RTDkäyrä

RTDkäyrä, meaning "RTD curve" in Finnish, refers to a graphical representation of temperature versus resistance for a Resistance Temperature Detector (RTD). An RTD is a type of temperature sensor that exhibits a change in electrical resistance with changing temperature. The RTDkäyrä illustrates this relationship, showing how the resistance of the RTD increases or decreases as the ambient temperature rises or falls.

Typically, RTDs are made from pure metals like platinum, nickel, or copper. Platinum is the most common due to its stability, linearity, and wide temperature range. For a platinum RTD, the resistance is approximately zero ohms at absolute zero, but in practical applications, it's measured at a reference temperature, often 0°C. The curve shows a generally linear progression of resistance with temperature over a significant range, though there can be slight non-linearities, especially at extreme temperatures.

The RTDkäyrä is crucial for accurately interpreting the resistance measurement from an RTD and converting it into a precise temperature reading. Manufacturers provide these curves, or mathematical equations that describe them, to allow users to calibrate and use their RTD sensors effectively. Understanding the RTDkäyrä ensures that the temperature data obtained is reliable for various industrial, scientific, and medical applications where precise temperature monitoring is essential. Different types of RTDs, such as PT100, PT1000, or others, will have distinct RTDkäyrä characteristics based on their material and base resistance.