This is for a competitive bar b que pit. I need a device to serve as a temperature limit. The ideal device would use a plug-in type K thermocouple in a needle probe. The device would have a 125 vac relay capable of 15 amps. The device plugs into the wall, a heating element plugs into the device. The tcouple goes into the meat. The normal state is the relay is closed. This could be initiated with a push button. The heating element stays energized until the meat temperature reaches a variable set point between 140 and 180 degrees F. At the set point the relay opens and stays open until the device is reset with the push button. The reset should not work unless the couple probe is below the set point.
so, does anyone know of a device already made with this capability? Even a simple circuit design would do for me. (I am a retired Clanky engineer type, not a Sparky type.)
I might go with an Arduino or ? but would need serious retraining. My first inclination was for a pneumatic device!

 

There are temperature controllers available that should be able to do most of what you want.

 

But these ...

But these all seem to have wires that when the meat turns on the spit will wind around and around. I would like one that is wireless or a rotisserie that rotates 360 degrees in one direction, then reverses and goes 360 in the reverse so the cord does not wrap around the spit.

You seems to be asking a different question. Maybe post it in a new thread. Two solutions come to mind: 1) put the TC amplifier on the rotating part and transmit wirelessly; or 2) Do the same as in #1 , but use slip rings. So far as I know, thermocouples do not work well with slip rings.

 

I am seeing two different post:

This is for a competitive bar b que pit. I need a device to serve as a temperature limit. The ideal device would use a plug-in type K thermocouple in a needle probe. The device would have a 125 vac relay capable of 15 amps. The device plugs into the wall, a heating element plugs into the device. The tcouple goes into the meat. The normal state is the relay is closed. This could be initiated with a push button. The heating element stays energized until the meat temperature reaches a variable set point between 140 and 180 degrees F. At the set point the relay opens and stays open until the device is reset with the push button. The reset should not work unless the couple probe is below the set point.
so, does anyone know of a device already made with this capability? Even a simple circuit design would do for me. (I am a retired Clanky engineer type, not a Sparky type.)
I might go with an Arduino or ? but would need serious retraining. My first inclination was for a pneumatic device!

Then another poster adds a rotating spit:

But these all seem to have wires that when the meat turns on the spit will wind around and around. I would like one that is wireless or a rotisserie that rotates 360 degrees in one direction, then reverses and goes 360 in the reverse so the cord does not wrap around the spit.

The reality is you can have anything you want as long as you are willing to pay for it. I have seen rotary slip ring arrangements for thermocouples but have no idea how well they do or do not work. You can rotate a spit and reverse using limit switches. Anything like this would be outside the temperature zone like on or around the spit motor. As to the thermocouple? Type K maybe 6" to 8" length in a 1/8th sheath diameter and sheath material stainless steel with several feet of stainless steel sheath extension wire. The armored type over braid stuff. There are controllers which will do just about anything you want with multiple outputs reverse or forward acting.

The idea starts with defining in detail and that means in detail, detail what is wanted starting with the sensor. Years ago I roasted several whole hogs (about 130 lbs dressed) and all we ever used was an off the shelf meat thermometer shoved into a hind quarter. You know when you are close and where you want to be. I guess the process could be automated to an extent. When I think thermocouples I see large pieces of meat like a whole hog or steer which the internal temperature changes slowly with when cooking. Using electric elements the heating process could actually be done with a PID loop controller, with coals we just backed off the number of coals when we were close. Actually coals and wood.

Ron

 

I am seeing two different post:


Then another poster adds a rotating spit:


The reality is you can have anything you want as long as you are willing to pay for it. I have seen rotary slip ring arrangements for thermocouples but have no idea how well they do or do not work. You can rotate a spit and reverse using limit switches. Anything like this would be outside the temperature zone like on or around the spit motor. As to the thermocouple? Type K maybe 6" to 8" length in a 1/8th sheath diameter and sheath material stainless steel with several feet of stainless steel sheath extension wire. The armored type over braid stuff. There are controllers which will do just about anything you want with multiple outputs reverse or forward acting.

The idea starts with defining in detail and that means in detail, detail what is wanted starting with the sensor. Years ago I roasted several whole hogs (about 130 lbs dressed) and all we ever used was an off the shelf meat thermometer shoved into a hind quarter. You know when you are close and where you want to be. I guess the process could be automated to an extent. When I think thermocouples I see large pieces of meat like a whole hog or steer which the internal temperature changes slowly with when cooking. Using electric elements the heating process could actually be done with a PID loop controller, with coals we just backed off the number of coals when we were close. Actually coals and wood.

Ron

Look at post #1! "This is a competitive BBQ Pit. I am not familiar with BBQ competition, and I would try to avoid anything cooked in such a competition. If the TS really wants such a system they can have it custom made by a company local here, Dave Ray Associates. Given the description they can deliver.

 

hi,
Created a new Thread here, to cover the change in the original Topic.
https://forum.allaboutcircuits.com/threads/temperature-devices.169960/post-1514127

Please stay on Topic.

Mod.

 

Excellent already readymade device from SESTOS cost about 20 USD. It is impossible to make ANY better artwork even for 100x of this expense. Accuracy 0,1C all thermocouples supported, inside the adaptive PID, relay output, digitally programmable, five digit readouts etc etc. I love it because of price / quality ratio. www.sestos-hk.com Exists online ordering system via postal parcel

 

hi,
Created a new Thread here, to cover the change in the original Topic.
https://forum.allaboutcircuits.com/threads/temperature-devices.169960/post-1514127

Please stay on Topic.

Mod.

Thank you Eric as usual.

Ron

 

Excellent already readymade device from SESTOS cost about 20 USD. It is impossible to make ANY better artwork even for 100x of this expense. Accuracy 0,1C all thermocouples supported, inside the adaptive PID, relay output, digitally programmable, five digit readouts etc etc. I love it because of price / quality ratio. www.sestos-hk.com Exists online ordering system via postal parcel

Could you show a link, Janis?

 

Look at post #1! "This is a competitive BBQ Pit. I am not familiar with BBQ competition, and I would try to avoid anything cooked in such a competition. If the TS really wants such a system they can have it custom made by a company local here, Dave Ray Associates. Given the description they can deliver.

I did and tried to address both. That said BBQ Competitions are really cool. Every year we have a few Rib Burn Off competitions in our area. Great stuff, really great assorted BBQ from hog to chicken to anything else on a grill. These are people who take their BBQ seriously including making your own sauce. Sometime try and catch an episode of BBQ Pit Masters on TV.

Anyway as pointed out there is no shortage to programmable temperature controllers off the boat at very low prices. Just find one with the desired features and program it.

Ron

 

That said BBQ Competitions are really cool. Every year we have a few Rib Burn Off competitions in our area

Like him reading a whole thread before answering, he doesn't pay much attention to what is happening around him. https://www.google.com/search?clien...&ved=0ahUKEwjvnpuVzsfpAhWql3IEHWglDFYQ4dUDCAs