UL - 98
UL Standard for Safety Enclosed and Dead-Front Switches
|Publication Date:||27 April 1994|
These requirements cover individually enclosed air-break switches, having all current-carrying parts enclosed, manually operable by means of external handles, and intended to be employed in accordance with the National Electrical Code. They may have provisions for being tripped electrically.
These requirements also cover dead-front switches that have all current-carrying parts enclosed when mounted in an enclosed panelboard, dead-front switchboard or the like. These switches are manually operable by means of external handles or are hinged pullout switches and are intended to be employed in accordance with the National Electrical Code. A dead-front switch other than a hinged pullout switch may have provisions for being tripped electrically.
These requirements cover enclosed switches with or without provision for plug or for cartridge-enclosed fuses.
These requirements cover enclosed switches intended for general use and having ampere ratings, with or without horsepower ratings, and enclosed switches intended for motor-circuit use only and having horsepower ratings but no general use ampere ratings.
These requirements cover double-throw switches intended for use in optional standby systems in accordance with Article 702 of the National Electrical Code, ANSI/NFPA 70.
These requirements do not cover the common forms of snap switches; switches having features intended primarily for the starting and protection of motors, including the switches arranged to shunt out fuses during the starting of motors; switches provided with automatic trips for opening them and constructed to afford overload protection without other circuit breakers or fuses; or devices in which the pulling of fuses or the removal of a detachable pull-out member is designed to accomplish a switching operation.
As used in this standard, the term switch is intended to mean an enclosed switch or dead-front switch unless specifically stated otherwise.
A product that contains features, characteristics, components, materials, or systems new or different from those covered by the requirements in this Standard, and that involves a risk of fire, electric shock or injury to persons shall be evaluated using the appropriate additional component and end-product requirements as determined necessary to maintain the acceptable level of safety as originally anticipated by the intent of this Standard. A product whose features, characteristics, components, materials, or systems conflict with specific requirements or provisions of this Standard cannot be judged to comply with this Standard. Where considered appropriate, revision of requirements shall be proposed and adopted in conformance with the methods employed for development, revision and implementation of this Standard.