C37.20.3-1987 - IEEE Standard for Metal-Enclosed Interrupter Switchgear
Description: The standard covers metal-enclosed interrupter switchgear assemblies containing such devices as interrupter/switches, selector switches, power fuses and protective equipment. It is concerned with enclosed, rather than open, switchgear assemblies rated above 1000 V used for the distribution of electrical power. It includes equipment that is part of primary and secondary unit substations.