Thermocouple

[mfiore]

I know this comes up periodically, but equipment changes, as do ideas. So I thought I'd return to this topic.

During my dome build, I embedded 3 thermocouples at various places (floor, dome, etc). Now that I'm enclosing the dome (walled enclosure), I am not sure what do do with the three wires. I have a IR gun that I can plug them into individually, but wouldn't mind a more permanent mount. Can anyone recommend a TC reader that I can mount in the enclosure wall that could read the three probes (perhaps a switch between them?) that won't cost a fortune. I know, a lot to ask, but I'm curious what others are doing. I'm not sure I want to have three wires poking out of the wall, and continuously plugging in the IR gun to make a reading.

Thanks

[mfiore]

Re: Thermocouple

I posted this at a time of low usage. Thought I'd try again. Any suggestions?

[dmun]

Re: Thermocouple

This is unrelated to the current question, but a promising, affordable, insulation board, Foamglas, has come up in another thread.
http://www.fornobravo.com/forum/f8/d...arth-6970.html
It's rated for 900 degrees fahrenheit, which is quite a bit less than the boards we use now.
My question for the thermocouple mavens is this: how hot is the bottom of the firebricks on the oven floor likely to get at full pizza heat?

[nitro69]

Re: Thermocouple

Mike,

Take a look at Auber Instruments - auberins.com, Temperature control solutions for home and industry

[Lars]

Re: Thermocouple

Hi MFiori,
I was thinking about putting in thermocouples, but I really don't know exactly what I need to do put them in.

One thing I read that just leaving a straw would allow you to insert something later..

What exactly are you calling a thermocouple? Is it just a thermally conductive wire ( like copper?) embedded in there, or something more expensive?

I would be very interested in the temperatures at various depths of the insulation, thermal mass, etc.

Lars.

[mfiore]

Re: Thermocouple

Lars, I'm certain someone with more a more sophisticated knowledge of engineering will pipe in, but in general, the thermocouples are a probe with two different metals are used. They generate different low voltages in response to temperatures. The voltage differential then relates to a specific temperature.

They are available from many online sources. I got mine from Omega Engineering. Looks something like this


You can stick the end anywhere you want to monitor temps. Many builders stick one in the floor hearth, one in the dome, etc. These, however, are just probes. They are of no value without a reader to display temps as a meaningful number. The reader is what I am looking for.

If I were to rebuild my oven, I'm not sure I would use a thermocouple. The cost is not insignificant. I have a feeling it is something that I will use initially to learn more about my oven's behavior, then forget about over the years.

[blacknoir]

Re: Thermocouple

or try this: Thermok: 4 Channel Thermocouple Display - APRS World, LLC

[mfiore]

Re: Thermocouple

Thanks, Shay

Apparently that model has been discontinued.

A big problem I am having is that I do not have electricity at my WFO site. The reader needs to be battery powered.

[Lars]

Re: Thermocouple

Mike,
No electricity? Sounds like me. How did you build? ( generator?)

Lars.

[mfiore]

Re: Thermocouple

Sorry, I should clarify before I make myself sound too heroic.

I do have electricity near the oven, and used many power tools in it's making. I don't, however, have a power source imbedded in the oven enclosure (some ovens have electric lights, etc) that I could use to plug in a permanently mounted thermocouple reader.

[dbhansen]

Re: Thermocouple

Mike, I called Omega a while back on this and they don't seem to offer any great options. They have some low-voltage "panel meters" that take multiple thermocouple inputs, but you'd have to figure out how to wire them to a battery. The products they mentioned are the DP462 and DP1096-KF. I'm electrically challenged, so that's beyond my capabilities. There must be other options out there!

Daren

[nitro69]

Re: Thermocouple

You could try looking at McMaster Carr website. They have alot of items with some good prices.

[blacknoir]

Re: Thermocouple

They still might have some of those discontinued models for sale though, but you have no power so Battery Powered : http://us.fluke.com/usen/products/Fluke+50.htm