RTD means of the detector the temperature of the resistance. RTD sort of variable resistance sensitive to temperature, which means temperature variations, etc. change. In fact, by measuring its resistance, etc. can be average, it determined. For this reason, this tool as a temperature sensor are used.

change the resistance of the thermistor circuit, the bridge accuracy measure.

the difference, RTD, and thermistor:
the thermistor, usually from the material, semi-conductive have been formed. RTD from metals or metal alloys are made.
domain feel RTD more from the thermistor.
changes resistance in proportion to temperature in a thermistor for non-linear and in RTD almost linear.
changes the resistance of the thermistor, much more than RTD.
the advantage of the above caused in the industries of precision instruments, advanced (like the PLC) more from the thermistor are used, but due to non-linearity, etc. in circuits, electronics, analog more of RTD used.

the most common type of RTD, the name of the PT100. PT100 explainer platinum as the sensor element and the resistance of 100 .. game, play online at zero degrees Celsius.

in the form of wire wrapping, basic PT100 shown that for distances of a few meters amounts accurate data transfer.

but if the measurement is too accurate, need not, or distance, it can be some wire in the integration of ... and circuits, three wire and two wire to work'.