Thermocouple Bare Resistance Wire

NiCr-NiSi (Type K) thermocouple wire

NiSi (Type K) thermocouple finds the widest use in all base metal thermocouple, at temperature above 500°C.

The main chemical composition of  positive leg NiCr (KP) are Ni≈90% and Cr≈10%; negative leg NiSi (KN) are Ni≈97% and Cr≈3%. The operating temperature range is -200~1300°C(for short term) and 0~1100°C( for long term).

Type K thermocouple has strong resistance to oxidation than other base metal thermocouples. It has high EMF against Platinum 67, excellent temperature accuracy, sensitivity and stability, with a low cost. It is recommended for oxidizing or inert atmospheres

NiCr- CuNi(Constantan) thermocouple (Type E)

NiCr- CuNi thermocouple (type E) is also named NiCr- Constantan thermocouple. The main chemical composition of positive leg NiCr (EP) is Ni: Cr≈90:10; negative leg Constantan (EN) is Cu: Ni≈ 55%: 45%. Although EN, TN, JN are all called Constantan, EN and TN don not give the same EMF output curve as JN. EN and TN are able to interchange but they are not interchangeable with JN. The operating temperature range of type E thermocouple is -200~900°C.

Type E thermocouple has the largest EMF output and highest sensitivity, so it is ideal for measuring small temperature change. It also has good stability in the low temperature range up to 300°C, and good property of anti-corrosion in humidity atmosphere. It is recommended for oxidizing or inert atmospheres, but cannot be used directly in reducing atmosphere and atmosphere with sulphur gases.

Fe- CuNi(Constantan) thermocouple (Type J)

Fe-CuNi  thermocouple  (type J)  is also  named Fe- Constantan thermocouple.  The positive leg Fe(JP) is made by pure Iron, and the main chemical composition of negative leg Constantan (JN) is Cu: Ni≈ 55%: 45%. Although they are all called

Constantan, JN does not give the same EMF output curve as EN and TN, it cannot be instead by other Constantan.

The operating temperature range of type J thermocouple is -210~1200°C, but it is usually used in the temperature range 0~750°C due to embrittlement of Iron.

Type J thermocouple has good resistance to oxidation and high EMF output against Platinum 67, with good temperature accuracy, sensitivity and stability. It is recommended for vacuum, oxidizing, reducing or inert atmospheres,

but it can not be used in sulphurous atmosphere above 500°C.

Nicrsi-NisiMg (Type N) thermocouple

Nicrsi-NisiMg (Type N) thermocouple is the latest base metal thermocouple,

developed to improve the drawbacks that type K thermocouple has.

The main chemical composition of positive leg Nicrsi (NP) is Ni: Cr: Si≈84.4: 14.2: 1.4;

negative leg NisiMg (NN) is Ni: Si: Mg≈95.5: 4.4: 0.1. Type N thermocouple also be used in the similar atmospheres that

type K works, and the operating temperature range is -200~1300°C.

Type N thermocouple improves the EMF drift and short term EMF change, compared to type K thermocouple, and has a longer life than type K thermocouple. Therefore, in the industries where temperature control and measurement are especially critical, type N thermocouple has more advantages than other thermocouple as it has long life and stable thermal EMF.

Cu- CuNi (Constantan) thermocouple (Type T)

Cu-CuNi thermocouple (type T) is also named Cu- Constantan thermocouple.

The positive leg Cu(TP) is made by pure Copper, and the main chemical composition of negative leg Constantan (TN) is Cu: Ni≈ 55%: 45%.

Although EN, TN, JN are all called Constantan, TN and EN don not give the same EMF output curve as JN.  EN and TN are able to interchange but they are not interchangeable with JN.

The operating temperature range of type T thermocouple is -200~350°C, Due to the low resistance of oxidation that Copper has, it is not advisable to go beyond that range.

Type T thermocouple has good resistance to oxidation, high EMF output, with good

temperature accuracy, sensitivity and stability.

In the temperature range -200~0°C, it has better property, the year stability is less

than ±3μV

Manufacturing Flow

Factory Pictures