Temperature sensor technology

The main difference between an RTD and a Pt100 is the material used for the sensing element: PT100 is a specific type of RTD thermal resistor, and its name comes from “Platinum” (platinum) and “100” (100 ohms at 0°C). It is the most commonly used RTD sensor and is widely used in industrial process control, laboratory measurement and other fields that require high-precision temperature monitoring. The advantages of PT100 include:

The thermal resistance formula is in the form of Rt=Ro(1+A*t+B*t*t);Rt=Ro[1+A*t+B*t*t+C(t-100)*t*t*t], t represents Celsius temperature, Ro is the resistance value at zero degrees Celsius, A, B, C are all specified coefficients, for Pt100, Ro is equal to 100℃.

A PT100 sensor acquires temperature by measuring the change in its electrical resistance, which directly correlates to the temperature it is exposed to; as the temperature increases, the resistance of the platinum element within the sensor also increases, allowing for a precise calculation of the temperature based on this resistance change; essentially, the “100” in PT100 signifies that the sensor has a resistance of 100 ohms at 0°C, and this value changes predictably with temperature fluctuations.

Platinum resistors are widely used in the medium temperature range (-200～650℃). At present, there are standard temperature measuring thermal resistors made of metal platinum on the market, such as Pt100, Pt500, Pt1000, etc.

The temperature measurement range of the commonly used platinum resistance Pt100 sensor probes is -200～850℃, and the temperature measurement ranges of Pt500, Pt1000 sensor probes, etc. are successively reduced. Pt1000, temperature measurement range is -200～420℃. According to the IEC751 international standard, the temperature characteristics of the platinum resistor Pt1000 meet the following requirements: