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Thermal Conductivity

Principle of Operation

Hitech thermal conductivity based analysers use a measuring technique developed and tested by them over the last 20 years. The primary sensor is called a katharometer. In construction it comprises two chambers, each with an identical thermal conductivity sensor. One chamber is sealed and is filled with a reference gas, and the other receives the sample gas. The difference in thermal conductivity of the reference and sample gases is translated into a concentration figure by the microprocessor circuitry within the electronics unit. The inherent stability of this system combined with precise temperature compensation; make the instrument one of the most accurate available. The diagram below shows the basic construction of a katharometer. When powered through suitable zener barriers, they can be located in hazardous areas. This is because the energy levels involved in powering the heated elements fall within the simple apparatus envelope.


Because this measurement is non-specific, it is necessary to assess each application taking into account details of the particular gas mixture it's required for. Please call us on +44 (0)1582 456900 or email us to let us know the details of your requirement.

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