Resistance thermometer with metallic protection tube

Resistance thermometer with metallic protection tube (50-WMS) are used for general temperature measurement, mostly in liquid and gaseous media at temperatures up to 600°C, on rare occasions up to 800°C.  Typical applications include refrigeration and air conditioning technology, heating, oven and apparatus construction, as well as chemical industry.


Protective fittings in this product line consist of seam welded or seamlessly drawn metal tubes.  Depending on the application, GÜNTHER GmbH has over 40 different, partly high-alloyed materials in a large array of measurements in stock.The tips for the protective tubes are either closed through hot forming or welded shut with a bottom blank.

Tapered measuring tips may be used in this product line in order to shorten the reaction time. For prolonging the holding time, strengthening the wall thickness and utilization of ceramic inner tubing are possible.

All internationally prevalent precision resistors, detachable process connectors (for example mobile flanges or threaded sleeves) and connection heads are used.

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 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.

The gauge slide in serial-production is fitted with a Pt 100 temperature sensor pursuant to DIN 60751, however versions with Pt 500 or Pt 1000 sensors are possible. The gauge slide is hermetically sealed.
For specialised applications (precision, long-term stability, etc.) we recommend the application of precision resistors with narrowed tolerance.
The resistance values and tolerances of our resistance thermometers are pursuant to DIN EN 60751.

Due to their structure, protected resistance thermometers offer a number of advantages when compared to regular thermocouple assemblies:

  • 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 by the enclosed structure

Application Examples for Resistance Thermometers with Metal Protection Tube

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

More Information on intrinsically safe temperature sensors