What is the difference between type K and N thermocouple

Type K & N thermocouples are widely applied in temperature measurement . The positive Thermocouple wire for type K is NI/CR alloys, the negative Thermocouple wire is NI/SI(NI/AL) alloys. The positive Thermocouple wire for type N is NI/CR/SI alloys, the negative Thermocouple wire for type N is NI/SI/MGO alloys. Due to different composition of Thermocouple wire, they have different thermoelectric characteristic , physical and chemical capability.

Type K has better capability in Base Metal Thermocouple, which has good linearity , large thermoelectric power, high sensitivity, better stability and uniformity, good anti-oxidation and low price. But it has less stability in high temperature lead to slow drift for thermopotential,which will affect the measurement accuracy.

Type N is another normal type in Base Metal Thermocouple. It has better anti-oxidation and sulfur resistance than Type K .It’s generally used in wide range of temperature, which will have bigger non-linear deviation and slower hot response time. At temperature 300-500℃, it has better thermoelectric stability than Type K .

Accuracy and reliability of thermocouple measurement mostly decided by thermoeletric uniformity and stability of thermocouple materials. You need choose suitable thermocouple type according to specific applied situation and measuring requirements.

If you have any needs, please contact our professional engineers in SICC, we can offer professional advise and solutions.