Resistance Temperature Detectors
Resistance Temperature Detectors (RTD's) measure temperature, as they are among the most precise temperature sensors available with resolution and measurement uncertainties or ±0.1 ℃ or better possible in special designs.
An RTD capitalizes on the fact that the electrical resistance of a material changes as its temperature changes, relying on the resistance change in a metal. The relationship between an RTD's resistance and the surrounding temperature is highly predictable,
allowing for accurate and consistent temperature measurement. By supplying an RTD with a constant current and measuring the resulting voltage drop across the resistor, the RTD's resistance can be calculated, and the temperature can be determined.