Traceability in power/reactive power measurements and assessment tests for “IEC555 power analyzers”, using the NPL Mk.III digital sampling wattmeter

This paper is intended as a review of the way NPL provides power traceability in the UK. It gives a description of the operation of the NPL Mk.III Digital Sampling Wattmeter (DSWM) which is the basis of the calibration service-for NAMAS laboratories, power companies and instrument manufactures. Descriptions are given of other uses of the DSWM including reactive power calibrations, low frequency ac measurements and the assessment of power analyzers which are designed to make measurements in conformance to IEC555