Temp Variance DBS Auber PID

[Mountaineer]

In a separate post I detailed a mod to my DBS. Added second 500 watt element, purchased dual probe Auber PID.

- Ribs are my first test today at 24 degrees ambient temp.
- Preheated DBS to 232
- Placed 3 shelves of racking with two rib sections per rack in smoker.
- Placed Auber cabinet probe between upper and second rack in the center with alligator clip.
     Left middle section of racks open with no ribs so I could place temp probe and not get drippings on it 
- Cabinet temp dropped to 170 after opening and placing ribs in
- 45 minutes later I took the photo below (Could not get the photo inserted). DBS temp 275 degrees. Auber probe 221

Given my target temp is 232 for the ribs and that the DBS would heat up to about 20 degrees above that target temp, it would have shut off the elements with the true cabinet tempurature around 180. Over time and as the meat temp increased the variance would likely decrease.

It took 1.5 hours for the smoker to get to back up to temp (232) after putting ribs inside. The ribs had been out of the fridge and being prepped for about an hour prior to putting them in.  This is with the dual element upgrade.

At maintenence mode (Full temp) The temp variance continues to be 51 degrees.
Auber probe 232, DBS  283.  So to smoke at 232 I would have needed to have my DBS on 283. Now I now why my smoking times were SO much more than others. I was really smoking low and slow!

[devo]

The only thing different I do is clip the probe to the bottom rack but you seem to be doing OK.
This might help you out with your picture posting trouble


http://www.susanminor.org/forums/showthread.php?488-Answers-To-Bradley-Smoker-FAQ-s&p=768#post768

[tskeeter]

Mountaineer, did you run autotune on your PID after you added the second heating element?  As shipped, the Auber PIDs are set for the standard single element smoker configuration.  If you run autotune with a couple of bricks in your smoker (to simulate a heavy load of cold meat) your PID will learn how fast you smoker heats up and will adjust itself to optimize the temperature control.  Note that there is also a setting that tells your PID that you are running two heating elements.  Changing this setting will allow the PID to ease up to the temperature set point more gradually.  Sorry I can't give you explicit instructions how to do that right now (at work).  But, your PID owners manual tells you which setting to change and how to change it.

[Habanero Smoker]

You should also follow Devo's suggestion of placing the probe underneath the bottom rack, away from the meat. When you place it between racks you will get a lower temperature reading. Your bottom rack is probably being expose to temperatures over 250°F. That is alright, but those ribs on the bottom rack will cook in about 4.5 hours.

When I cook ribs in the Bradley I will rotate the racks, and never had all the racks finish at the same time.

[Mountaineer]

tsk,

I reset the P value per instructions from a thread on this forum. GusRobin posted this in the acessories section of this forum, "You can autotune if you want to but the Auber PID is pre set for the single element Bradley. If you have the dual element the "only parameter you need to change is the P value. It should be increased from 70 to 140. The rest of parameters should be kept the same as the original (I=600 and d=150).  This will give you the best result." that is a quote from Suyi at Auber."

Some instructions for use are posted here
http://forum.bradleysmoker.com/index.php?topic=18346.0


I followed these instructions and the highest variance from target temp I noticed was a 4 degree swing. In other words, I had the Auber set to 232 and the highest tempurature I observed was 236 while it was smoking.

The auber made a huge difference in cooking times. The ribs were at 175 degrees internal temp in 4 hours. They were baby back ribs not spare ribs.

[Mountaineer]

Devo and Hab,

Thanks for the insight that helps me improve results. That explains why the ribs cooked more quickly than expected.

So the cabinet probe should be below the bottom rack of meat and off to one side, correct?