UL 98:2019 PDF Download

The UL 98:2019 standard covers the requirements for enclosed air switches and deadfront switches. These switches are individually enclosed, with all current-carrying parts enclosed and manually operable by external handles. The standard applies to switches rated 4000 A or less at 1000 V or less and is intended to be used in accordance with national installation codes.

The standard also covers deadfront switches that have all current-carrying parts enclosed when mounted in an enclosed panelboard, deadfront switchboard, or similar equipment. These switches are manually operable and intended to be used in accordance with national installation codes.

The UL 98 standard covers enclosed switches with or without provision for fuses, suitable for use as branch circuit, feeder, and service overcurrent protection. The standard specifies various types of fuses that are deemed suitable for use with these switches.

Additionally, the standard differentiates between enclosed switches intended for general use and those intended for motor-circuit use only. It also covers double-throw switches for use in optional standby systems.

The UL 98 standard also includes requirements for fused electrically tripped switches and electrically tripped switches that have been investigated for ground-fault protection when combined with ground-fault sensing and relaying equipment.

However, it is important to note that the UL 98 standard does not cover common forms of snap switches, switches primarily intended for motor starting and protection, switches with automatic trips for overload protection, devices that use pulling of fuses for switching operations, or circuit breakers and other types of protection devices such as molded-case switches and supplementary protectors.