History
Electrical hazard and protection of persons (from etc172)
In the 18th century, the static electricity produced by friction caused some choc to experimenters. In 1780, by chance, Galvani observed the contraction of muscles by electricity of a frog leg.
In 1880: DC voltage 100 V rose to 1,300 V and then to 3,000 V (Grenoble-Vizille link in 1883) in order to transmit electricity over several kilometres. Insulation faults cause leaks and short-circuit.
In 1886: first distribution installation in the USA: 12 A/500 V/AC generator and 16 small transformers supply consumers with 100 V AC for the first time;
In 1889: AC and DC current wage war in North America (Edison (DC) – Westinghouse (AC))
In 1890: Kremler entered the electric chair and was electrocuted with... AC current! Thus, at the end of the 19th century, it was obvious to the technico-scientific community that electric current was dangerous for man, and that AC was more dangerous than DC.
