Type J Thermocouple, 1/4in OD, 12in Probe, 36in Teflon Leads

Type J Thermocouple | 1/4" OD, 12" Probe, 36" Teflon Leads

Product Overview

Thermocouples are the most popular, versatile, and cost-effective sensors used for temperature measurement across a vast range of industrial, scientific, and commercial applications. This particular model is a Type J thermocouple, recognized for its reliability and wide temperature range.

How Does a Thermocouple Work?

Thermocouples operate on the principle of the Seebeck effect. They convert thermal energy (heat) into a measurable electrical signal (voltage) that can be interpreted by process controllers, recorders, and data loggers. A thermocouple consists of two wires made from different metals, welded together at one end to form a "hot" junction. This is the sensing end that is placed in the environment to be measured. The other end, known as the "cold" or reference junction, is connected to the measuring instrument.

When the hot junction is heated, a temperature gradient is created along the wires, which generates a small voltage, or Electromotive Force (EMF). This voltage is directly proportional to the temperature difference between the hot and cold junctions. The instrument then measures this EMF and converts it into a precise temperature reading based on standardized calibration tables for the specific thermocouple type.

Construction and Materials

• Type J: This thermocouple is made from an iron wire and a constantan (copper-nickel alloy) wire. Type J is a common choice for its high sensitivity and cost-effectiveness in the mid-temperature range.
• Sheath: The 1/4" outer diameter (OD) probe is constructed from durable materials to protect the internal thermocouple wires from mechanical damage, corrosion, and harsh environmental conditions, ensuring a long service life.
• Insulation: Internally, the wires are insulated with Magnesium Oxide (MgO), a high-purity material that provides excellent electrical insulation and thermal conductivity, allowing for a rapid and accurate response to temperature changes.

Pyromation Quality

Pyromation is a leading manufacturer of temperature sensors, producing a comprehensive range of thermocouples designed for virtually any application. This includes standard general-purpose types, robust industrial assemblies, and specialized MgO-insulated models like this one. We also offer assemblies suitable for hazardous locations, which can be configured with connection heads, protective thermowells, and integrated transmitters to meet specific process requirements.

Product Specifications

• Thermocouple Type: J (Iron/Constantan)
• Junction Type: Ungrounded (Ung.) - The junction is electrically isolated from the outer sheath, providing a clean signal and protection against electrical noise.
• Probe Outer Diameter (OD): 1/4 inch
• Probe (Sheath) Length: 12 inches
• Probe Temperature Range: 0 to 760°C (32 to 1400°F)
• Transition: Standard transition with a spring for strain relief.
• Lead Wire: 36 inches of Teflon-insulated lead wire.
• Max Ambient Temp for Wire: 204°C (400°F) Continuous
• Wire Color Code (ANSI): Red (Negative) / White (Positive)
• Wire Termination: 2-inch stripped ends for easy connection to instrumentation.