Type J Thermocouples

UK Manufactured Type J Thermocouple

Type J Thermocouple is a Base metal thermocouple made from conductors containing Iron, and Copper – Nickel alloys and is suited for measuring temperatures up to +750°C. We manufacture J type thermocouples to your specifications or as replacements to existing sensors. We have manufactured thermocouples for over 15 years and are solely focused on the design and manufacture of temperature sensors. Please call or email us to discuss your requirements.

Need some help?

If you are unsure exactly what you need, get in touch and we can help identify your requirements.

Type J Thermocouple Designs

Thermocouples can come in a variety of designs suited to different applications. View the details of each type of design we offer for thermocouples Type J.

Thermocouple Type J Technical Details

Type J thermocouples are good in both reducing and oxidizing atmospheres. Type J has a slightly higher sensitivity than Type K at about 50 µV/°C.

J type thermocouple sensor is a very common type. It is most suited for lower temperatures than Type K at a similar cost.

J Type Thermocouple Temperature Range


0 to +700 °C

Short Term:

-180 to +800 °C

J Type Thermocouples Material

Iron (Fe)

Constantan (55%Cu, 45%Ni)

Type J Thermocouples Tolerance Details

Tolerance Class 1

-40 to +375 ± 1.5 °C

375 to 750 ± 0.004*[t]°C

Tolerance Class 2

-40 to +333 ± 2.5 °C

333 to 750 ± 0.0075*[t]°C

Type J Thermocouples Colour Codes

IEC Colour Code

Type J IEC Cable Colour Coding

BS Colour Code

Type J BS Cable Colour Coding

ANSI Colour Code

Type J ANSI Cable Colour Coding

Contact us

We’ve made Type J Thermocouples for over 25 years and today we are considered the best choice for custom built temperature sensors in the UK. We continue to apply our expertise and invest in the latest technology to provide our customers with the highest quality temperature sensors available.

Contact us with your requirements if you have an existing sensor design or are unsure what you need we’ll be able to find you get the right sensor for your process.

Submit an Enquiry

"*" indicates required fields

This field is for validation purposes and should be left unchanged.
    Your Basket
    Your basket is emptyReturn to Shop
        Scroll to Top