Fe-CuNi Type J Thermocouple Wire for Industrial Processes with Moderate Temperatures

Fe-CuNi Type J Thermocouple Wire is a widely used thermocouple material composed of a positive leg made of pure iron (Fe) and a negative leg made of Copper-Nickel alloy (CuNi), commonly known as Constantan. Type J thermocouples are known for their affordability, high sensitivity, and effective use in moderate temperature ranges, especially in environments free from oxidizing conditions.

Fe-CuNi Type J Thermocouple Wire is a cost-effective and reliable solution for moderate-temperature applications. Its high sensitivity, affordability, and stable performance make it a popular choice for industrial heating, temperature monitoring, and general-purpose uses in environments free of oxidizing or corrosive conditions.

color codes of thermocouple ( J type )

Thermocouple temperature range and tolerance

Key Features of Fe-CuNi Type J Thermocouple Wire:

• Temperature Range

Effective in temperatures ranging from -210°C to 760°C (-346°F to 1400°F), making it suitable for low-to-moderate temperature applications.

• High Sensitivity

Produces a thermoelectric voltage of approximately 55 µV/°C at 0°C, ensuring accurate temperature readings.

• Material Composition

Positive Leg (Fe): Made of pure iron for consistent performance.

Negative Leg (CuNi/Constantan): Approximately 55% Copper and 45% Nickel.

• Electrical Properties

Provides stable and reliable thermoelectric output within its operating range.

• Cost-Effective

Economical compared to other thermocouple types, making it ideal for general-purpose applications.

• Corrosion Resistance

Resistant to oxidation in reducing or vacuum environments.

Not suitable for oxidizing environments at high temperatures, as iron is prone to rapid oxidation.

• Applications

Widely used in industrial heating processes, kilns, and furnaces.

Common in applications such as temperature monitoring in oil and gas, chemical processing, and power generation.

• Cable Options

Available in bare wire, insulated wire, or cable forms with various insulation materials such as fiberglass, Teflon, or ceramic.

Shielded cables are available for use in electrically noisy environments.

Advantages of Type J Thermocouple Wire:

• High sensitivity provides accurate readings within its temperature range.
• Cost-effective option for general-purpose use.
• Performs well in reducing or vacuum environments.

Limitations:

• Not recommended for use in oxidizing or high-humidity environments, as the iron leg corrodes quickly.
• Limited upper temperature range compared to other types, such as Type K.
• Magnetic properties of the iron leg can cause issues in certain applications.