UL 891 BULLETIN

Abstract

Scope: Scope and object This Standard applies to switchboards nominally rated at 1 000 V or less and intended for use in accordance with the Canadian Electrical Code, Part 1 (CE Code, Part 1), the National Electrical Code (NEC), ANSI/NFPA 70, and the Mexican Standard for Electrical Installations (Utility), NOM-001-SEDE. In this standard the term switchboard is intended to refer to a dead-front switchboard. These requirements do not cover the following switchboard types: preset and dimmer control (theater), live front, railway control or electrification; or constructions intended only for receiving motor control center units. These requirements cover switchboards for use on circuits having available rms symmetrical short-circuit currents of not more than 200 000 A. These requirements do not cover switchboards with short-time current ratings