Sheath resistance thermometer without protection tube

Sheath resistance thermometer without protection tube (52-WOS) are used for general temperature measurement up to 600°C, on rare occasions up to 800°C. They are suited for surface temperature measurement as well as measurements of liquids and gases


Depending on the connection type (2-wire, 3-wire or 4-wire – in turn depending on the required measurement precision and connector length), resistance thermometers consist of 2, 4 or 6 copper feed lines (inner conductors), surrounded by a thin metallic protective mantle, usually made of high-grade steel.  The inner conductors are firmly press-fitted and insulated in ceramic powder. The precision resistor inside the sensor tip is connected through the inner conductors.
As a result of their structure, mineral insulated resistance thermometers have the following advantages:

  • Small physical dimensions with maximum flexibility for temperature measurement at sites with difficult accessibility (diameter 1,5 – 6,0 mm)
  • Short response time for exact measurements of temperature variations
  • Optimal protection for the sensor system against corrosion, oxidation, phyiscal damage and chemical contamination as a result of the enclosed structure
  • The enclosed structure also facilitates application of these sensors without additional protective fitting

Application Examples for Mineral Insulated Resistance Thermometers without Protection Tube


We offer every current version and diameter of mineral insulated resistance thermometer with mounted plug-and-socket connectors, connector heads, compensation lines with or without specialised contacts, as well as accessories and every type of mounting.

Our resistance thermometers are also available in explosion protected ATEX models.

More Information on intrinsically safe temperature sensors