UL 1773:2020 PDF Download

A set of specifications known as UL 1773:2020 is applicable to termination boxes with a voltage rating of 600 to 1000 volts or less. These termination boxes are designed to be utilized in line with the National Electrical Code (NFPA 70), and they are made up of bus bars, terminal strips, or terminal blocks with space for wire connectors. The standard includes termination boxes that can be applied to service equipment's line or load side.

This standard's termination boxes can accommodate incoming and outgoing conductors, which can be routed through knockouts or apertures in the box for various forms of wiring such as cables, conduits, or electrical metallic tubing. Additionally, the termination boxes might have unique apertures made to line up with other electrical equipment like meter sockets, panelboards, switch or circuit breaker enclosures, wireways, and more that also have openings of a similar nature.

Both termination bases that can be field-installed in termination boxes and termination boxes in which termination bases are to be put in the field are covered by the UL 1773:2020 standard. The standard also includes mounting posts and pedestals with ratings of 600 to 1000 volts AC or less that are used as raceways for underground cabling that is elevated to supply outdoor electrical distribution equipment.

The standard does not apply to certain types of equipment, such as those connected to input and output circuits only by bus bars, equipment with switching components, relays, or overcurrent protection devices, busway fittings known as "End Cable Tap Boxes" (covered by UL 857), and inlet assemblies for generator cord connections used with transfer switch equipment (covered by UL 1008, Annex J, Inlet Assemblies for Transfer Switch Equip).