Solution for high temperature measurement

[seadolphine2000]

Hi,..

I want to measure a temp that is very high(not sure from the value but for sure it's over 150c ).

Any ideas.?????????

Thanks for considerations

P.S.: Please without microcontrollers, only discrete components(opamps, R, C,..).

Thanks

 

[simov]

High temp measurment

if you want to integrate the temp sensor in your chip, you can monitor high temp by means of measuring diode voltege

 

[flatulent]

Re: High temp measurment

There are standard type sensors for this such as bimetal ones and temperature variable resistance metals.

 

[IanP]

Re: High temp measurment

Have a look in this application note:
https://ww1.microchip.com/downloads/en/AppNotes/00684a.pdf
It describes temperature measurement using thermocouples. There are examples of interface amplifiers and instead of feeding this signal to ADC you can use a cheap LCD 3½ display with built-in volmeter or any other linear or digital display which can be scaled in °C.
Regards,
IanP

 

[attylus76]

Re: High temp measurment

Hi,
According to my opinion you would have to use a thermocouple of K type that é enough linear.

 

[Humungus]

Re: High temp measurment

Is the electronics also placed at high temperature??

What precision do need?

Must you give an analog or digital result?

Is it for a company or university?

 

[Kral]

Re: High temp measurment

An RTD (Resistance Temperature Detector) can handle the job nicely. It's a temperature sensitive resistor. It has an advantage over thermocouples in that it requires no cold junction compensation.
.
See, for example, the Heraeus SMD 0805 (V) at.
. h**p://www.dwmai.com/products/smd/SMD_0805_(V)_-e.pdf.

If you choose to use a thermocouple, there are specialized ICs that will do the cold junction compensation for you:
~ AD594 (For Type J thermocouple)
~ AD595 (For Type K thermocouple)
Otherwise, you must do the cold junction compensation yourself. See, for example, NSC LB 24:
h**p://www.national.com/ms/LB/LB-24.pdf

 

[seadolphine2000]

Re: High temp measurment

Hi,..

I'll go with the thermistor as it's the only sensor available for now. I'll use w104d to measure the unknown temp and put this thermistor in an inverting amp(opamp) thus the measured output voltage will be used to get the thermistor resistance.

Any idea how to implement something like this.?

Thanks

 

[WinterInJuly]

Re: High temp measurment

Thermistor is often used to measure the Temp below 600 0C, if you want to measure high Temp, you can use Thermocouple type J, type K...

 

[seadolphine2000]

Re: High temp measurment

Thanks for help,.. but the temp is about the 400 C. I got this value when we used a 100Kohm thermistor.

The question now is, Is this value reliable.???? Can I make the design according to this value.?????

Thanks for help and consideration.