Low-voltage metal-enclosed switchgear-which contains either stationary or drawout, manually or electrically operated low-voltage ac or dc power circuit breakers in individual grounded metal compartments, in three-pole, two-pole, or single-pole construction-is covered. Rated maximum voltage levels are 254 V, 508 V, or 635 V (ac) and 300/325 V, 800 V, 1000 V, 1200 V, 1600 V, or 3200 V (dc). The standard deals with service conditions, ratings, temperature limitations, and classification of insulating materials, insulation (dielectric) withstand voltage requirements, test procedures, and application.
IEEE Std C37.20.1-2002 history
1970IEEE Std C37.20.1-2015 Armored low-voltage power circuit breaker switchgear (1000 volts and below, 3200 volts and below)