Kipp&Zonen CNR 4 Net Radiometers - Manual (Page 27)

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2.5 Properties of the Pt-100 and thermistor
The Pt-100 is a common temperature sensor. Essentially it is a resistor that is temperature dependent. The Pt-100
complies with the specifications of DIN, class A. A table stating the resistance values can be found in chapter
1.1.6.3
Alternatively the thermistor, (nominal value is 10k Ohms at 25 degrees Celsius) can be used. A table stating the
resistance values can be found in table 1.1 The thermistor has a much larger resistance value than the Pt-100, also
the change in resistance with respect to temperature, in absolute terms, is greater. Therefore the cable resistance
can be neglected, and only a 2-wire connection is used for the thermistor measurement, contrary to the 4-wire
connection of the Pt-100.
The accuracy of both temperature sensors is equal and the selection to use one or the other mainly depends on the
possibilities of the connected data logger or data acquisition system.