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Special meters: Temperature | Distance | Data loggers => Temperature Thermocouple (Sensor) K Type, Pt100, Pt1000 => Topic started by: Kiriakos GR on May 06, 2019, 10:24:26 AM

Title: Reference values according to EN 60 751 (ITS 90) for Pt100 temperature sensors
Post by: Kiriakos GR on May 06, 2019, 10:24:26 AM
This journey started by me exploring Precision Industrial RTD Probes ... Resistance Temperature Detector (RTD)

I did find brief information’s relative to Platinum Resistance RTD and I am now even aware of a manufacturing challenge when such probes operate at above 400C as their new enemy this is oxidation at Platinum element surface.

This new Blog topic it is not aiming to be some sort of RTD probe engineering analysis, but to rather help any newcomer whom wishes to explore measuring range and ohm values of Pt100 RTD.

It is not the first time when scientific community this making charts and most explanations needed for newcomers these they are missing.

Very recently I got my own precision benchtop multimeter this has temperature measurement only by the use of RTD 385 / Pt100 probe (100 Ohm).
6 ½ digits resolution for temperature measurement this looks as extraordinary in my eyes, when vast majority of handheld multimeter with a K type thermocouple they deliver three digits resolution.
 
Because of such high resolution at six digits, my next though was of me finding Pt100 temperature sensors chart in 1°C steps.

I did find many but I could not understand How-to about regarding (translating) such 1°C steps.
Originally I was able to understand only the relation of Temperature and Ohms at round numbers 10, 50, 100, 400 Celsius.
After receiving a bit of help from the Holy Spirit I did realize that horizontal chart this is 1C steps.

Now from 0C and in to the positive curve, resistance value (in steps) this increases, and at 0C and negative curve (- 200) resistance value (in steps) this decreases.
 
Today I have understanding that it was quite normal for me about getting that much confused (as newcomer visitor at the RTD world).

Such conversion table (Resistance / Celsius) this is work of someone else, and no one can be familiar with that in just of few minutes of time.
 
Bellow they are pictures from Pt100 compete chart, which my recommendation to you this is to download and print them for your reference.  :)
Title: Re: Reference values according to EN 60 751 (ITS 90) for Pt100 temperature sensors
Post by: Kiriakos GR on June 02, 2019, 03:35:54 PM
From time to time I do some thoughts about making my own PT100 simulator.  :)
Still I am undecided.

Even so I do collect ideas scattered worldwide regarding quantity of testing values.
Below it is a good example regarding measuring (testing range).