中文版 | English
Support
     Technical Support
     FAQ
     After Service
     Sales Network

Tel:86 755 27308212 / 27307702 / 27308249 / 27307589
Fax:86 755 27307986
Web:www.szkemin.com
E-mail:qiuyangqi@szkemin.com
Add:No.46,Mei Hua Road,East District,Baishixia,Fu Yong Town,Bao'an District,Shenzhen, Guangdong, China
Code:518103
Technical Support
The difference between the thermocouple and thermal resistance
Visit: Date:2013-11-29
Thermocouple and thermal resistance are the contact temperature measurement of temperature, although the same is measuring the temperature of the object, but the principle and characteristics of them are not the same.

First of all, introduce thermocouple, thermocouple temperature device is the most widely used in temperature measurement, the main features of the kiss is wide, the performance is stable, and has the advantages of simple structure, good dynamic response, more able to remote 4-20mA signal, which is convenient for automatic control and centralized control. Temperature measurement principle of the thermocouple is based on thermoelectric effect. Two different conductor or semiconductor connected to form a closed loop, when the two junction temperature is not at the same time, the loop will produce thermal potential, this phenomenon is called the thermoelectric effect, also known as the Seebeck effect. Thermoelectric generation in closed circuit potential has two potential; the potential temperature and contact potential. The potential temperature refers to both ends of the same conductor potential due to the temperature of different, different conductors with different electron density, so the potential they have is not the same, but the contact potential by definition refers to two different conductor in contact, because different electron density and their resulting in electron diffusion certain, potential formed when they reach a certain equilibrium, the contact potential depends on the size of the two kinds of different material properties of conductors and their contact point temperature. The application of thermocouples with a standard specification, the provisions of the thermocouple is divided into eight different indexing, respectively B, R, S, K, N, E, J and T, the measurement of the temperature minimum detectable minus 270 degrees Celsius, up to 1800 degrees Celsius, where B, R S series, belonging to the platinum thermocouple, the platinum belongs to the precious metal, so they were also called noble metal thermocouple and the remaining few called cheap metal thermocouple. The structure of the thermocouple has two kinds, common type and armored. Ordinary thermocouple in general by the hot electrode, insulating tube, protective sleeve and junction box and other components, and armored thermocouple is the thermocouple wire, insulation material and metal protection combination assembly sleeve three, a solid combination after stretching processing of. But the electric thermocouple needs a special wire to wire transfer, which we call the compensation wire. Different needs of different thermocouple compensation wire, its main function is to connect with the thermocouple, thermocouple reference junction away from the power, so that the reference junction temperature stability. The compensation wire is divided into compensation type and the extended type two kinds, chemical composition and the same extension wire is compensation of thermocouple, but in practice, the wire extension type is not using the same metal material and thermocouple, thermocouple wire generally used and replaced with the same electron density. Compensating conductor and thermocouple connections are generally very clear, thermocouple compensation wire connected to the anode of the red line, and the negative pole is connected to the rest of the color. The compensation wire general material mostly used copper nickel alloy.

Secondly, we introduce the heat resistance, heat resistance, although used in industry more widely, but because of his temperature range so that his application is subject to certain restrictions, the measuring principle of thermal resistance is the resistance of the conductor or semiconductor varies with temperature based on. Its advantages are many, can also remote signal, high sensitivity, strong stability, accuracy and interchangeability are good, but need power supply, can not change the instantaneous temperature measurement. Industrial thermal resistance generally use the Pt100, Pt10, Cu50, Cu100, platinum thermal resistance temperature measurement range is generally 200-800 Celsius degree, copper thermal resistance of minus 40 to 140 degrees celsius. Thermal resistance and thermocouple category, but he does not need compensation wire, but also cheaper than the thermocouple.


 Links:Shenzhen Kemin Sensor Co.,Ltd    Shenzhen Kemin Sensitive Components Co.,Ltd    Hangzhou Kemeit Sensor Co.,Ltd    NanJing Kemin Sensor Co.,Ltd    Shenzhen Kemin Institute Sensitive Components    YongKe(Hong Kong) Co.,Ltd
Copyright @ 2013 Shenzhen Kemin Sensor Co.,Ltd. AllRight Reserved
Tel:86 755 27308212/27307702/27308249/27307589 Fax:86 755 27307986