This Standard applies to service-entrance@ feeder@ and branch-circuit busways and associated fittings rated at 600 V or less@ 6 000 A or less@ and intended for use in accordance with the Canadian Electrical Code@ Part 1 (CE Code@ Part 1)@ the National Electrical Code (NEC)@ NFPA 70@ and the Mexican Standard for Electrical Installations (Utility)@ NOM-001-SEDE (See Annex B@ Reference Item No. 1). These requirements do not apply to metal enclosed bus intended for connecting switchgear assemblies for use in prefabricated electric distribution systems. For the purpose of these requirements@ a busway is considered to be a grounded metal enclosure containing factory mounted conductors that are usually copper or aluminum bars@ rods@ or tubes. Deleted Values stated without parentheses are the requirement. Values in parentheses are explanatory or approximate information. Unless otherwise indicated@ all voltage and current values mentioned in this Standard are root-mean-square (rms).
2015UL 857 BULLETIN-2015 UL Standard for Safety Busways (COMMENTS DUE: July 24@ 2015)
2011UL 857 BULLETIN-2011 UL Standard for Safety Busways (COMMENTS DUE: February 21@ 2011)
2010UL 857 BULLETIN-2010 SUMMARY OF TOPICS The following changes in requirements to the Standard for Busways, UL 857, are being proposed: 1. Replace References to “Lighting Fixtures“ in Clauses 2.3.4.4.1 and 7.1.1.22 with “Luminaires“ 2. Add Marking Requirements for Fittings
2009UL 857 BULLETIN-2009 UL Standard for Safety Busways (COMMENTS DUE: November 25@ 2009)