What is the difference between k-type and j-type thermocouples?
The overview is different:
1. K-type thermocouple: It is a temperature sensor, usually used in conjunction with display instruments, recording instruments and electronic regulators.
2. J-type thermocouple: Also known as iron-constantan thermocouple, it is a cheap and inexpensive metal thermocouple.
The composition is different:
1. K-type thermocouples are usually composed of main components such as temperature sensing elements, installation fixtures and junction boxes.
2. J-type thermocouple: the nominal chemical composition of the positive electrode (JP) is pure iron, and the negative electrode (JN) is a copper-nickel alloy, which is often vaguely called constantan, and its nominal chemical composition is: 55% copper and 45% copper. % nickel and a small but very important amount of manganese, cobalt, iron and other elements.
Features are different:
1. Features of K-type thermocouple:
a. High accuracy.
b. Wide tempearture range.
c. Simple structure and easy to use.
2. Features of J-type thermocouple:
a. Good linearity.
b. Large thermal electromotive force.
c. High sensitivity.
d. Good stability and uniformity.
c. Cheap price.
2.J-type thermocouples can be used in vacuum, oxidizing, reducing and inert atmospheres, but the cathode iron oxidizes faster at high temperatures, so the use temperature is limited, and it cannot be directly used in vulcanizing atmospheres at high temperatures without protection.
