Temperature recorder

[Daniel G]

Not exactly related to RC, but....
I need to measure the temperature changes in an oven over about 3 hours.
I do have a Basic stamp and was figuring that I could use it to record the temperature outputs of a thermometer and send it back to the computer.
However, I don't quite know what I need to get in terms of a thermometer that will interface with a basic stamp. All the possible leads I have found were instantly outlawed, as they could only record 230 degree temperature.
Could someone give me some tips on a thermometer that would be able to handle >400 degrees fahrenheit?

[ALtitudeap]

ask this on teh Parallax forum

[vintage1]

No electronics will survive that temperature.
You need a sensor and some high temperature wire.

Probably a thermocouple?

google high temperature sensors and see what pops up.

[zs6smi]

You get sensors that you install inside oven to a converter that measure the temp inside look under thermocouples there are basically 2 types OHMS resistance or different metals giving out millivolts.

[Chippie]

You get sensors that you install inside oven to a converter that measure the temp inside look under thermocouples there are basically 2 types OHMS resistance or different metals giving out millivolts.


Ahhh back to my tiffying days.... ;)

The Ohms type referred to is commonly called an RTD and has a standard resistance of 100Ohms at 0 Celsius for a PT100 type.Usually connected to a Wheatstone Bridge suitably calibrated...

The thermocouple comes in different varieties made up from a pair of dissimilar metals that when heated generate an electric current(Its called the Seebeck effect....).You can make your own by taking a length of Copper wire and add a length of Constantan wire, twist two ends together and silver solder, connect the two free ends up to a millivoltmeter....the meter rises as the temp goes up...you will need a conversion table to go from mv to degreesC

If you make up your own t/c make sure you use the appropriate connecting cable to match or else you will end up with cold junction errors...

Have a look here for more info on temp measurement.....http://www.tc.co.uk/

[pbunn]

Ebay is loaded with thermocouples and RTDs. You can probably pick up a thermocouple for $10 or so. You need a thermocouple amp - google for many examples.

[Daniel G]

Ok, so I need a thermocouple....
I looked around in our garage and found what may be a thermocouple amp.
It has "thermocouple to milivolt converter" on it.
I'll see if I can get some pictures of it.

[Daniel G]

ask this on teh Parallax forum
I didn't know they had one...
I'll have to check it out. :)