Type J Thermocouples
Learn more about our 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.
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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.
- Mineral Insulated Type J – Metal sheath insulated with magnesium oxide powder also called MIMS.
- Cable/Wire Type J – Flexible sensors in PVC, PTFE or Glass Fibre. Many cold and hot-end designs.
- Type J with Ceramic Sheaths – High-temperature design with ceramic protection sheath
- Type J with Metal Sheaths – High-temperature design with metal protection sheath
- Type J Inserts – Rigid metal tubes commonly used in pocket, thermowell or head assemblies.
- Type J Elements – Basic elements for further assembly into sheaths or equipment.
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
-180 to +800 °C
Constantan (55%Cu, 45%Ni)
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
IEC Colour Code
BS Colour Code
ANSI Colour Code
We’ve made Type J Thermocouples for over 15 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.