A Pt100 RTD sensor is one of the most common types of temperature sensor on the market today. It is an example of a resistance temperature detector – or RTD temperature sensor - which are temperature sensors that contain a resistor element that changes resistance value as it is exposed to temperature changes.
A bit of historyPt100 sensors have been used for many years to measure temperature in laboratory and industrial processes, and have developed a reputation for accuracy, repeatability, stability, and a wide temperature range.
A Pt100 sensor is named as such because these sensors are Platinum-based: ‘Pt’ being the chemical symbol for Platinum. Although expensive, Platinum provides both greater linearity and greater stability than other materials. The 100 indicates that the temperature sensor’s resistance at 0 oC is 100(omega).
In a typical Pt100 RTD, the platinum wire is wrapped around a ceramic core or wound into a coil. The ceramic core helps to provide stability in extreme temperatures and provides good thermal insulation from changes in ambient temperatures. In addition, the ceramic core helps protect the delicate platinum wire from damage.
How Do Pt100 Sensors Work?Pt100 temperature sensors utilize the principles of electrical resistance to measure temperature, which state that a metal’s resistance to the flow of electricity increases as the temperature that metal is subjected to increases. This change in resistance as the temperature changes is predictable, and it is this predictable change that is used to determine temperature.
The Pt100, which is a Platinum resistance thermometer, is one of the most accurate temperature sensors and is capable of providing excellent stability and repeatability. These sensors are also relatively immune to electrical noise and therefore well suited for temperature measurement in industrial environments, especially around motors, generators, and other high voltage equipment.