TC-08 Accuracy

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Raul

TC-08 Accuracy

Post by Raul » Fri Jul 02, 2010 2:21 am

Hi,
I would like to estimate the error of temp. measurements.
I am using a K-thermocouple with a +/- 2.2 °C error
The TC-08 datasheet says:
Temperature accuracy: Sum of ±0.2 % of reading and ±0.5 °C

1) is the percentage calculated from the absolute temperature (in K) or from the temperature difference between the thermocouple measurement and the cold junction (ambient temp)?

2) does this value include the thermocouple error? (I doubt it)

I thought to calculate the total error as follows:
for measuring T=300°C in a room at 25°C.

dT=sqrt( (0.2*(300-25)/100 + 0.5)^2 + 2.2^2 ) = +/- 2.4°C

is that correct?
Thank you,
Raul

PeterF
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Re: TC-08 Accuracy

Post by PeterF » Tue Jul 06, 2010 3:33 pm

Hi,
Yes, the cold junction (ambient) temperature is taken as the starting point for calculation of scaling errors, just as you have done in your equation. Thermocouple error is in addition to the TC-08 accuracy and from what I can remember your equation to calculate total error is correct.
Regards,
PeterF.

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