

smokin stu · February 25, 2007, 08:20:31 AM

Just plugged in my PID and tried it out. No sparks, no fires. Now it is a couple of degrees below freezing outside and the winds blowin with a storm coming in, so my empty smoker had a hard time getting up to 200 degrees. I wish the BS came with a more powerful heater.... may be my next upgrade.

P=10, I=257. D=3 for my autotune. Not really sure what that means.

I will wait for a warmer day and prep some food for the BS and really try out the PID.

Mr Walleye · February 25, 2007, 09:22:33 AM

Stu

I saw the picture of yours in the other thread.... Looks excellent!

I would probably run your auto tune again when you have more favourable weather. The wind and outside temp will definitely have an effect on the auto tune. I read on here somewhere, I think it was BubbaGrump, he would set the temp to 200. Then when it was at about 190 he would put 2 bricks on a rack in and turn the auto tune on. He said the 2 bricks would simulate a load in the BS.

Too bad about the weather, but keep me informed how you make out.

Mike

carnie1 · February 26, 2007, 05:02:19 PM

Hello
Been using a Guru/Raptor setup for 2 yrs now and am starting to have problems with it ,so I read until my eyes bled and built a PID from all the info I found here (you will notice this is my first post as I have been reading this forum for almost 3 yrs and never had a question till now) PID build went find, testing went fine , used autotune as best as I could make out how to do it, here are my readings after the 2nd auto tune (I knocked the plug out on the 1st one) everything is still on now Temp read on PID 201
Temp set on PID 200
P 624
I 472
D 384
Maverick reads 197
How can I tell which temp reading is correct? Maverick or PID?, I Am using Auber PID and Omega TC

Thank You

Mr Walleye · February 26, 2007, 05:14:11 PM

Hi Carnie1

Welcome to the forum.

I think I read a couple of different threads. One used boiling water to put the TC in as water boils at 212 degrees. The other one used ice water which should be 32 degrees. I haven't tried either one but I was planning on it. You may find the difference between them may have more to do with the placement of the TCs in the box. If you find it is the PID I believe there is a setting for it.

Mike

carnie1 · February 26, 2007, 05:56:06 PM

Thanks for the quick reply, there a probably a lot of variables here, I'm just trying to figure the right one, will do the boiling water , ice water thing for the Maverick tomorrow. Thanks again

@ NePaSmoker "Maroon and vite........ Maroon and vite.... those are the colors for vitch ve vite " I'm sure you'll understand this, we are probably neighbors I work out of that area, I'm not there now but will be back north in the spring.

carnie1 · February 26, 2007, 06:17:12 PM

Been about an hour and a half since my first post(someday I'll learn how to set forum times) and Mav reads 196 temp set is 200 and TC read is 202 , gonna shut it off now and give it another run tomorrow.

NePaSmoKer · February 26, 2007, 06:22:40 PM

Quote from: carnie1 on February 26, 2007, 05:56:06 PM

@ NePaSmoker "Maroon and vite........ Maroon and vite.... those are the colors for vitch ve vite " I'm sure you'll understand this, we are probably neighbors I work out of that area, I'm not there now but will be back north in the spring.

Carni1 I have not a clue ??? to what you mean. I am a newbie to the area (3 years) In PA for 9 years Lancaster County and am a S. Calif native. But anyways hi neighbor ;D

nepas

Habanero Smoker · February 27, 2007, 02:20:41 AM

Quote from: carnie1 on February 26, 2007, 06:17:12 PM
Been about an hour and a half since my first post(someday I'll learn how to set forum times) and Mav reads 196 temp set is 200 and TC read is 202 , gonna shut it off now and give it another run tomorrow.

Welcome to the forum. I've been using the Guru for about 2.5 year the only problem I've had was the TC. I pulled the wire out of the probe; my fault. Replaced the probe and every thing is fine.

As to the boiling point of water, other factors do play a role. Altitude and the current barometric pressure have and effect on the boiling point. Here is a site that will assist you in determining the boiling point for your location and weather conditions.
http://www.biggreenegg.com/boilingPoint.htm

If you don't know your barometric pressure use the default value they provide.

manxman · February 27, 2007, 03:29:49 AM

This is the method I use to check probes, tend to use boiling point rather than melting point as it better reflects the sort of temperatures we are using in the BS:

Boiling Point Method:

Bring clean tap water to the boil in a deep pan.
Put the thermometer stem or probe into the boiling water so the sensing area is completely submerged. Take good care not to scald yourself.
Do not let the probe touch the pan bottom or sides.
Wait 30 seconds or until the indicator stops moving.
The thermometer should read 212F, (100C) or the appropriate boiling point for your elevation. (see above)
If it does not fall within an acceptable range (+/- 5F/2C) the thermometer should be recalibrated according to the manufacturer's instructions, if indeed it can be recalibrated. Not all thermometers can be.

If the thermometer is under warranty it should be returned to the manufacturer.

If the thermometer is inaccurate, is not under warranty and/or cannot be adjusted it should be discarded. Any false reading at the boiling point of water may not be linear; i.e. it could be more (or less) inaccurate at different temperatures.

The boiling point of water is about 1F (0.5C) lower for every 550 feet (168m) above sea level but see the post from HS above regarding your location.

I check mine every 6 months.

Mr Walleye · February 27, 2007, 09:49:41 AM

ManxMan & Habanero Smoker

Great information and links guys!

Mike

Habanero Smoker · February 27, 2007, 02:06:26 PM

BigSmoker provided that link some time ago. It is very helpful. As a general rule, for my elevation, the boiling point is 110.9°F.

Tiny Tim · February 27, 2007, 02:23:07 PM

Quote from: Habanero Smoker on February 27, 2007, 02:06:26 PM
BigSmoker provided that link some time ago. It is very helpful. As a general rule, for my elevation, the boiling point is 110.9°F.

What the heck are you doing 10+ miles above sea level? ;) :D

iceman · February 27, 2007, 02:30:27 PM

TYPO; I think Hab meant 210.987654321 F ;D ;)
Either that or he's playing around in space again and not telling us. :o ;D

Fine tuning PID

NePaSmoKer