Although the application of thermal resistance in the industry is also more extensive, but due to his temperature range makes his application has been limited, the thermal resistance temperature measurement principle is based on the conductor or semiconductor resistance value changes with temperature changes characteristic. Its advantages are also many, it can also transmit remote signals, high sensitivity, strong stability, interchangeability and accuracy are better, but the need for power excitation, can not be instantaneous measurement of temperature changes. Industrial thermal resistors generally use Pt100, Pt10, Cu50, Cu100, platinum thermal resistance temperature measurement range is generally below 200-800 °C, copper thermal resistance is minus 40 to 140 °C. Thermal resistance is the same type of discrimination as thermocouples, but he does not need compensating wires and is cheaper than thermocouples. Silica Aerogel Powders,Silica Aerogel Thermal Insulation Coating,Aerogel Incorporated Plasters And Mortars,Aerogel Insulating Plaster Henan Minmetals East New Materials CO. LTD. , https://www.minmetals-easts.com
Shanghai Feilong Instrument Electric Co., Ltd. is one of the high-paid technology companies in the region. The series of temperature-controlled electronic products jointly developed and produced by Shanghai's many scientific research institutes and institutions are sold throughout the country. The company's main products are: probe surface thermocouples , chemical flameproof thermocouples , WRNM surface thermocouple probes , fixed threaded thermocouples and so on. Products are known for their excellent performance, beautiful appearance, high reliability, and good price/performance ratio, winning the trust of users. Has passed ISO9001: 2000 quality system certification, the company has a first-class production lines and testing methods, the implementation of the entire process of quality supervision. The company has a strong technical development lineup and patent results, willing to undertake regular and special specifications of the product business. Can design and install various large, medium and small automatic temperature control systems for customers.
Thermocouple is the most widely used temperature device for temperature measurement. Its main features are wide temperature measurement range, stable performance, simple structure, good dynamic response, and can transmit 4-20mA electrical signals remotely, facilitating automatic control and concentration. control. Thermocouple temperature measurement principle is based on the thermoelectric effect. Connecting two different conductors or semiconductors into a closed loop, when the temperature at two junctions is different, a thermoelectric potential will be generated in the loop. This phenomenon is called the thermoelectric effect, also known as the Seebeck effect. The thermoelectric potential generated in a closed loop has two potential components: a thermoelectric potential and a contact potential. Thermoelectric potential refers to the potential generated at the two ends of the same conductor due to different temperatures. Different conductors have different electron densities, so the potentials they generate are also different. The contact potential, as the name implies, means that two different conductors are in contact. Because their electron density is different, they produce a certain amount of electron diffusion. When they reach a certain equilibrium, the potential formed depends on the material properties of the two different conductors and the temperature of their contact points. At present, thermocouples used in the world have a standard specification. Internationally, thermocouples are divided into eight different divisions, namely B, R, S, K, N, E, J, and T. The lowest measurement temperature is available. Zero under 270 °C, up to 1800 °C, of ​​which B, R, S platinum series of thermocouples, because platinum is a precious metal, so they are also known as the precious metal thermocouple and the remaining few are called cheap metal thermoelectric I. There are two types of thermocouples, common type and armor type. General thermocouples are generally composed of hot electrodes, insulating tubes, protective tubes, and junction boxes. Armored thermocouples are assembled by combining thermocouple wires, insulating materials, and metal protective tubes. Extensive processing of a solid combination. But the electric signal of the thermocouple needs a kind of special wire to transmit, this kind of wire is called compensating wire. Different thermocouples require different compensating conductors, whose main function is to connect with the thermocouple, and keep the reference end of the thermocouple away from the power source, thereby stabilizing the temperature of the reference junction. Compensation wire is divided into compensation type and extension type. The chemical composition of the extension wire is the same as that of the compensated thermocouple. However, in practice, the extension wire is not the same material as the thermocouple. Generally, the heat wire is used. Even the wires with the same electron density are replaced. The wire of the compensation wire and the thermocouple is generally very clear. The positive pole of the thermocouple connects the red wire of the compensation wire, and the negative pole connects the remaining colors. Most of the material of the general compensation wire is copper-nickel alloy.