Hello all,

I have maybe a stupid qeustion but i will asking anyhow :
Is it possible that a analog amplifier (4-20 mA/24 V DC) connected on a 3 or 4 wire PT100 will behave not linear while the PT100 (measuring range 0-150 C°)is good functioning ?
I want to know if calibrating at 3 points (0-75-150 C°) is neccerary when calibrating at one point is enough when you check the whole loop.
The PT100 is always linear but i want to calibrate with amplifier and i am curious if the amplifier is acting always linear between 4-20 mA when i calibrate.
I see a amplifier only as a simple converter from resistance to mA ?

Thanks in advance for the answer.

Rollo

 

Welcome.

Care to explain a bit more ?

 

Hello,

PT100 sensor are not lineair.
There are even tables to translate the resistance to the temperature.
Here is a page from teh EDUCYPEDIA with circuits and other information on the PT100:
Pt100

Bertus

 

Welcome.

Care to explain a bit more ?

Hello Rif,
I have more info added on the first post and more info below:

When i determine a error of 1%,is this error then on the whole range when i connect de PT100 and the programmed amplifier ?
Is this what you looking for?