Environmental Requirements for Electromechanical and Electrical Equipment

SI units for existing technology

As Gregor M. Grant explained in his article published in the April/May 1997 issue of Electro Technology, the Système International d’Unités (SI) was a child of the 1960s, a creation of the 11th General Conference on Weights and Measures (Conférence Générale des Poids et Mesures (CGPM)). This assembly endorsed the Italian physicist Professor Giovanni Giorgi’s MKS (i.e. metre-kilogram-second) system of 1901 and decided to base the SI system on it. Seven basic units were adopted, as shown in Table A, each of which was harmonised to a standard value.

Table A

Basic SI units

SI nomenclature	Abbreviation	Quantity
metre	m	length
kilogram	kg	mass
second	s	time
ampere	A	electrical current
kelvin	K	temperatures ...