Thermocouples above 600°C: Infra-Red Thermometers and Optical Pyrometers

Abstract

This paper outlines the important features in the calibration of all types of thermocouples and infra-red thermometers using the established methods of calibration. The International Practical Temperature Scale of 1968 is described with reference to the fixed points and methods of interpolation between them. The principle of traceability is described and also the various traceability routes via Absolute, Secondary and Transfer Standards which can be employed.

Importance is placed on the provision of written procedures, schedules for routine checking and maintenance of full and accurate records. This work should be the responsibility of a co-ordinating expert. Descriptions are given of temperature sources and ancilliary equipment necessary for establishing a works laboratory which requires traceability to National Standards. The normally attainable levels of uncertainty are given for a number of examples.

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References

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