PT100 and PT1000 are the most common type of Resistance Temperature Detector (RTD). RTDs have character that their resistance value(Ω) is linear relation with temperature(℃) change.

Temperature transmitter converts the resistance signal (Ω) from a RTD into a more robust 4~20 mA or digital signal for interfacing into other control equipment.

To ensure accuracy a temperature transmitter is capable of isolating, amplifying, linearizing and filtering noise from the temperature sensor signal.