thermo couple

[januar1983]

pls help me how to use thermocouple for measure the temperatur

 

[Sceadwian]

https://en.wikipedia.org/wiki/Thermocouple

 

[januar1983]

thanks, i want to know how i interface the thermo couple to microcontroller, i use avr for microcontroller

 

[SPDCHK]

Thermocouples (CT) generate a very low voltage (typically few mV/°C). You will need to amplify the input mV signal from the CT into a OP-Amp to get a more usable voltage for the microcontroller input, typically 0-5V.

TC's also tend to be used over a wide range of temperatures, eg. 0-1500°C. If you are only going to use it for a low range measurement, rather use something like a PT100, (RTD)

Also, if it has to be a TC, you must compensate for cold junctions.

 

[eblc1388]

Thermocouples (CT) generate a very low voltage (typically few mV/°C).

Which types of thermocouple give such a big output of several mV per degree C?

 

[januar1983]

i have read the article and all the thermo couple it has generate only milivolt

 

[keithK]

Yes. Thermocouples have low millivolt output. Look at the AD597 from Analog Devices. **broken link removed**.
That will give you a good idea of what is needed to interface a thermocouple. Type K is the most common.
Check Omega.com for some great info on temperature sensing.

 

[januar1983]

thanks for all i got the analog device to interface with the thermo couple