Accuracy and uncertainty

Andrew · Post by **Andrew** » Mon Jan 29, 2007 10:34 am

Considering..
PT100 Sensor,Accuracy +/- 0.03 at 0Â°C (1/10th Class B)
PT104 Data logger, Accuracy@25Â°C 0.01Â°C

1. For your PT100 sensor is it +/-0.03% or +/-0.03Â°C at 0Â°C

2. Is there a technical reason why you quote accuracy at different temperatures for your devices? I am trying to come to an uncertainty value for the combined devices, do you have accuracy figure for the PT104 at 0Â°C? (or better still can you provide a combined figure for the sensor and the PT104)

3. For PT104 you quote 0.01Â°C is this +/-0.01Â°C @25 degrees

Thanks in advance
Andrew

ziko · Post by **ziko** » Wed Feb 07, 2007 10:32 am

Hi and thank you for your post.

This can be a little confusing to start off with, what you have to take into account is that the PT104 is in most part not in the same place as the sensors themselves. So the PT104s quoted accuracy is when it is at a temperature of 25 degC and not the PT100 sensor

So if your PT100 sensor is in a room at 0degC (but the PT104 is in a room at 25degC) your combined accuracy will be 0.01degC (for the PT104) and +/-0.03degC (for 1/10th din sensor).

To find out more information about how to calculate the accuracy for the PT100 sensors at different temperatures have a look at the following link:

http://www.lanzo.se/applications/pt100.html

Hope this helps.

Kind regards

Ziko