The 1957 South African developments in sensitive earth leakage protection signalled a quantum leap in the science and application of devices specifically intended to improve the usability of electrical power, by dramatically reducing electrical shockand fire hazards resulting from imperfect or damaged electrical circuits. Twenty five years of installation experience and evolution technology in these devices resulted in the 1982 edition of the SABS product standard SABS 767, which replaced the original 1964 document. By that time, sufficient understanding of application requirements and idiosyncrasies had been identified to enable documentation of the application and design limitations of Earth Leakage Circuit Breakers (ELCB's).
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