S type thermocouple is a kind of common measuring instrument, s type thermocouple, thermocouple is also known as precious metal has a certain application in multiple industries. Users in the use of s type thermocouple for it is the correct way of using the need to have a certain understanding, if the use of s type thermocouple method is not correct it is very easy to cause damage of s type thermocouple. I wire diameter of s type thermocouple regulation is 0. 5 mm, allowable deviation - 0. The positive (015 mm, sp) In the name of the chemical composition of platinum rhodium, contain the rhodium is 10%, platinum-based is 90%, the cathode ( sn) For pure platinum, commonly known as single platinum-rhodium thermocouple. The temperature is 1300 ℃, the long-term use of thermocouple short-term use temperature is 1600 ℃. S type thermocouple in the thermocouple series has high accuracy, stability, best measure [area wide, long service life, etc. Its physical and chemical performance is good, the thermoelectric potential stability and oxidation resistance at high temperature performance is good, suitable for oxidizing and inert atmosphere. Because of s type thermocouple has excellent comprehensive performance, in line with the international use of s type thermocouple temperature scale, has for a long time as an international scale interpolation instruments, 'its - Although 90 'provisions will not be as an international scale in check instruments, but the international advisory committee (temperature 有条件现金转移支付) S type thermocouple can still be used for approximate to realize international temperature scale. S type thermocouple deficiency is thermoelectric potential, thermoelectric potential rate is small, low sensitivity and mechanical strength under high temperature to drop, is sensitive to pollution, precious metal materials is expensive, and one-time investment is larger. S type thermocouple is also called single platinum-rhodium thermocouple, its index number is s degree, mainly measuring the temperature of 0 ~ 1600 ℃ medium, is one of the precious metal thermocouple category. Normal use in place of coking plant, steel plant and other high temperature use. S type thermocouple under normal use for a long time at about 800 ~ 1300 ℃ temperature measurement of high precision, and in 800 ℃ temperature measurement accuracy is not high, but the long-term use of temperature above 1300 ℃ can easily damage the thermocouple, so select the correct index number of thermocouple temperature measurement accuracy is the important factor.