What is the difference between armored thermal resistor and thermal resistor temperature sensor?

Although armored thermal resistors are widely used in industry, their application is limited by their temperature measurement range. The temperature measurement principle of thermal resistors is based on the characteristic that the resistance value of a conductor or semiconductor changes with temperature. It has many advantages, such as remote transmission of electrical signals, high sensitivity, strong stability, good interchangeability and accuracy, but it requires power excitation and cannot measure temperature changes instantaneously. Industrial thermal resistors generally use Pt100, Pt10, Cu50, Cu100, and the temperature measurement range of platinum thermal resistors is generally minus 200-800℃, and that of copper thermal resistors is minus 40 to 140℃. Thermal resistors are classified into the same types as thermocouples, but they do not require compensation wires and are cheaper than thermocouples.

Thermal resistor temperature sensors are sensor thermometers that use the principle that the resistance value of a conductor or semiconductor changes with temperature to measure temperature. What is the difference between armored thermal resistors and thermal resistor temperature sensors?

Thermal resistor temperature sensors are divided into two categories: metal thermal resistors and semiconductor thermistors. Thermal resistors are widely used to measure temperatures in the range of -200~+850°C. In a few cases, the lower temperature can be measured to 1K and the higher temperature can reach 1000°C.

From the temperature measurement principle of thermal resistors, it can be seen that the change of the measured temperature is directly measured by the change of the resistance value of the thermal resistor. Therefore, the change of the resistance of various wires such as the lead wire of the thermal resistor will affect the temperature measurement.

The armored thermal resistor is a solid body composed of a temperature sensing element (resistor), lead wire, insulating material, and stainless steel casing. Its outer diameter is generally φ2-φ8mm, and the smallest can reach φ0.25mm. Compared with ordinary thermal resistors, it has the following advantages:

① Small size, no air gap inside, thermal inertia, and small measurement value;

② Good mechanical properties, vibration resistance, and impact resistance;

③ Can be bent for easy installation;

④ Long service life.

Armored thermal resistor is a commonly used temperature measuring element in temperature measuring instruments. When the two ends of two conductors of different components are connected into a loop, when the temperatures of the two junction thermocouples are different, a thermal current will be generated in the loop. If there is a temperature difference between the working end and the reference end of the thermocouple, the display instrument will indicate the temperature value corresponding to the thermoelectric potential generated by the thermocouple.

Armored thermal resistor is a temperature sensor. It has a smaller diameter than assembled thermocouples, is easy to bend, has good shock resistance, and is suitable for installation in places where assembled thermocouples cannot be installed. The armored thermocouples produced by the company use imported thermal resistor temperature measuring elements. Therefore, it has the advantages of accuracy, sensitivity, fast thermal response time, stable quality, and long service life.