PID or BBQ Guru Raptor and Competitor Pkg.

TomG · January 25, 2006, 05:21:51 PM

Earlier in this thread I suggested the rheostat probably had little affect on temperature fluctuations when a thermostat controlled the oven, and that if there was any interest in duplicating Norbert's installation, there would be next to no down side replacing the slide, in the panel, with a TS. I was speculating that because the cooking element had so little weight(mass) that it would be a poor heatsink and would not retain enough residual heat to be a problem.

Bubbagump responded; <blockquote id="quote">quote:<hr height="1" noshade id="quote"> Not a good idea to remove the temperature slider for two reasons. First, leaving it in place will allow more control over temperature swings. Second, removing it will render your BS useless if you have any problems with your controller.<hr height="1" noshade id="quote"></blockquote id="quote">

Oldman offered; <blockquote id="quote">quote:<hr height="1" noshade id="quote">The elememt if all the way to the right when on is much hotter than say at mid-range. Thus it will take it longer to stop heating up the unit.<hr height="1" noshade id="quote"></blockquote id="quote">

The Question: Will changing the rheostat output effect temperature swings and if so how much?

Setup:

My BS with a Coldfusion PID used as a K thermocoupled digital thermometer. The oven was empty, the damper was 1/3rd open, and the ambient temp. was 64*(Yeah, eat your hearts out!)

Method: The temperature was controlled with a very dumb switch(yours truly), I pulled the plug on the upswing when the thermometer reached 200* and put the plug back in when it hit 200* on the downswing. I repeated that routine for 3 cycles for each of the slide settings (1 ½" and 2" from the left sided off position), recorded and charted the results.

Results:

Calibration of a spare BS rheostat suggested that 70% of control was in the last 1" of slide travel and in the far right position it was delivering only 93% of available current.

The average temperature swing with the slide at 1 ½" was 196*–202*. At 2"(all the way to the right) it was 196*-207*. Initially, at 1 ½" it took 27 minutes to reach 200*, but only 12 minutes with the slide at 2". It then took an average of 6 minutes and 3 minutes respectively to get back to 200* when the heater was cycled.

Bottom line: In my BS, using only the cooking element as a heat source, with a target temp of 200*, the temperature swing at 2 different slide settings (1 ½" and 2" to the right) where the output at the lower setting was approximately 70% of the higher setting, there was a measurable, but minimal difference in temperature swings ie; 196-202* at 1 ½" versus 196-207*.
However there was a very significant difference in the time it took to get to the target temp. From an ambient temperature of 64*, it took 27 minutes to reach target at the 1 ½' setting and only 12 minutes at the 2" setting. The comparable times for cycling was 6 and 3 minutes. At the maximum slide setting you can expect a few degrees increase in swing, but for me, that would be more than offset by a much shorter lag time to heat the oven.

As far as Bubba's 2nd reason for not removing the rheostat; <blockquote id="quote">quote:<hr height="1" noshade id="quote">removing it will render your BS useless if you have any problems with your controller.<hr height="1" noshade id="quote"></blockquote id="quote">

Owrstrich's experience; <blockquote id="quote">quote:<hr height="1" noshade id="quote">my sliders never lasted long enough to get an accurate assessment of the situation<hr height="1" noshade id="quote"></blockquote id="quote">... suggests that a spare might not be a bad idea even if you don't install a thermostat.

Bubbag, the swing difference was more than I thought it was going to be, so I owe you a 12 pack of Bisquettes in flavor of your choice as longs as it's Special Blend.

bubbagump · January 25, 2006, 09:33:20 PM

Nice work TG!

For those that use the TS with the rheostat, as Olds mentioned earlier, leave the rheostat all the way to the right when preheating and after placing meat in the BS. This will allow the box to come up to temp. much faster. After the temp stabilizes a bit you can back off on the rheostat to help minimize temp swings.

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Bubbag, the swing difference was more than I thought it was going to be, so I owe you a 12 pack of Bisquettes in flavor of your choice as longs as it's Special Blend.<hr height="1" noshade id="quote"></blockquote id="quote">
No payment necessary TG, I've really enjoyed this thread.

It will be interesting to see what results Owrstrich comes up with.

Thanks TG,

Bubbagump

IKnowWood · January 26, 2006, 12:15:08 AM

I also am holding on my order for the TS till next week to see others experience. And more info on the programming.

drano38 · January 26, 2006, 12:46:53 AM

Phone Guy,
I think I have +/- 3 degrees set on mine--can't tell right now because I have the wires off and moving it into a Radio Shack project box, and don't have power wires hooked up yet.
I used it once before my rewire project. I was doing 5 three lb sticks of summer sausage and the temp did not come up to 168 deg until the meat almost got there and I was done, so I don't know how well it will hold temp, or how big the swings are.
I'd guess +/- 2 or 3 should be OK. The PIDs will do better than that, but don't know if it really matters. For me, $50 and simple setup works great. Others who like setting up electronics will enjoy the PID.
Drano

TomG · January 26, 2006, 04:51:07 PM

Just in case it isn't common knowledge, a Dremel with a cutting disc works great for cutting holes in the plastic sides of the project boxes.[:)]

IKnowWood · January 26, 2006, 06:04:13 PM

As is a reversed mini-saw blade. Makes a heck of a mess thou.

You can also use the dremel quick cut bit that cuts side-ways.

bubbagump · January 26, 2006, 07:00:53 PM

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by TomG
 Just in case it isn't common knowledge, a Dremel with a cutting disc works great for cutting holes in the plastic sides of the project boxes.[:)]
<hr height="1" noshade id="quote"></blockquote id="quote">
Yep, I second that. I installed my PID in my smoke generator and used a dremmel for that as well. Worked great.

Bubbagump

owrstrich · January 27, 2006, 07:16:55 PM

this is how i wired the ts13010 switch...

went 3 prong male cord out of back of smoke generator into switch... went switch out to 3 prong female into back of bradley...

the switch is simply like pluging and unpluging the bradley power cord... i made sure it was making and breaking and all is well...

tonight i have about 40 pounds of beast going in... gonna set the switch at 200 deg and 1 deg differential... will adjust as necessary to get temp and diff proper and report back here...

thanks for all the input folks... now i wish i could have found a box fot the switch but no go so far... any ideas...

owrstrich

TomG · January 27, 2006, 08:48:48 PM

Ow, here is what I use:

http://www.radioshack.com/product/index.jsp?productId=2062284&cp=2032058&f=Taxonomy%2FRSK%2F2032058&categoryId=2032058&kwCatId=2032058&kw=project+box&parentPage=search

owrstrich · January 28, 2006, 12:44:41 PM

13010 performance... contains five updates...

heres what i gotts... ill set it up for you... i gotts 3 rack to a full load... 12lbs pork on bottom... 5 lbs corned beef next to bottom... 12lb brisket next to top.. 1lb layer of bacon on top...

13010 probe in middle... between next to top rack and next to bottom rack... 73 probe same...

70 deg no wind... venting with fan and duct... vent 1/4 open... slider all way right... puck burner on...

13010 reads 200 the 73 probe reads 204.. 13010 probe reads 191 the 73 probe reads 195... gotts 2 deg each way i guess...

first update...

started unwarmed...40 deg internal... now fully warmed at 200 deg and 60 deg internal... fan on...

2 deg diff option...

200 deg 2 deg diff... cut out at 200... 1 min later temp only goes to 201 and starts falling... 1 min later its at 197 and ts cuts in... temp falls all way to 191 in 4 min then starts rising back to 200 in 6mins...

200 deg 2 deg diff = cycle is 12 mins and has a 10 deg temp swing before cutting out again...

1 deg diff option...

200 deg 1 deg diff... cut out at 200... 1 min later temp only goes to 201 and starts falling... 1 min later its at 198 and ts cuts in... temp falls all way to 193 in 3 min then starts rising back to 200 in 5mins...

200 deg 1 deg diff = cycles is 10 mins and has a 8 deg temp swing before cutting out again...

second update... 200 deg and 145 deg internal... fan on...

i pulled the pork at 145 internal and now just have to 2 briskets and the bacon... no change from above being loaded 12lbs less from 30lbs to 18lbs... with briskets at 140 internal...

ill bump it and stick with 203 temp and 1 def diff for now... im thinking thats giving me real 205 high and real 197 low approx average 200 to 202 deg... thats wonderful...

tom... my set up will look the same when i get it in an enclosure... i got the enclosure last night at frys electronics but will not be able to cut the holes until tomorrow... im using the same electrical plugs and just have it sitting on top the bs right now for its first go...

third update... 203 deg 160 deg internal... fan on...

gump...

info above was 7 hours in... briskets were at 140...

right now im 14 hours into it and the briskets are at 160 deg...

i bumped the ts to 203 at the 7 hour mark in attempt to get a 200 average...

right now... 203 deg 1 deg diff... cut out at 203... 1 min later temp only goes to 206 and starts falling... 1 min later its at 201 and ts cuts in... 4 min later temp falls to 195... then starts rising back to 203 in 10 min...

203 deg 1 deg diff = cycle is 16 mins and has a 11 deg temp swing before cutting out again... 205 high 195 low... 16 minutes rise and fall for approx 200 average...

note... i turned my fan off for a few minutes and noticed rise to fall for approx 200 average was 12 minutes compared to 16 with the fan on... my fan maybe a little too strong for my relief holes... but i have to move enough air to overcome the prevailing winds hitting the window without smoking up the place... just one of those deals...

fourth update... 203 deg 185 deg internal... fan off...

right now... 203 deg 1 deg diff... cut out at 203... 1 min later temp only goes to 208 and starts falling... 1 min later its at 201 and ts cuts in... 3 min later temp falls to 198... then starts rising back to 203 in 5 min...

203 deg 1 deg diff = cycle is 10 mins and has a 10 deg temp swing before cutting out again... 208 high 198 low... 10 mins rise and fall for approx 203 average...

so... it appears the hotter the meat the more overshoot after cut out with the same amount of fall relative to the meat temp... all in all i like the unit cause i know i can set it at 203 deg with 1 deg diff and can avarage approx 200 to 203 depending on meat temp...

fifth and final... 203 deg 190 deg internal... fan off...

im 20 hours in and the only thing left in the bs is the 12lber and its coming out... i noticed higher than normal temps between 185 and 190 internal...

right now... 203 deg 1 deg diff... cut out at 203... 1 min later temp only goes to 213 and starts falling... 3 min later its at 201 and ts cuts in... 3 min later temp falls to 200... then starts rising back to 203 in 3 min...

203 deg 1 deg diff = cycle is 10 mins and has a 13 deg temp swing before cutting out again... 213 high 200 low... 10 mins rise and fall for approx 206 average...

im out... the corned beef has been ftc for 5 hours... gotts to go try it... the 12lber was on top for 15 hours and took 5 hours longer than the 5lber...

for $49 unit... $8 shipping... $10 other supplies... $67 total for all...

thanks to everyone who has posted on this thread as well as others who posted their analog and digital set ups on other threads over the last couple years...

owrstrich

here is a photo of the love controls technician who came out to program the 13010...

i told him the bs needed to remain vertical and not to put that computer under it... but he had duct tape... i was ok with that...

bubbagump · January 28, 2006, 01:15:01 PM

Hi Owrstrich,

Out of curiosity, how far into cooking where your readings taken?

Bubbagump

bubbagump · January 29, 2006, 02:57:42 AM

Thanks for the updates Owrstrich.

With the tests you and TomG have done, along with the pictures, it should give anyone who's uncertain whether they want to buy the TS all the info they need to decide.

Thanks again.[:)]

Bubbagump

IKnowWood · January 29, 2006, 12:53:00 PM

Sold!

I am ordering one and built my own setup. For the price, its worth getting, if only to reduce the amount of time I need to go out and adjust that slider. Thanks for the detail Owrstrich and TomG. and Owrstrich, what picture. I am also curious which programming parameters you setle are your best bet.

owrstrich · January 29, 2006, 03:33:30 PM

wood... its a simple temp activated on/off temp switch... you will have it programmed in 60 seconds... the only thing i changed was temp range from factory to -50 and 300... diffetential from factory to 1... set point from factory to 203...

social distortion...

owrstrich

TomG · January 29, 2006, 05:38:12 PM

Maybe a certain "Sacred Cow" chip should be the next mission impossible? [}:)]