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Temperature measurement technologies
Temperature can be measured in different ways. Depending on the application, various sensor technologies and measurement methods are used. In addition to classic contact measurements, non-contact infrared methods as well as monitoring and calibration concepts play an important role.
The following sections provide an overview of the most important technologies used in professional temperature measurement.
Temperature probes (NTC, Pt100/Pt1000, thermocouples)
Different sensor technologies each offer specific advantages. Resistance thermometers such as Pt100 or Pt1000 stand for high measurement accuracy and stability. Thermocouples are suitable for wide temperature ranges and fast measurements, while NTC sensors offer high sensitivity in the medium temperature range.
This section provides an overview of the most important sensor technologies and their areas of application.
How does an infrared thermometer work?
An infrared thermometer determines the temperature without touching the object being measured. Every material emits thermal radiation depending on its temperature. The measuring instrument captures this radiation with a sensor and converts it into a temperature value.
This method is particularly suitable for hot, moving or hard-to-reach surfaces. Typical applications include machine components, electrical installations or production processes.
Measurement accuracy depends strongly on the properties of the surface. An important parameter is the so-called emissivity. It describes how strongly a material emits thermal radiation.
In addition, measurement distance, ambient conditions and reflected radiation play a role. Particularly smooth or metallic surfaces can influence the measurement result and require careful adjustment of the measuring instrument.
Infrared measurement (surface, non-contact)
Non-contact temperature measurement captures the thermal radiation emitted by the object. The key factors are emissivity, spot size and ambient conditions. This section explains how infrared technology is used correctly.
What is the difference between Pt100 sensors and thermocouples?
Pt100 sensors are resistance thermometers. Their electrical resistance changes with temperature. This allows very accurate measured values to be determined, which is why these sensors are frequently used in laboratory and industrial applications.
Thermocouples work on a different principle: two different metals generate a small electrical voltage as soon as they are exposed to different temperatures. They are particularly robust and suitable for very high temperatures.
Contact measurement of surface temperatures
In contact measurement of surface temperatures, the probe is placed directly on the object being measured. This method is particularly suitable for components, machine parts or pipelines where precise temperature values are required. Depending on the application, special surface probes are used that enable a fast response and reliable measurement results.
Calibration & traceability
Measuring systems must be checked regularly to ensure accuracy and compliance with standards. Traceability to national standards is central to this. This page explains calibration concepts, inspection intervals and the importance of traceability for documented quality assurance.
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