Historical
ANSI/NEMA PB 1.1-2013
General Instructions for Proper Installation, Operation and Maintenance of Panelboards Rated 600 V or Less
Covers single panelboards or groups of panel units suitable for assembly in the form of single panelboards, including buses, with or without switches or automatic overload protective devices (fuses or circuit breakers), or both. Specifically excluded are live-front panelboards, panelboards employing cast enclosures for special service conditions, and panelboards designed primarily for residential and light commercial service equipment.
NEMA: National Electrical Manufacturers Association [nema]