The difference between armored thermocouple and armored thermal resistor

The basic principle of temperature measurement with armored thermocouples is that two homogeneous conductors of different components form a closed loop. When there is a temperature gradient at both ends, current will flow through the loop. At this time, there is a Seebeck electromotive force - thermoelectric electromotive force between the two ends, which is the so-called Seebeck effect.
The two homogeneous conductors of different components are thermocouples. The end with higher temperature is the working end, and the end with lower temperature is the free end. The free end is usually at a constant temperature.
According to the functional relationship between thermoelectric electromotive force and temperature, a thermocouple scale is made; the scale is obtained when the temperature of the free end is 0℃, and different thermocouples have different scales.
When a third metal material is connected to the armored thermocouple loop, as long as the temperature of the two contacts of the material is the same, the thermoelectric potential generated by the thermocouple will remain unchanged, that is, it will not be affected by the third metal connected to the loop.
Therefore, when measuring temperature, the armored thermocouple can be connected to a measuring instrument. After measuring the thermoelectric electromotive force, the temperature of the measured medium can be known.
Armored thermal resistors measure temperature by using the characteristic that the resistance of a material changes as the temperature changes. When the resistance value changes, the working instrument displays the temperature value corresponding to the resistance value. Armored thermal resistors are a type of temperature sensor. They are smaller in diameter than assembled thermal resistors, easier to bend, and have good shock resistance. They are suitable for installation in places where assembled thermal resistors cannot be installed. The WZPK series armored thermal resistors use imported thermal resistor temperature measuring elements. Therefore, they have the advantages of accuracy, sensitivity, fast thermal response time, stable quality, and long service life.
The outer protective sheath of the armored thermal resistor is made of stainless steel and filled with high-density oxide insulators. Therefore, the armored thermal resistor has strong anti-pollution performance and mechanical strength, and is suitable for installation in harsh environments. The outer protective tube of the armored thermal resistor is made of stainless steel and filled with high-density metallurgical grade magnesia oxide insulators. Therefore, it has strong anti-pollution performance and excellent mechanical strength, and is suitable for installation in harsh environments. Armored thermal resistors are usually composed of armored platinum thermal resistor temperature sensing elements, mounting fixtures, wiring devices and other main components. They have short thermal response time and reduced dynamic error; they have small diameter and limited length.