RTD stand for :-
R-Resistance
T-Temperature
D-Detector
RTD also known as Resistance Thermometer.
RTD is a temperature sensor used to measure the Temperature of any industrial
process.
Working Principle:
RTD works on principle that the
electrical resistance of a metal changes with change in Temperature. Whenever temperature of a metal increase, the it’s resistance also increase.
RTD element is made of restive material most likely Platinum.
When ever the temperature of a measuring element is changes its resistance will also increases linearly. The resistance change in RTD Element is directly propositional to the change in temperature of RTD element. Why Platinum is used in RTD Elements
Platinum, Nickel or Copper may used in RTD element but he
Platinum is the most commonly used material because
Platinum has high accuracy, excellent repeatability and also
it is linear over a wide range of temperature. These
properties makes the Platinum best suitable material.
Most importantly the Platinum has large enough Resistance
Temperature coefficient of Resistance α (Alpha). Which mean more change in resistance with per degree change in Temperature.
There are three types of RTD available in Platinum Sensing Meterial
- PT-100 : RTD Output will be 100 Ohms on 0 °C .
- PT-500 : RTD Output will be 100 Ohms on 0 °C
- PT-1000 : RTD Output will be 100 Ohms on 0 °C
