Which types are there for thermocouple? What are the characteristics for every type?

The thermocouple graduation has S, R, B, N, K, E, J, T and so on. S, R, B belong to expensive metal thermocouple, N, K, E, J, T belong to cheap metal thermocouple.
● S type thermocouple have characteristics of strong oxidation resistance, it can continuous use in oxidizing and inert gas, long-term operation temperature is 1400℃, short-term operation temperature is 1600℃, in all the thermocouples, S type thermocouple’s accuracy is the highest, it is usually used as a standard thermocouple.
● R type thermocouple’s electromotance is about 15% larger than that of S type thermocouple , other performance is almost the same as that of S type.
● B type thermocouple’s electromotance is very small at room temperature, so in the measurement, generally not need compensation wire. Its long-term operation temperature is 1600℃, short-term operation temperature is 1800℃. It can be used in oxidizing or neutral gas, or in vacuum for a short term using.
● N type thermocouple’s characteristic is that oxidation resistance is strong at high temperature 1300℃, thermoelectric electromotive force is stable for long-term; the recurrence of short-term thermal cycle is good; performance of anti-nuclear-radiation and low temperature resistance is good, can partly replace S type thermocouple.
● K type thermocouple’s characteristic is that oxidation resistance is strong, can continuous use in oxidizing and inert gas. Its long-term operation temperature is 1000℃, short-term operation temperature is 1200℃. It is the most widely used thermocouple.
● E type thermocouple’s electromotance is the largest in common used thermocouples, that is, its sensitivity is the highest. It can continuous use in oxidizing and inert gas, operation temperature is 0-800℃.
● J type thermocouple can be used in both oxidation gas (operation temperature upper limit 750℃), and reducing gas (operation temperature upper limit 950℃), it can resistant corrosion from H2 and CO, mostly used in oil refining and chemical industry.
● T type thermocouple’s accuracy is the highest among all cheap metal thermocouples, it is usually used to measure the temperature which is below 300℃.