DIY PID Smoker Control W/meat Probe

I just built up a control for an electric smoker using a pair of AGPtech PID temperature controllers. This was set up for an electric smoker but could easily be used for a charcoal burner with the addition of a fan and 12vdc power supply.

One controller is used to control the smoker temp and the other to monitor the meat. A momentary switch SW2 is used to close a relay that completes the SSR control circuit to allow the smoker control PID to control the smoker. When the meat temp is reached the power to the relay drops and and interrupts the SSR control circuit and prevents the heating element from turning back on.

The smoker control PID was used in PID mode and set with autotune. On the meat temp controller P was set to 0 for on-off mode. Both controllers set to HEAT.

Tried it out yesterday and it works great.

Attached is the schematic in pdf format.

Let me know what y'all think.

bstomper said:

This couldn't have come at a better time. Im just gathering stuff for an electric smoker build. Whats the fan for, air circulation? How do you have it installed in the smoker? I want to do the same but was wondering how I was going to do it. I want it so it works similar to a convection oven and the temp is the same throughout the smoker. Just haven't figured it out yet. I also like the idea of 2 pid's one for meat and one to control the smoker. Do you have any pictures of the build.

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There is no fan if used for an electric smoker. You simply plug the electric heating element into the female electric plug and put the smoker temp thermocouple probe in your smoker. The control will simply turn the heating element on or off to control temperature. If used for a charcoal or stick burner you would need a fan to control the air to the fuel in order to control temp.

The meat temp probe is set up in this circuit to turn the system off when the meat gets to temp. If you just need an alarm instead of auto shut off it simplifies it a lot.

Will see if I can get pictures.

As far as a convection fan I hadn't thought about that. Will do a little research and see if I can come up with something. Could be pretty cool.

nickmv said:

If you've got a charcoal setup, you're probably going to be a lot better off building a HeaterMeter.

I've got one and they're great, and customizable to whatever setup you have.

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I'll probably end up building Heatermeter at some point. I like the way it works and the fact that it's open source hardware and software that you can hack on. The guy running the project is super too.

However, depending on what your goals and your level of expertise at electronics there are there are places that controls based on inexpensive PID temperature controllers can be a viable option.

bstomper said:

Thats prety cool. I have a charcoal UDS but I am going to use the PID for an electric build I am doing to smoke home made sausage

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Very nice setup. If you need any help with the PID controller let me know exactly what you are trying to accomplish and I'll fix you up. Are you needing just temperature control or do you want to monitor meat temp too? Do you want the smoker to shut down when the meat reaches temperature or sound or flash an alarm? How many meat probes do you need?

Give me those parameter and I'll get something worked up.

nickmv said:

Yeah for sure, PIDs can definitely get the job done if you're looking for a simple, inexpensive setup. The HeaterMeter is definitely not a cheap undertaking, as you're likely to spend 250-300 bucks. My favorite part of the HeaterMeter isn't necessarily the standard blower control features. It's being able to go out for hours at a time and never fearing any issues with meat cooking too fast. And the apps will show you rate of temp climb, and if things look like theyre going too fast, you can dial it back straight from your phone.

That's the part that sold me. It also supports servo controls, so I got a 3d printed blower contraption (rotodamper 3) that can starve the smoker of all air intake, which can rapidly tame a fresh refill of coals.

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You're preaching to the choir here as for as the Heatermeter. Nothing will do what it will do as well as it will.

A PID controller's place is where you need only specific features and don't need the full package.

There are multiple ways to take the pelt off a feline.

jabbey71 said:

Hey Rd, if I get the 1/8" mono headphone jacks for the thermocouple how many of the males and females will I need since there are two thermo wires.

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You are doing the one PID unit so all you need is one male and 1 female. You might want to get and extra male so you'll have it around in case you want to build up a spare thermocouple assembly. It's not a bad idea as they go bad occasionally.

If you bought this power supply:

[ame="http://www.amazon.com/Power-Adapter-Supply-1000ma-Quality/dp/B005JRGOCM/ref=sr_1_1?s=electronics&ie=UTF8&qid=1449061934&sr=1-1&keywords=12+volt+power+supply"]Amazon.com : 12v Dc Power Adapter Supply 2.1mm 5.5mm 1a 1000ma, Cctv *** Best Quality *** : Electronics@@AMEPARAM@@http://ecx.images-amazon.com/images/I/41K%2B4pxsWhL.@@AMEPARAM@@41K%2B4pxsWhL[/ame]

You might want to get this:

http://www.ebay.com/itm/5-5-2-1mm-L...977178?hash=item4aeaafea1a:g:gZ4AAOSweW5VYtOc

to attach to the fan.

bstomper said:

Thats awsome. Thanks. I will need the help. I have a maverick temp monitor but if I could control smoker temp, meat temp and auto shut off all with a PID or two, that would be great. A second meat probe would be a cool option also.

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No problem.

Let me know exactly what you need and I'll hook you up.

bstomper said:

Thats awsome. Thanks. I will need the help. I have a maverick temp monitor but if I could control smoker temp, meat temp and auto shut off all with a PID or two, that would be great. A second meat probe would be a cool option also.

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If you've never built any electronics projects before you might consider this. It looks like it will do what you want to do off the shelf.

http://www.auberins.com/index.php?main_page=product_info&cPath=14_28&products_id=381

bstomper said:

Thats awsome. Thanks. I will need the help. I have a maverick temp monitor but if I could control smoker temp, meat temp and auto shut off all with a PID or two, that would be great. A second meat probe would be a cool option also.

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Just downloaded a couple of manuals on the REX C100 PID controller you have. It has possibilities. Not sure if this particular unit will work in degrees F but will be fine if you are OK working with degrees C.

Will see what I can get together for you. A single PID control for the smoker should be no problem. Don't know yet about adding another controller with auto shut down based on meat temp.

bstomper said:

Thats awsome. Thanks. I will need the help. I have a maverick temp monitor but if I could control smoker temp, meat temp and auto shut off all with a PID or two, that would be great. A second meat probe would be a cool option also.

Click to expand...

Looked at manuals.

A single smoker temp controller with this particular REX C100 is doable.

A second controller for meat temp without alarm is doable or could get a different model# C100 that has an alarm for the meat temp. The model# on this one on the eBay picture designates an alarm but the pictures of the unit show terminals 6 and 7 are omitted and that's where he alarm relay terminals should be.

Can't do an automatic shutdown (at least the way I usually do it) because the C100 uses a 12VDC pulse output to the SSR and won't drive the coil of the small relay that I use to interlock the controls to keep the heating element shut down once the meat reaches the set temp. Without the interlock every time the meat temp drops below the set temperature then the heating element would power back up to full smoker set temp until the meat temp set point was reached again. If that's OK then no problem but that couldn't be a good thing have go on for a long period of time. The control I normally use can be programmed for an on/off 24VDC output that normally goes to a SSR but can be used to power the interlock relay. I'll see if I can come up with a different concept.

Not sure about whether this unit will do degrees F or not. There is a place in the programming for that function but don't know if this manufacturer has it enabled. It wasn't in the specs on eBay.

Attached is a diagram for a basic single controller for controlling the temp of an electric smoker using the REX C100. I just modified the diagram I had drawn up for the TA4-snr single controller I drew up for jabbey71

Let me know what you think.

Originally Posted by bstomper
Here is how I would like it to work.
Temperature control for the smoker and one meat probe that will power a small light when the desired temperature is reached. I don't want it to shut the heating element off just to power the light.

What kind of temp probes will I need for the TA4 controller

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bstomper:

attached is a diagram of a dual control unit like you requested using TA4-snr controllers with an indicator light alert for meat temp.

The TA4-snr uses the same type K thermocouple the REX C100 uses.
White wire (blue connector) to terminal 7
white/red wire (red connector) to terminal 8