After pouring over all the PID posts, I still have one question I need clarification on. It seems everybody talks about autotuning for one temperature (being their favorite temp for most of their fixin's) however, I have only found a few threads indicating people being able to keep the kind of control with the PID over say, 3 different temps over a single smoke.
For example, some of the cured summer sausage I have done requires 2 hours at 130 deg, 2 hours at 150 degrees, then a final cook at 170 until done. My questions are, what temp would I autotune for this process and, will it keep the same constant temp around a set temp of 130 as it would at 170 even though it may not be autotuned for these temps?
I was under the impression I could run out in just my underwear and big rubber boots this winter (as so often the occasion) to change water and press the up button on the PID to a new set temp. Currently I have to wake up an hour after each slider change to check the Maverick. Apparently the author of this recipe says these temps are a must for the ingredients used, but its a real challenge with the slider to control temps that tight. If I could hold +/- 3 deg. with a PID like most are reporting, but at EACH temp I might even skip the rubber boots this winter!
Thanks in advance for any input.
Have, Patience.
Hi Patience and welcome to the forum.
I did the auto tune with a butt in set at 210. I do see a little more varience in temps when doing things like jerky at say 170 degrees. The one thing I've thought about is if I record the P I and D settings then ran auto tune again at say, 160 degrees, I would probably end up with slightly different numbers. This way you could manually set the numbers, which is easy, depending on the temp range you are wanting. Currently I am +/- 1 degree in my usual temp zone of 200 to 220.
Mike
Patience,
Welcome to the forum. I do not have an autotune PID; I've built one from scratch and have manually dialed in the parameters. With that said, allow me to ramble.... :o
Since low temperatures can be obtained by the puck burner alone, and you do not control that, I would not tune with low setpoints. You are interested in optimizing the part you can control, and that is higher temperatures.
Another challenge (although I have not experimented with this) is that I believe the overall system response is tied to vent position. The thermal pathways through the sides of the box are fixed, but the vent represents a significant thermal pathway that can vary quite a bit. That complicates the PID control loop. Now, in the overall scheme of things, probably not a big deal. However, I figure I should probably investigate this for the next 10 years while sipping adult beverages.... :D :D :D
Arcs_n_Sparks
Hi Arcs
I still have a plan to semi-permanently mount my generator in a separate box. By doing this the heat plate on the generator would have less influence on the tower temp. At least thats the plan.
Gotta agree with you... more study is required! Better stock the beer fridge! ;D
Mike
Mr Walleye, I thought for sure your next few words after "plan to semi-permanently mount" was going to be "Kegerator". ;D
:D
Arcs_n_Sparks
Hmmmm! :D :D ;D
Mike
What in plain english is a PID and is it neccesary and are they easy to come by?
While I am here explane FTC please. :P
Hi BD
Here is link to the PID plans on Old's recipe site http://www.susanminor.org/forums/showthread.php?p=504#post504
The PID is an acurate temp control for the BS. Gives more of a set and forget setting that is usually + or - 1 or 2 degrees. There is a ton of posts on a number of variations but most are similar to the link above.
Mike
Quote from: bunnydude on April 29, 2007, 08:58:52 PM
What in plain english is a PID and is it neccesary and are they easy to come by?
While I am here explane FTC please. :P
Bunnydude,
Welcome to the forum. The PID is your
Porter
Indicating
Device. It tells you where your beer is. Some have morphed this to be a
Proportional,
Integral,
Derivative controller. This appears to be some E.E. invention to control your BS temperature. I built one, but still depend upon my adult beverage refrigerator for superior temperature control.
FTC is either:
Follow
The
Chicks or
Fill
The
Cup; depending upon your PID settings. Others will claim it means something like: Foil, Towel, Cooler (now that will make you drink). The theory here is to put your smoked gem in foil, wrap in a towel, and place in a cooler to further cook and/or remain at temperture until you have finished your beers and are ready for dinner.
At this point, more professionals will weigh in....... :D
Arcs_n_Sparks
Words to live by Sparkler :) ;) ;D
Coyote
Patience;
Welcome to the forum.
I don't know what type of sausage you are making, or how thick they are, but I found that using Jaeger's method of hot smoking sausage works well in the BS.
I modified the temperatures a bit lower. The temperature within the parenthesis are his. Preheat the smoker to 140°F (145°F). Place sausage in smoker, with vent wide open; dry the sausage for about 30 minutes. Close vent to 1/8 opening and apply smoke at this temperature for 2 hours. Next increase the cabinet temperature to 180°F (190°F), and if possible rotate sausage, at this time. I rotated the sausage one more time when the sausage comes within 10°F of the targeted internal temperature.
So basically, its harder to control the lower temps (just as I have found manually with the slider) but a PID would work better than the slider anyhow, though may not be +/- 3 deg. which I would love to get.
I did get an email from Auber within an hour of emailing on a Sunday night, now THATS impressive! I asked about the PID w/ramp and soak that you can program upto 30 different actions. I would be able to set as many temps and hold for as many hours making the process even more automatic. Thats too tempting!
I am trying to eliminate as many variables as possible including the venting. Putting the smoker in its own cabinet would cut out the wind and draft fluctuation I think thats a good start. Bottom line, just using the BS with no mods midwinter in a snow storm worked awesome. But, the grass is always greener so they say. Some babysitting is still required with a plain jayne OBS, but thats relative when you think about charcoal or wood fired smokers.
Have, Patience
Patience, welcome your PID questions and grass is always greener observation fits well with a significant number of the - just one more modification and I can make this smoker even better crowd here - I have not yet joined the mod squad but am sure it is just a matter of time. ;D ;D ;D
One question, ;) is it necessary to wear underwear if you are consuming adult beverage from a rubber boot and it is not winter time :) :) :)
:D :D ;D
Mike
I never did the autotune on mine and it always seems to hold within a few degrees of where the set point is no matter what temperature I have it set at, once it reaches it. Did I just get lucky? I did start the oautotune but got tired of waiting and just started using it. I have been very happy on how well the control has been, if the weather has been cold or hot when using it.
Mark
Thanks for the input guys! Now here is another thought. The PID I have has ramp/soak and 2 alarm outputs. I am assuming these alarm relays act as a switch. Current goes into 1 terminal and when the PID's directions tells it to switch, current exits the 2nd terminal to run just about anything you want. Does that mean I can hook a hot 120v wire in, and then feed the out terminal to the smoke generator motor? I don't know the specs of the input/output of the alarm relays yet, but I'm hoping that will work.
In other words, after say 2 hours of 120 deg. drying time, the PID ramps up to 140 deg. and when it hits 140 degrees, the alarm relay completes the circuit to the smoke generator motor and it starts smoking after a cycle or two of 20 minutes to feed the waiting pucks. After a programmed time you can tell the alarm relay to shut off, cutting the smoke. This would kind of be acting like the smoke generator switch Bubbagump put into his setup. Instead of a manual switch, the alarm switch will automatically start it and turn it off after a specified time. Am I climbing too far out on the limb of high thought here?
Don't think I'm being too lazy, there is a method to my madness as well as madness to my methods. Somebody with electrical experience please let me know if this is a go.
Have, Patience
Patience,
I do not have a ramp/soak PID with alarms. However, if your alarm function is a relay closure, then you can do what you propose (assuming the relay contacts can handle the load of the smoke generator). It is unclear to me how you time out the alarm condition and drop out the smoke generator.
If the alarm relay will not handle the load, it is pretty easy to wire in a relay that would take care of it.
Have you seen Mr. Walleye's setup using Schedule 80 PVC pipe?
Arcs_n_Sparks
Arc,
I have not seen the use of PVC, though I have read a few threads from Mr. Walleye when he was having problems with his SSR. Since then, searching under various subjects, your posts frequent many of them, thanks for sharing your know hows! From what I gather, the programable PIDs have commands to turn alarms on and off. 1=Alarm 1 on, 2 = alarm 2 on, 3 = alarm 1 and 2 on, 5 = alarm 1 off. etc.
If I understand it correctly it would take 3 commands to process the smoke. The smoke command turns the alarm relay on when temp reaches X degrees. The next command will hold X degrees for Y minutes while alarm is still on, aka smoking. After Y minutes the program goes to the next step, which will be the smoke off command. My only hang up is, once the relay is triggered for X degrees, what happens if X falls 10 degrees for some reason, will the alarm cut off, or will it wait for the alarm off command. Once I get the entire manual, if I post the specs of the alarm relays can you help figure out if I can run power through the terminals? ??? My head hurts, I'm going to bed!
I could just be talking out my ^&&, but it sounds good to me! :-\
Thanks in advance!
Quote from: Patience on May 02, 2007, 09:10:51 PM
Once I get the entire manual, if I post the specs of the alarm relays can you help figure out if I can run power through the terminals?
Yes, and I am sure there are others here that can help you out as well.
Quote from: Patience on May 02, 2007, 09:10:51 PM
My head hurts, I'm going to bed!
Take two Jack and e-mail me in the morning. :D :D :D
I took two aspirins, alcohol and I don't like each other. ;D Anyhow, I did more thinking on your question. I'll just have to wait until I get the book and try and figure things out.
The alarm output says 120VAC/3amp, I have no idea what the puck advance motor pulls. It looks like I can create a command in one of the 30 available steps to shut alarm on/off at will, rather than have it triggered by temperature. It would of course be triggered by temperature and shut off with a command. I don't think you can shut the relay off other than letting the temp drop below the trigger temp minus the deviation, other than the simple off command.
Have, Patience
They used to have .pdf versions of their manuals available but I don't see them on their web site now. You should shoot him an email. I'm sure if he has the manual in .pdf format he will sent it to you. That way you can study it before it arrives.
Mike
Thanks 'eye!
I got the pdf files, he emailed me back so fast, I thought it was an error return mail for a wrong address. Anyway, it looks like the ramp/soak PID Auber sells does have on/off commands seperate from temperature triggered alarms. I think this will work as I have explained earlier by completing the puck advance motor circuit. I still would need the programable PID to automatically step up the set temp over several hours as some of the recipes call for. As far as the automatic smoke idea, I havn't checked my Bradley, but somebody in this forum says they have to hit the advance button atleast once before it will advance every 20 minutes. If that is the case, this idea will not work as easy as I thought. I have always hit the advance button so I don't know if the motor will advance or not until the button is pushed atleast once. Any thoughts?
I was just thinking also, the damned damper still needs to be closed half when the smoke starts. I will have to sweet talk the wife into running out and turning it if I'm at work. I think as long as all she has to do is change the water and turn the damper, we're in business. I'll have to turn on the charm the day (and especially night) before smoke day! ::)
I have been reading this forum everynight and I am chomping at the bit to do all this stuff. I think I'll have to just take it a step at a time though, get the PID working, find a good tune and get things consistent before moving onto the autosmoke thing. Thanks for everybodys help!
It sounds like you have the OBS? If so I'm not sure about how the advace works because I have the DBS. I'm sure someone will chime in.
Keep us up to date on your projects. I'm always interested in tinkerin'! ;D
Mike
Quote from: Patience on May 03, 2007, 01:35:46 PM
I was just thinking also, the damned damper still needs to be closed half when the smoke starts. I will have to sweet talk the wife into running out and turning it if I'm at work.
Sounds like it is time to design a stepper motor arrangement for vent control... 8)
Got a few in the garage to play with. Thank goodness they are next to the adult beverage refrigerator.
Patience, I have no clue what the heck your'e talking about ??? but that's okay, I think I don't want to trouble my fragile mind right now :) by the way, plugged my beer fridge in this aft and have been diligently testing the product for optimal temperature.... fallen soldiers all about me, but I'll get it done.
I have an OBS, a PID, autotuned it under load (a butt fours hours in), and have the BS stored away in a BS shack I built and I use a Maverick ET-73. It runs as good as I can imagine. I try and have a beer every time I need to rend to the BS so whatever you plan on doing, make sure you need to tend it occasionally. :D
By the by, FTC'ing really takes whatever you've done and takes it another level entirely.
If I drank a bev everytime I tended the unmodified OBS, you'd find me puking behind the doghouse. Last time I drank a beer was the half that was left over after making brats one night back in 2003 (no kidding!).
I like the idea of the cabinet. That will tame the swinging Michigan weather and thats definitly next on my list. What my final plan is, to be 20 miles out into Lake Michigan trolling for salmon and tell the guys while looking at my watch, "Well boys, temps up to 140 and holding, and the smoke is starting to roll right about now" all the wife has to do is change the water and turn the damper. Next year I think I'll make a go at automating those as well....we'll see! :)
Oh yea, FTC will still be final step. In fact, if I get good enough at anticipating time to target temp of meat, I will actually incorporate atleast 2 hours of FTC into the final equation.
Listen to me, I havn't even been delivered all my PID project parts yet!!!!
;) When you do get the wife automated please post the results ... saw a movie about that once but still have not get in figured out ;D
Quote from: Arcs_n_Sparks on May 03, 2007, 05:50:27 PM
Quote from: Patience on May 03, 2007, 01:35:46 PM
I was just thinking also, the damned damper still needs to be closed half when the smoke starts. I will have to sweet talk the wife into running out and turning it if I'm at work.
Sounds like it is time to design a stepper motor arrangement for vent control... 8)
Got a few in the garage to play with. Thank goodness they are next to the adult beverage refrigerator.
Okay, doing design work next to the adult beverage refrigerator was not a great idea this time around. :o
Ended up letting the smoke out of one of the stepper drive I.C.s when I "fired up" the circuit. This is
not the smoke you want to see. However, the beef sticks I made today came out great, so I came out even for the day.
Arcs_n_Sparks
Ozone bisquettes? You may have stumbled onto a new flavor for Bradley to offer Arc, you may get rich! Sorry about your stepper, did the motor burn? I ran your idea by a guy who went to school for this sort of thing, and he said I'd be better off hiring a high school student looking for a summer job as a full time damper turner, for those types of motors can get expensive?
Atleast you saved the beef! Keep upright, and get back to us on the automatic damper turner thinger that may cost a lot for what it does, but thats not the point!
Have, Patience
The stepper was fine; I toasted the driver for it. Like an idiot, I didn't limit the supply current... >:(
Got the stepper out of an old printer (that is where a lot of surplus steppers on the web come from). My goal is to not have any accessory that costs more than 25% of the Bradley.
Arcs_n_Sparks
Hope you figure the autovent out your next go!!
I put my PID project together today minus the TC I have to wait a week for. It fired up and it reads the max temp w/o the TC, but I played around with the buttons and you could hear the alarm relay click on and off as I changed the value. I still havn't looked in the smoke generator to see how many amps the puck advance motor requires. Do you know?
I did not use a heat sink, though I did smear some silver compound on the bottom of the SSR and mounted on the large aluminum plate that comes with the project box. I remember somebody in a different post suggesting this and is seemed like a good idea. Its a 25amp SSR and from what I can tell, nobody has a heat problem even with the smaller SSR. I think it'll be OK.
Concerning your stepper motor, what is the driver? How would you tell it how far to move the damper? THanks!
Patience
patience,,
if you wire in a contact relay { same voltage as power to PID } you can run wires to the smoke generator useing some ? bannana plugs ? { think thats what they were called } and bypass the "on" switch in the gen. you will still have to plug in the smoke gen as usual , but then you can use the alarms on the PID to turn on and off the smoke.
gen with pugs to conect to PID
(http://img474.imageshack.us/img474/1342/sgcontrolhookupsen0.th.jpg) (http://img474.imageshack.us/my.php?image=sgcontrolhookupsen0.jpg)
chris
Quote from: Patience on May 07, 2007, 01:09:58 PM
Concerning your stepper motor, what is the driver? How would you tell it how far to move the damper? THanks!
The driver was a demo board from Microchip (PICDEM). Has on-board logic and FETs. Used to evaluate both brushed DC motor control and stepper motor control. The board has overcurrent protection, but my failure was hooking up a 13.8V supply to what was suppose to be a 12V max. input.
Most steppers go 7.5 degrees/step. With a toothed belt and appropriate gear on the vent, it is pretty easy to calculate the number of steps from full open to full close.
Arcs_n_Sparks