Column: Standards relevant to transformers – Part I
Standards are formulated to meet the generally recognised demands, minimum performance and safety requirements, as well as to make sure that the product from different manufacturers is similar and consistent. A survey is done on the evolution of national standards for transformers and of the range of IEC / IEEE standards available today for transformer engineers. Of course, standards are dynamic and are under continuous revisions and additions. Hence, no claim is made that the listings provided are the latest or include all relevant standards connected with transformers. A listing of standards, if made, as in this contribution in groups – viz. Application guides, Specification, Testing, Transformer Oil, Accessories, Raw Materials, Installation, Operation, Maintenance and Protection, with relevant IEC and IEEE standard numbers for each subject – will be useful as a quick reference for transformer engineers engaged in the selection, procurement, manufacturing, testing, installation, operation, maintenance, and protection of transformers. A list of CIGRE technical brochures relevant to transformers is also included.
It took 52 years from Faraday’s discovery of electromagnetic induction to the first AC electrical power system that uses transformers
Genesis of transformer
Michael Faraday discovered electromagnetic induction on 29th August 1831 by winding two pairs of windings on a soft iron ring of 6 inches outer diameter and 7 / 8 inches thickness – the forerunner of a modern electrical transformer. When he supplied current from a battery to one pair of windings, he found momentary deflection of a magnetic needle located near the shorted winding on the opposite side of the iron ring. But it took another 52 years for AC electric power transmission to come into practice using transformers. The first AC distribution line came into London in 1883 when secondary generators (the term used for transformers then) were used in a 12 KMs underground line for lighting. The first AC transmission line was erected for the Turin-Lanzo Railway line, Turin, Italy in 1884 using Gaulard and Gibbs converters. Modern transformers with a closed magnetic path and parallel-connected primaries were demonstrated in 1885 at the industrial exhibition of Budapest for public lighting using Ganz, Hungary made transformers, and in 1886 in Great Barrington, Massachusetts, the USA, using William Stanley transformers. As the volume of transformer production increased at various centres, the need was felt in all countries for standardising the ratings, voltage, and testing of transformers and other electrical machinery.