With the onset of nice weather I was wondering if anyone had resources for automating a 600 degre...

[G+_Jason Perry]

With the onset of nice weather I was wondering if anyone had resources for automating a 600 degree propane poweres box.

[G+_Eddie Foy]

BBQ/Smoker?

[G+_Jason Perry]

Its a BBQ. An old one so if I brake it or do a poor job its okay.

[G+_Jason Perry]

I would like to put temp sensors on or under the covers over the burners and replace the valves with solenoid. I all ready have one valve that is busted so I would start there and once it works move on.

[G+_Jason Perry]

Only how do you make something to work in those conditions

[G+_Eddie Foy]

I do industrial controls (PLC and such), so I tend to trend that way.  But.....

 

Temp control is a normal process.   For a BBQ I'd keep it ultra simple.

I'd use a bi-metal vent(s) (like the old school carburetor  automatic chokes) to let off excess heat, and use a manual valve to set a base point of the propane.

 

Set the vents to a temp (would need run tests to find the points for vents and propane setting) and the propane to a spot where vent just move.

 

Electronic/Arduino control is possible but overkill.  I might use one for too cold/hot alarms via  a K-Type thermocouple with amplifier > electronics.  (or just one of those wireless BBQ alarms.)

[G+_Ben Reese]

At 600°, I can seem to find many contact options for temp sensing. Closest solution I could think of was an IR temp sensor that could be read by an Arduino (MLX90614). Since that would have to go outside the grill, you would probably want to experiment a bit to see which point gives the most accurate reading (or use multiple sensors and take the average).

 

Seems like you could use a solenoid after that to control gas on/off, but you would probably also want a solenoid that had variability instead of just open/closed.

[G+_Eddie Foy]

proportional solenoid valves are pricey.  Also think of the safety involved with using propane.

[G+_Eddie Foy]

A servo or stepper motor on the control valve might work.  But I'm still concerned with safety.

 

Feel its best to set the propane manually to a little over desired temp and manipulate the vents to control temp.

[G+_610GARAGE]

To control the temperature electronically, I would suggest a two stage burner. Basically have two solenoids per burner. Set it up so that one solenoid has low flow, and the other solenoid has high flow. Set it up so that both solenoids are on when more heat is required, than when the temperature is satisfied, turn off the high flow solenoid. When the temperature drops too much, kick the high flow solenoid back on. Probably a bit more complicated than what you are looking for, but it probably would keep temperature quit well.

 

Also, I'll just throw this out there. Use a raspberry pie to control the solenoids. Connect it to you network, set up a webserver on the pie, make a web page that can control the solenoids and display your temperature, and set up your router or an internal dns to point bbq.com to the pie so that you can control your bbq anywhere in you house by simply going to bbq.com. :)

[G+_Jason Perry]

610bob, my end goal is to have it controlled by an arduino. I think a pi is overkill.

 

I do however want it to both post and subscribe to an MQTT broker running on either a VM or a Pi over a ZigBee network. This should leave the greatest amount of flexibility for control and allow me to build in redundancy.

 

Well so much for the pi being overkill :)

[G+_Jason Perry]

Wayne Hobbins, I think everyones end goal should be to cook with charcoal. I am just looking to learn with my current cheap grill before it bites the dust and I get something better, something that I also need to control the air flow.

 

Do you have one of those temperature probes? It looks ideal for my needs. My only thought is if I can easily take it apart and mount the metal part on the inside of the box through a hole and mount the plastic part on the outside.

[G+_Jason Perry]

Wayne Hobbins, to answer your first question. My first goal is just to monitor the temp. After I am satisfied with that I think my next goal is to control air flow manually and insulate the box. If I make it to there my goal becomes automating the valves and airflow.

[G+_Jason Perry]

Eddie Foy, I think you hit the nail on the head for temp control.

 

My biggest thing is I want to seal up my box and control the air going in and out. I would like to play with a blower as well as more controllable venting first.

 

It would be nice to control the flame as well but the rigors in testing a home made system make me feel that is last.

[G+_Eddie Foy]

Keep it simple.  Reminds me of the space program in the 1960's.  The US/NASA spent about $175K developing the 'space pen' that can write in zero gravity and upside down.

 

 

The Russians said "Vee Joost Uze pinsel."

[G+_Ben Reese]

Yeah, but think of all the Facebook posts we can now make lying in bed thanks to that pen.

[G+_Jason Perry]

Wayne Hobbins Unless your my mother in law; then, put it on there for 9 minutes, flip it, leave for 8, sigh, and take it off