Starting at $41.91
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  • Special mineral insulation protects thermocouple form moisture and thermal shock
  • Permits operation in high temperature and pressure environments
  • Small diameters are ideal when physical space or extremely fast response are critical
  • Flexible NACTPAK material allows forming and bending of the thermocouple
  • Outer sheath protects wires from oxidation and hostile environments
  • Wide range of sheath materials, diameters and calibrations to meet specific requirements


Watlow AC style mineral insulated standard plug thermocouples are fast-responding, durable, and capable of handling higher temperatures than non-insulated thermocouples.

Watlow AC style mineral insulated standard plug thermocouples are manufactured with XACTPAK®, Watlow's trademark for metal-sheathed, mineral insulated (MI) thermocouple material. XACTPAK® responds fast because the protective metal outer sheath allows the use of smaller diameter thermocouple conductors. The rock hard compacted MgO insulation further enhances the sensor's ability to "read" temperature by transferring heat quickly to the measuring junction.

The XACTPAK® protecting sheath and compacted insulation protects the Watlow AC style mineral insulated standard plug thermocouple from moisture, thermal shock, high temperatures, and high pressure, which allows these thermocouples to outperform their bare wire counterparts in most applications.

Watlow AC style mineral insulated standard plug thermocouples features mineral insulation for performance and plug or jack terminations that can be quickly connected or disconnected. Besides saving time, this thermocouple style offers the advantage of ease of use even by inexperienced personnel. In addition, Watlow AC style mineral insulated standard plug thermocouples are color coded per ASTM E 230 specifications so you can easily determine the calibration.

On all AC style thermocouples (except ASTM E 230 Type R and S) the pins and contacts are of the same alloy as the thermocouple, resulting in higher accuracy. this technique eliminates errors due to temperature gradients across the connector. Type R and S connectors have compensating alloys.

Applications for the Watlow AC Style Mineral Insulated Standard Plug Thermocouple

  • Heat treating
  • Furnaces/kilns
  • Turbines
  • Bearing temperature
  • Power stations
  • Steam generators
  • Diesel engines
  • Nuclear reactors
  • Atomic research
  • Jet engines and test cells
  • Rocket engines
  • Semiconductor manufacturing
  • Refineries/oil processing
  • Catalytic reformers
  • Food Processing