Accurate measurements over wide parameter ranges-a typical problem in industrial metrology and research

The SI units of physical quantities can be accurately realized and reproduced. The application of macroscopic quantum effects is an option for a highly improved reproduction of units. However, the measurement uncertainty over wide scale ranges can easily become unacceptably high. Proving traceability which is a general demand in establishing quality management systems according to ISO 9000 may then become a highly difficult task. This is of particular significance to industrial metrology and research where multiples and sub-multiples of the respective SI units occur. Typical examples of this in the characterization of electrical insulation are gigaohm, megavolt, micrometer, nanoampere or even picocoulomb. The evaluation and improvement of the measurement accuracy on scales are therefore topical research subjects in metrology. The author discusses the principles of basic metrology and the scaling problem including: the mass scale, temperature scale, length scale, electric resistance scale, capacitance scale, DC voltage scale, DC current scale, AC voltage scale, and the AC current scale