how could i measure thermocouple type K's voltage using arduino?

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1

Hi, umm excuse me

i try to measure the thermocouple type K's voltage using op-amp, but it seems like it doesn't measure the right voltage according to the temperature.

So i need to measure it from arduino uno and i dont know how to do that.
Could someone kindly explain to me how to program it so i could show it using a serial monitor?

btw, currently i am using Max6675 modul to convert the voltage to temperature reading.

Thank you so much before

2

With Arduino, a thermocouple amplifier of the proper type is required.

3

Hi,

Some How-to on temperature measurement HERE

And thermocouple-specific, diagram, code HERE

4

jremington:
With Arduino, a thermocouple amplifier of the proper type is required.

i am currently using max6675. i mean how could i measure the ADC voltage from thermocouple to the chip using arduino? i need this voltage to compare the voltage with the temperature reading

thanks before

5

terryking228:
Hi,

Some How-to on temperature measurement HERE

And thermocouple-specific, diagram, code HERE

yes sir, i am currently using max6675. i mean how could i measure the ADC voltage from thermocouple to chip using arduino? i need this voltage to compare with the temperature reading

thanks before

6

The output from a thermocouple is very small, in the low milliVolt range (< 1 mV) at room temperature, also your meter probes will cause an error that may be larger then the TC output, depending on room temp.

7

how could i measure the ADC voltage from thermocouple to chip using arduino?

You measure the output voltage of the thermocouple amplifier using the analogRead() command.

You will need to calibrate the value to compute the actual voltage or the temperature, by comparing to the reading obtained using a good quality multimeter or thermometer.

Calibration tutorial here.

8

You may have good reason for using a thermocouple, but reading the first line of reply #2 is a really good idea.

9

outsider:
The output from a thermocouple is very small, in the low milliVolt range (< 1 mV) at room temperature, also your meter probes will cause an error that may be larger then the TC output, depending on room temp.
Omega Engineering | Sensing, Monitoring and Control Solutions

yes i already have that conversion. so when i use a voltmeter it can't read the voltage and i tried using op-amp but it seems the result is not the same as the conversion before. i also already measured the voltage using arduino but the range in volt so it can't quite measured the voltage like i want in mV.

could you please tell me how to measure it using arduino in mV?

thanks before

10

jremington:
You measure the output voltage of the thermocouple amplifier using the analogRead() command.

You will need to calibrate the value to compute the actual voltage or the temperature, by comparing to the reading obtained using a good quality multimeter or thermometer.

Calibration tutorial here.

wow thank you sir. so i already measured the voltage using arduino with the analogRead() command and it is in V. could you tell me how to measured it in mV?

thank you in advance

11

Nick_Pyner:
You may have good reason for using a thermocouple, but reading the first line of reply #2 is a really good idea.

thank you for the answer :slight_smile:

12

could you tell me how to measured it in mV?

To get mV from V, multiply by 1000.