Perhaps this is stuff that has been hashed and rehashed at
USITT before, but since you're asking…
I have been going through the 2014
NEC and have a few questions that I would be interested in clarification on:
520.63 Bracket
Fixture Wiring
(A) Bracket Wiring. Brackets for use on scenery shall be wired internally, and the
fixture stem shall be carried through to the back of the scenery where a
bushing shall be placed on the end of the stem. Externally wired brackets or other fixtures shall be permitted where wired with cords designed for hard usage that extend through scenery and without joint or splice in canopy of
fixture back and terminate in an approved-type
stage connector located, where
practical, within 450 mm (18 in.) of the
fixture.
Question: Does this mean that sconces,
etc. that are mounted to scenery cannot be wired with
zip cord, but must be wired with (at minimum) 18
gauge SJ cable that that terminates in a
stage pin or
twist lock connector within 18"?
I am operating under premise of the information found in table 400.4 that
SPT cable (
lamp cord) is "not hard usage", that SJ cable qualifies as "hard usage", and that SO qualifies as "extra-hard usage". There doesn't seem to be any requirement here that the cable be of a capacity any larger than is necessary for the
practical (usually 100 watts or less).
A related question: I can't seem to find any information regarding "listed" practicals. By this I mean a
UL-listed table or floor lamp that is wired with
SPT cable that terminates in a molded 2-prong
Edison plug. Does this type of
practical need to connect directly to a 12
gauge SO cable without any sort of intermediate
cord even when such an installation would prove to be unsightly or very difficult to achieve because of the physical size of 12
gauge SO cable?
As a side note, I want to thank all involved who are staying on top of the
NEC issues and especially to Steve Terry for his many submissions regarding article 520 venues for consideration for the 2017
NEC.
Mark Kieffer