Type J thermocouple wire, Fe-CuNi

Thermocouple wire Type J is a widely used thermocouple junction. In general, it is economically priced and it has a smaller temperature range compared to other thermocouple junctions: -210°C .. +750°C.

Type J, Fe-CuNi thermocouple is a widely used thermocouple junction. In general, it is economically priced and it has a smaller temperature range compared to other thermocouple junctions: -210°C to +750°C. Type J thermocouples are favored for their low cost and high EMF, making them suitable for industrial applications.

These thermocouple wires feature iron-constantan conductors but have a slightly smaller temperature range compared to type K thermocouples and are not ideal for oxidizing environments. Caution is advised as the iron leg can rust if exposed to moisture.

In short;

  • is available in diameters ranging from 0.80 mm to 3.90 mm
  • is provided in EN 60584 Class 1
  • is supplied with an 3.1 certificate and a calibration certificate
  • is supplied with positive and negative leg
  • is a good choice for reducing or inert environments or in a vacuum with temperatures up to 750°C

Our standard wire items

ThermocoupleClassOutside Diameter in mmOn Stock
Type J wireClass 10.30 mm5 week delivery timeSend inquiry
Type J wireClass 10.80 mm5 week delivery timeSend inquiry
Type J wireClass 10.80 mmYesSend inquiry
Type J wireClass 11.00 mmYesSend inquiry
Type J wireClass 11.50 mm5 week delivery timeSend inquiry
Type J wireClass 12.00 mmYesSend inquiry
Type J wireClass 13.00 mm5 week delivery timeSend inquiry
Delivery times stated are for delivery to Kamet’s warehouse

Please contact us if you need different diameters. We can supply more custom made diameters (combinations) than stated above.

Operating temperature

Approximate working temperature tange;

  • Continues: +20 to +700°C
  • Short term: –180 to +750°C

Please note that these ranges are given as indicative values and vary per diameter.

Chemical composition

AlloyFeNiCu
JP ( + )100
JN (-)4555

Physical properties

JPJN
Density (g/cm3)7.868.90
Melting point (°C)15351210
Resistivity15351210
Temp. coef. of resistance (x10-6/°C)500060
Linear expansion (coef. x10-6/°C)11.714
Thermal Conductivity (W m-1 °C-1 at 20°C)66.221.2

Environment and industrial usage

Type J thermocouples are versatile instruments primarily used for temperature monitoring in various applications. They are particularly suitable for vacuum environments, for monitoring inert metals and non-reactive materials such as sand, concrete, and asbestos-containing materials. These thermocouples excel in high-temperature processes, including the manufacturing of plastics and resins.

However, they are not recommended for use in sulphurous atmospheres above 500°C or in oxidizing atmospheres at high temperatures due to the risk rust.

JP/JN EMF reference table (mV)

°C0102030405060708090100
000.5071.0191.5362.0582.5853.1153.6494.1864.7255.268
1005.2685.8126.3596.9077.5478.0088.569.1139.66710.22210.777
20010.77711.33211.88712.44212.99813.55314.10814.66315.21715.77116.325
30016.32516.87917.43217.98418.53719.08919.6420.19220.74321.29521.846
40021.84622.39722.94923.50124.05424.60725.16125.71626.27226.82927.388
50027.38827.94928.51129.07529.64230.2130.78231.35631.93332.51333.096
60033.09633.68334.27334.86735.46436.06636.67137.2837.89338.5139.13
70039.1339.75440.38241.01341.64742.28342.92243.56344.20744.85245.498
80045.49846.14446.7947.43448.07648.71649.35449.98950.6251.24951.875

Get an quote!

Do you have any further questions? Please let us know and our specialists will be happy to advise you.


Other products in this category
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