Measure a resistance of a temperature sensor (PT100)

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1

hi,
i want to measure the resistance of the sensor (PT100) any idea how to do that?

thanks in advance

Felix

2

Are you trying to interface a specific PT100 sensor to a Pi?

3

One way to do it is use this

4

And this code may be adaptable to the board.

5

okay, thx for all ideas. it looks like that it is not possible only with the automation hat (sorry i forgot to explain what i had to work with)

6

The PT100 is a 3 wire sensor. You might have better luck with a 2 wire sensor, although it will be slightly less accurate. What is your intended purpose?

7

I read about the PT100 that it is possible to use the 3 wires also like a two wire system if you put both wire to one connector. the second/third wire is only to measure the wire resistance to calculate a better result.
Anyhow, how i can i use a two wire PT100 with the automation hat ?

my use case is actually just for playing around with the automation hat and my PT100 sensor. maybe i want to measure the temp of the heating of my house or the hot water tank ??? The ideas are growing with the solutions ;)

8

If memory serves, the 3 wire thermistors use two elements with slightly different curves for more accuracy. If you short one of the wires to the common you may be able to just measure the other sensor.

Yes, all these little sensors have so many uses. I have an Enviro+ set up with a Pi Zero as a small weather display in my home. I “discovered” the Breakout Garden Mini as a wonderful way to play with them. I can swap them in and out as needed.