Oakton WD-08517-75 - Type J Standard Air/Gas Probe

• Type J Standard Air/Gas Probe
• Designed with a perforated shield which allows air and other gases to flow into the sensor for quick readings
• Metal shield also absorbs radiated heat and minimizes sensor error
• Our sensors are encased in ceramic mineral (MGO) insulation to provide stability, and shock and vibration resistance

Thermocouple Probe Junction Types
Sheaths with small diameters have faster response times; sheaths with larger diameters have longer life and are better for measuring higher temperatures.

Exposed Junction

Exposed Junction has the fastest response time ideal for measuring rapid temperature changes. Clear coating on most models provides a humidity barrier for the thermocouple. Do not use with corrosive fluids or atmospheres.

Ungrounded Junction

Ungrounded Junction has a welded junction insulated from the protective sheath and is electrically isolated. Longer response time; use for conductive solutions or where isolation of the measuring circuitry is required.

Grounded Junction

Grounded Junction has a junction welded to tip of sheath. Wires are completely sealed from contaminants. Good response time.

Probe Shealth/Body Materials

Inconel® 600 Sheath is ideal for severely corrosive environments and elevated temperatures. Resists progressive oxidation. Maximum operating temperature: 1148°C (2100°F) continuous; 1371°C (2500°F) intermittent.

304 SS Sheath is for general-purpose use, is corrosion-resistant, and good for food service and biological applications. Maximum operating temperature: 898°C (1650°F) continuous; 1398°C (2550°F) intermittent.

316 SS Sheath has higher corrosion resistance than 304 SS. Withstands some strong acids. Maximum operating temperature: 898°C (1650°F) continuous; 1371°C (2500°F) intermittent.

SS Sheath with Coating of PTFE or PFA with grounded junction is ideal with corrosive liquids and atmospheres. Longer response time. Temperatures to 260°C (500°F).

Polymer Body Probes are available in a variety of polmyers including Kapton® and PTFE. These provide excellent flexibility and often good chemical resistance. Be sure to consult a chemical compatibility table when selecting a probe for your application.

General Considerations

Extend Your Thermocouples up to 2000 feet without signal loss. Extension wire must be the same type as the thermocouple.

System Error becomes important when you select a probe and meter to make a complete temperature measurement system. For example: a meter has an accuracy of ±0.7°F; probe error for the type T probe with metal sheath, straight cable, and stripped ends will have an error limit of ±1.8°F at 400°F. Therefore, the probe-meter system accuracy will be (±0.7) + (±1.8) = ±2.5°F at 400°F.

NIST traceability is required for many applications. In order to make an item traceable to NIST standards, the item and the standard are exposed to the same conditions, the readings are noted, and the difference between the readings is recorded on a NIST-traceable calibration report. When taking future readings with the item, the value on the report must be added or subtracted from the measured value.