N type, E type, what is the difference between several thermocouple J type specific _ instrument

N type nickel chromium silicon - Nickel silicon magnesium N type thermocouple nickel chromium silicon - Nickel thermocouple for inexpensive silicon magnesium metal thermocouple, is a standardized thermocouple, is developed in the early 70 s by Australian laboratory it overcome the K type thermocouple two important faults: K type thermocouple between 300 ~ 500 ℃ due to the lattice short-range order of nickel-chromium alloy thermoelectric emfs caused by unstable; At about 800 ℃ caused by nickel chrome preferential oxidation thermoelectric emfs instability. The anode ( NP） Chemical composition as follows: in the name of the Ni, Cr, Si = 84. 4:14. 2-1. 4, the cathode ( NN） In the name of the chemical composition is: Ni: Si, Mg = 95. Five. 4-0. For - 1, its working temperature 200~1300℃。 N type thermocouple has advantages of good linearity, thermoelectric emfs is larger, higher sensitivity, stability and good uniformity, oxidation resistance is strong, cheap, is not affected by short-range ordering etc, and its comprehensive performance is better than that of K type thermocouple, thermocouple is a kind of very promising. N type thermocouple cannot be directly used at high temperature, reducing or reduction, oxidation atmosphere and vacuum alternately, is not recommended for people with weak oxidizing atmosphere. （ E type thermocouple) Nickel chrome - Copper and nickel thermocouple nickel chrome - Copper and nickel thermocouple ( E type thermocouple) Also called nickel chrome - Constantan thermocouple, is also a kind of cheap metal thermocouple, the anode ( EP) Nickel chrome 10 alloy, chemical composition is the same as the KP, the cathode ( EN） For copper and nickel alloy, nominal chemical composition: 55% copper, 45% nickel and a small amount of manganese, cobalt, iron and other elements. Temperature for the use of the thermocouple 200~900℃。 E type thermocouple thermoelectric emfs, high sensitivity of all thermocouples, should be made of thermopile, measuring the temperature of the small change. Not very sensitive to high humidity atmosphere corrosion, appropriate is used in the environment of high humidity. E type thermocouple has good stability and oxidation resistance is better than that of copper - Lala, - of iron Constantan thermocouple, the advantages of cheap, can be used for oxidizing and inert atmosphere, is widely used for the user. E type thermocouple cannot directly at high temperature for sulfur, reducing atmosphere, the uniformity of the thermoelectric potential is poorer. Iron - J I J type Copper and nickel type thermocouple J I J - of iron Thermocouple is also called copper nickel iron - Constantan thermocouple, is also a kind of cheap cheap metal thermocouple. It's the positive ( 摩根大通(JP) In the name of the chemical composition of pure iron, the cathode ( 约) For copper and nickel alloy, has often been vaguely call constantan, its nominal chemical composition of: 55% copper and 45% nickel as well as small amounts of very important manganese, cobalt, iron and other elements, although it's called constantan, but differs from that of nickel and chromium - Constantan and copper - Constantan constantan, so can't use EN and TN to replace. Iron - Constantan thermocouple measuring temperature area for - 200 ~ 1200 ℃, but usually use temperature range of 0 ~ 750 ℃ J J type iron - Copper and nickel thermocouple has advantages of good linearity, thermoelectric emfs is larger, higher sensitivity, stability and uniformity is good, the advantages of cheap, widely used by users. J type thermocouple can be used in the vacuum, oxidation, reduction and inert atmosphere, but iron anode oxidation at high temperature quickly, so the temperature is restricted, cannot be directly without reserve for curing atmosphere at high temperature.