DIY automatic temp controller for my UDS

Obviously, I like to tinker and build stuff since I built a UDS. So, I thought I would give it a shot at building an automatic temp controller. Here's what I've got so far:


This is the Auber Instruments Universal 1/32 DIN PID Temperature Controller, 12 VDC. I mounted it in an aluminum housing that I was able to get out of a scrap bin at work.


This is the rear of the housing. You can see the connections here. I originally tried using a banana plug setup for the thermocouple, but found I was getting very inconsistent measurements. I decided to do away with the banana connector and run the thermocouple directly to the PID inside the housing.


Here's the connectors labled to see how where everything is connected.


This is the blower fan assembly. This is simply a computer CPU cooling fan I had lying around the house, installed in a plastic hobby box. I have a 1/8" mono headphone jack on the side that is used to connect to the PID controller assembly. Also, it has a 3/4" nipple that will screw directly into the ball valve of my UDS. I need to find a fan grill to cover the fan....


This is the cable I made using 1/8" mono jacks to connect the blower fan assembly to the PID controller assembly output.


Here it is all connected.


This is the power supply. It is overkill, rated at 4 amps. It is an old laptop power supply I had lying around, it's free, so I used it.

If you want to see a demo video of it in action, go here:
http://www.youtube.com/watch?v=DyK2Ga9TefA&list=UUSvrDenEHxeYFGBls1uyQBQ&feature=share

Now I need to mount it to the UDS and give it a try to see if I can get it "dialed in". More to come when I get it going on the UDS.

I've got a little less than $80 for everything. Of course, I did have some of the stuff lying around so that saved some money. The PID was $37.50, the thermocouple was $20, I spent about $20 on connectors, etc. You can get thermocouples for much cheaper if you shop around.

ebijack said:

Very nice! Any plans on making an adjustable fan cover? Just incase the CFM are too much for real low and slow smoking. Just curious.

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I will install it to (above) the ball valve, I can control intake amount by adjusting the ball valve. That will also make it easy to remove if I don't want to use it. It will go here:

Pyrotech said:

do you have a schematic showing how you wired up everything

Click to expand...

I will draw up something for you. Stand by...

Here is the schematic. There are two options. Auber says you can connect the blower fan directly to the PID controller or use an external SSR (solid state relay). They say it will "last longer" if you use the SSR.

I used my DIY ATC this weekend. It worked great!





My UDS was ALMOST set it and forget it prior to using the ATC. The ATC gives me confidence that I can leave it unattended for an extended amount of time without stressing out over temp control. Yeah, I know the purist are cringing. :heh: For my first cook I closed all other vents and connected the blower fan to one of the three vents behind a ball valve to be able to shut things down when finished. See above.




Here is a shot of it all connected and the controller resting on one of the handles. Last night I started on building a tray to place the ATC during the cook.




If you look at my original posted pictures, the thermocouple was connected internally to the controller. This would not allow disconnecting the thermocouple from the controller. So, I installed a thermocouple connector from Auber so I can easily disconnect the thermocouple from the controller. I also added a power switch. See above for the updated connections.


Well, I'm very happy with how it turned out and I ended up with less than $100 in everything. Let me know if you guys have any questions. I'd be happy to help with any tips and advice that I can from my experience.

PDPatterson

CakeM1x said:

Is this pretty much light some coals, attach pid and walk away? Would definitely be nice for the cooler months for controlling the heat.

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That's the idea. Worked great on the first run.

THoey1963 said:

As I mentioned above, I have a PID from Sous Vide cooking. I bought the appropriate thermalcouple from Auber. Now all I need is the fan / air source and a connector to mount to my WSM. Any ideas where online to order just a fan and a mounting bracket for a WSM pinwheel vent? I have tried looking, but my Google-Fu is failing me...

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It depends on how cheap you are and how much you're willing to fabricate. Here's a simple solution: I'm guessing that your PID controls a 110VAC output, is that correct? If so, you would plug a 12VDC adapter into the PID controller. Then, you would splice the wires from the 12VDC adapter to a blower motor (not requiring connectors).

Auber sells a blower, but it is not made specifically for WSM for $59, but will attach to it. It is here:
http://www.auberins.com/index.php?main_page=product_info&cPath=14_27&products_id=344





Here's a picture from Auber's website mounted to WSM:


Then, all you would need is a 12VDC wall wart power adapter. You could probably get this at Radio Shack, maybe Walmart, Best Buy or Ebay/Amazon. You would need to splice wires from the power supply to the blower. Here's a picture of what I'm talking about:



You can buy blower fans cheaper on Ebay, but most of them have to ship from China. Hope this helps out.