Temperature measurement using PT100
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The Resistance Temperature Detector (RTD) is a temperature sensing device whose resistance changes with temperature, typically built from platinum. To measure the resistance across an RTD, apply a constant current, measure the resulting voltage, and determine the RTD resistance. The PT100 is a popular RTD with a resistance of :math:`100 \Omega` at 0°C.  Resistance of a PT100 element is related to the temperature
by the equation :math:`R(T) = R_0 (1 + AT + BT^2)`, where
:math:`A = 3,9083 \times 10^{−3}` and :math:`B =  − 5,775 \times 10^{−7}`.

Objective
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Record the temperature of a liquid by using a Pt100.

Procedure
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.. image:: schematics/pt100.svg
	   :width: 300px

-  Make the connections as shown in the figure.
-  Enter the Gain, Offset error and the Current from CCS
-  Select the temperature range and time intervals
-  Select the required parameters and press START


Cooling curve of water is shown in the figure below.

.. image:: pics/pt100-screen.png
	   :width: 300px

Discussion
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The accuracy of the measurements can be increased by the following steps.

Measure the actual current from CCS and enter it in the GUI, it could be slightly
different from 1.1mA. The input to A3 is amplified 11 times by
connecting :math:`1~k\Omega` resistor from Rg to Ground.  The gain and offset should
be measured an entered in to the program.
