Covers safety requirements for service-entrance, feeder, and branch-circuit busways and associated fittings rated 600 volts or less and intended for use in accordance with ANSI/NFPA 70-1981, National Electrical Code. Metal-enclosed bus for connecting switch gear assemblies for use in prefabricated electric distribution systems is not covered. These revised pages involve requirements for: (1) grounding of exposed dead metal parts; (2) tightening torque for field wiring terminals; (3) use of 75 degree C wire; (4) increased ampacity for conductors; (7) markings; and (8) overcurrent protection for trolley devices.
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)