PI Controller project

[JC in GB]

Good day all. Not sure if anyone is interested in this but I have been working on a PI controller design for use on a charcoal smoker. My point to this was to evaluate if an analog PI controller will regulate smoker temp as well as a digital PID controller. My testing up to this point has been promising but, as with any design work, I have had a few setbacks. If all goes well, I think I can produce a controller that will regulate a charcoal smoker as well as a digital PID controller for around $10. I have attached a picture of my breadboard design test circuit. The circuit consists of a PT-100 temperature sensor input amplifier, an analog comparator stage, an integrator stage, and the output driver stage. Right now, I have started working on the output driver but have been having some headaches getting it to switch on at the right point. If you have made it this far, thanks for looking. I am very close to building the working prototype and testing it on my smoker.

JC

 

[forktender]

That is awesome Jeff, I have no idea what I am looking at, but I want to be one of your test subject. It would be really cool to hook one up to my weber kettle, with a rotisserie on it.
Keep at it bruth'a, I know you'll get it dialed in.

 

[mr_whipple]

Looks interesting. I've grown lazy in the last few years with my new job and do absolutely no component level work anymore. Following!

 

[dsk]

The original PID controllers were pnuematic, and transitioned to analog electric before being implemented with digital circuitry.

 

[Fueling Around]

Too cool man.
I am not good with electronics. I'm on the power side with good old A/C. Pretty good for a (tired) mechanical engineer.

 

[Fueling Around]

The original PID controllers were pnuematic, and transitioned to analog electric before being implemented with digital circuitry.

I'm from the age when a lot of controls breadboard design began with pneumatic.
A few years later controls were digital that needed A to D translators.

 

[bigfurmn]

To quote Honer Simpson "uhhh can you repeat the whole part where you talked about the stuff?" Sounds cool of it understand it right.

 

[hoity toit]

Too cool man.
I am not good with electronics. I'm on the power side with good old A/C. Pretty good for a (tired) mechanical engineer.

Me also,,,Master Electrician for 40 yrs.

 

[JC in GB]

Just wanted to provide an update to the PI controller project. After getting my last two issues fixed, the bias point of the output comparator and the fan driver output, I am ready to put this circuit down on a protoboard and then test it out on my smoker. In the past, if I needed a comparator, I would use a chip that was designed for being a comparator. I wanted to keep this design simple and use only one IC for the whole thing so I chose a TL084 quad Op Amp. The TL084 is a good quality Op Amp, is readily available, and inexpensive. I will upload a pic once I get the circuit down on the protoboard. Thanks for following and please wish me success.

JC

 

[02ebz06]

Looking forward to seeing the finished product.

 

[normanaj]

Apparently I missed this post the first time around. Following for sure.

 

[Up_In_Smoke]

Just wanted to provide an update to the PI controller project. After getting my last two issues fixed, the bias point of the output comparator and the fan driver output, I am ready to put this circuit down on a protoboard and then test it out on my smoker. In the past, if I needed a comparator, I would use a chip that was designed for being a comparator. I wanted to keep this design simple and use only one IC for the whole thing so I chose a TL084 quad Op Amp. The TL084 is a good quality Op Amp, is readily available, and inexpensive. I will upload a pic once I get the circuit down on the protoboard. Thanks for following and please wish me success.

JC

TL084's are pretty good op amps.

And don't forget the old 555 that just won't die.
I swear you can do anything with one of those. :)

I still have the old 555 Handbook.
A little worse for wear.

 

[SmokinEdge]

Exiting. Am following.

 

[JC in GB]

TL084's are pretty good op amps.

And don't forget the old 555 that just won't die.
I swear you can do anything with one of those. :)

I still have the old 555 Handbook.
A little worse for wear.

I have used many a 555 timer. I even used one for a PWM driver. That is some old but reliable tech right there.

 

[Up_In_Smoke]

I have used many a 555 timer. I even used one for a PWM driver. That is some old but reliable tech right there.

Yeah, they could source or sink 200mA back in the day.
Not sure what they'll do today.

 

[JC in GB]

Yeah, they could source or sink 200mA back in the day.
Not sure what they'll do today.

LM555 can source 200 mA at 15 VDC. Some of the newer ones can only sink 100 mA. The TI LMC555 DSBGA package is only 1.5mm x 1.5mm. Unreal...

JC

 

[radioguy]

Hey take a look at schematic for Heatermeter. I built one a few years back. Not sure what comparator he used. But maybe it'll help you out. I built ver 4.3 still working today. don't use the wifi just as a PID.

RG

CapnBry - Overview

Bry as in BRYAN, get it?! CapnBry has 46 repositories available. Follow their code on GitHub.

github.com

 

[JC in GB]

Hey take a look at schematic for Heatermeter. I built one a few years back. Not sure what comparator he used. But maybe it'll help you out. I built ver 4.3 still working today. don't use the wifi just as a PID.

RG

CapnBry - Overview

Bry as in BRYAN, get it?! CapnBry has 46 repositories available. Follow their code on GitHub.

github.com

Thanks. I will check this out for sure.

JC