ARTICLE 530 – MOTION PICTURE AND
TELEVISION STUDIOS AND SIMILAR LOCATIONS
A.
General
530-1. Scope.
The requirements of this article shall apply to television studios and motion
picture studios using either film or electronic cameras, except as provided in
Section 520-1, and exchanges, factories, laboratories, stages, or portion of the
building in which film or tape more than 7/8 in. (22 mm) in width is exposed,
developed, printed, cut, edited, rewound, repaired, or stored.
(FPN): For methods of
protecting against cellulose nitrate film hazards, see Standard for the
Storage and Handling of Cellulose Nitrate Motion Picture Film, NFPA 40-1994
530-2 Definitions.
AC Power Distribution Box (AC Plugging Box, Scatter Box): An ac
distribution center or box that contains one or more grounded, polarized
receptacles, that may contain overcurrent protection devices.
Bull Switch: An externally-operated wall mounted safety switch, which may
or may not contain overcurrent protection, that is designed for the connection
of portable cables and cords.
Location (Shooting Location): A place outside a motion picture studio
where a production or part of it is filmed or recorded.
Location Board (Deuce Board): Portable equipment containing a lighting
contactor or contactors and overcurrent protection designed for remote control
of stage lighting.
Motion Picture Studio (Lot): A building or group of buildings and other
structures designed, constructed, or permanently altered for use by the
entertainment industry for the purpose of motion picture or television
production.
Portable Equipment: Equipment intended to be moved from one place to
another.
Plugging Box: A dc device consisting of one or more 2-pole, 2-wire,
nonpolarized ungrounded receptacles intended to be used on dc circuits only.
Single-Pole Separable Connector: A device that is installed at the ends
of portable, flexible, single-conductor cable that is used to establish
connection or disconnection between two cables or one cable and a single-pole,
panel-mounted separable connector.
Spider (Cable Splicing Block): A device that contains busbars that are
insulated from each other for the purpose of splicing or distributing power to
portable cables and cords that are terminated with single-pole busbar
connectors.
Stage Effect (Special Effect): An electrical or electromechanical piece
of equipment used to simulate a distinctive visual or audible effect such as
wind machines, lightning simulators, sunset projectors, and the like.
Stage Property: An article or object used as a visual element in a motion
picture or television production, except painted backgrounds (scenery) and
costumes.
Stage Set: A specific area set up with temporary scenery and properties
designed and arranged for a particular scene in a motion picture or television
production.
Stand Lamp (Work Light): A portable stand that contains a general-purpose
lighting fixture or lampholder with guard for the purpose of motion picture,
television, or commercial production.
530-11. Permanent Wiring.
The permanent wiring shall be Type MC cable, Type MI cable, or in approved
raceways.
Exception: Communications circuits, sound-recording and reproducing circuits,
Class 2 and Class 3 remote-control or signaling circuits and power-limited fire
alarm circuits shall be permitted to be wired in accordance with Articles 640,
725, 760, and 800.
530-12. Portable Wiring.
The wiring for stage set lighting, stage effects, electric
equipment used as stage properties, and other wiring not fixed as to location
shall be done with approved flexible cords used to supply stage properties where
such are made with approved devices and the circuit is protected at not more
than 20 amperes. Such cables and cords shall not be fastened by staples or
nailing.
530-13. Stage Lighting and Effects Control.
Switches used for studio stage set lighting and effects (on the stages and lots
and on location) shall be of the externally operable type. Where contactors are
used as the disconnecting means for fuses, an individual externally operable switch, such
as a tumbler switch, for the control of each contactor shall be located at a
distance of not more than 6 ft (1.83 m) from the contactor, in addition to
remote-control switches.
530-14. Plugging Boxes.
Each receptacle of dc plugging boxes shall be rated at not less than 30 amperes.
530-15. Enclosing and Guarding Live Parts.
(a)
Live Parts. Live parts shall be enclosed or guarded to prevent
accidental contact by persons and objects.
(b)
Switches. All switches shall be of the externally operable type.
(c)
Rheostats. Rheostats shall be placed in approved cases or cabinets
that enclose all live parts, having only the operating handles exposed.
(d)
Current-Carrying Parts. Current-carrying parts of bull-switches,
location boards, spiders, and plugging boxes shall be so enclosed, guarded, or
located that persons cannot accidentally come into contact with them or bring
conductive material into contact with them.
530-16. Portable Lamps.
Portable lamps and work lights shall be equipped with flexible cords,
composition or metal-sheathed porcelain sockets, and substantial guards.
Exception: Portable lamps used as properties in a motion picture set or
television stage set, on a studio stage or lot, or on location.
530-17. Portable Arc Lamp Fixtures.
(a) Portable
Carbon Arc Lamps. Portable carbon arc lamps shall be substantially
constructed. The arc shall be provided with an enclosure designed to retain
sparks and carbons and to prevent persons or materials from coming into contact
with the arc or bare live parts. The enclosures shall be ventilated. All
switches shall be of the externally-operable type.
(b)
Portable Noncarbon Arc Electric-Discharge Lamp Fixtures. Portable
noncarbon arc lamp fixtures, including enclosed arc lamp fixtures, and
associated ballasts shall be listed. Interconnecting cord sets, and
interconnecting cords and cables, shall be extra-hard usage type and listed.
530-18. Overcurrent Protection.
General. Automatic overcurrent protective devices (circuit breakers or
fuses) for motion picture studios stage set lighting and the stage cables for
such stage set lighting shall be as given in (a) through (f) below. The maximum
ampacity allowed on a given
conductor, cable, or cord size shall be as given in applicable tables of Article
310 and 400.
(a)
Stage Cables. Stage cables for stage set lighting shall be
protected by means of
overcurrent devices set at not more than 400 percent of the ampacity given in applicable tables of Articles 310 and 400.
(b)
Feeders. In buildings used primarily for motion picture
production, the feeders from the substations to the stages shall be protected by
means of overcurrent devices (generally located in the substation) having
suitable ampere rating. The overcurrent devices shall be permitted to be
multipole or single-pole gang-operated. No pole or over current device shall be
required in the neutral conductor. The overcurrent device setting for each
feeder shall not exceed 400 percent of the ampacity of the feeder, as given in
applicable tables of Article 300.
(c)
Location Boards. Overcurrent protection (fuses or circuit
breakers) shall be provided at the location boards. Fuses in the location boards
shall have an ampere rating of not over 400 percent of the ampacity of the
cables between the location boards and the plugging boxes.
(d)
Plugging Boxes. Cables and cords supplied through plugging boxes
shall be of copper. Cables and cords smaller than No. 8 shall be attached to the
plugging box by means of a plug containing two cartridge fuses or a 2-pole
circuit breaker. The rating of the fuses or the setting of the circuit breaker
shall not be over 400 percent of the rated ampacity of the cables or cords as
given in applicable tables of Articles 310 and 400. Plugging boxes shall not be
permitted on ac systems.
(e)
AC Power Distribution Boxes. AC power distribution boxes used on
sound stages and shooting locations shall contain connection receptacles of a
polarized grounding type.
(f)
Lighting. Work light, stand lamps and fixtures, rated 1,000 watts
or less and connected to dc plugging boxes, shall be by means of plugs
containing two cartridge fuses not larger than 20 amperes, or they shall be
permitted to be connected to special outlets on circuits protected by fuses or
circuit breakers rated at not over 20 amperes. Plug fuses shall not be used
unless they are on the load side of the fuse or circuit breakers on the location
boards.
530-19. Sizing of Feeders Conductors for Television Studio Sets.
(a) General.
It shall be permissible to apply the demand factors listed inTable 530-19(a) to
the portion of the maximum possible connected load for studio or stage set
lighting for all permanently installed feeders between substations and stages
and to all permanently installed feeders between the main stage switchboard and
stage distribution centers or location boards.
(b)
Portable Feeders. A demand factor of 50 percent of maximum
possible connected load shall be permitted for all portable feeders.
Table 520-19(a). Demand Factors for Stage Set Lighting
530-20. Grounding.
Type MC cable, Type MI cable, metal raceways, and all noncurrent-carrying metal
parts of appliances, devices, and equipment shall be grounded as specified in
Article 250. This shall not apply to pendant and portable lamps, to stage
lighting and stage sound equipment, nor to other portable and special stage
equipment operating at not over 150 volts dc to ground.
530-21. Plugs and Receptacles.
(a) Rating.
Plug and receptacles shall be rated in amperes. The voltage rating of the plugs
and receptacles shall not be less than the circuit voltage. Plug and receptacle
ampere ratings for ac circuits shall not be less than the feeder or branch
circuit over current device ampere rating. Table 210-21(b)(2) shall not apply.
(b)
Interchangeability. Plugs and receptacles used in portable professional
motion picture and television equipment shall be permitted to be interchangeable
for ac or dc use on the same premises provided they are listed for ac/dc use and
marked in a suitable manner to identify the system to which they are connected.
530-22 Single-Pole Separable Connectors.
Where ac single-pole portable cable connectors are used, they shall be listed
and of the locking type. Where paralleled sets of current carrying single-pole
separable connectors are provided as input devices, they shall be prominently
labeled with a warning indicating the presence of internal parallel connections.
The use of such connectors shall comply with at least one of the following
conditions:
(1) Connection
and disconnection of connectors are only possible where the supply connectors
are interlocked to the source and it is not possible to connect or disconnect
connectors when the supply is energized.
(2)
Line connectors are of the listed sequential-interlocking type so that
load connectors shall be connected in the following sequence.
(a)
Equipment grounding conductor connection.
(b)
Grounded circuit conductor connection, if provided.
(c)
Ungrounded conductor connection, and that disconnection shall be in the
reverse order.
(3)
A caution notice shall be provided adjacent to the line connectors
indicating the plug connection shall be in the following order:
(a)
Equipment grounding conductor connectors.
(b)
Grounded circuit conductor connectors, if provided.
(c)
Ungrounded conductor connectors, and that disconnection shall be in the
reverse order.
530-23. Branch Circuits.
A branch circuit of any size supplying one or more receptacles shall be
permitted to supply stage set lighting loads.
C.
Dressing Rooms.
530-31. Dressing Rooms.
Fixed wiring in dressing rooms shall be installed in accordance with wiring
methods covered in Chapter 3. Wiring for portable dressing rooms shall be
approved.
D.
Viewing, Cutting, and Patching Tables
Table 400-5(B). Ampacity of Cables Type SC, SCE, PPE, G, and W.
[Based on
Ambient Temperature of 30º (86ºF). See Table 400-4.] Temperature Rating of
Cable
