by an amplifier into its rated load as determined under specified test conditions. This may exceed the manufacturer's rated output power for the same amplifier.
Mixer. Equipment used to combine and level match a multiplicity of electronic signals, such as from microphones, electronic instruments, and recorded audio.
Mixer-Amplifier. Equipment that combines the functions of a mixer and amplifier within a single enclosure.
Portable Equipment. Equipment fed with portable cords or cables intended to be moved from one place to another.
Powered Loudspeaker. Equipment that consists of a loudspeaker and amplifier within the same enclosure. Other signal processing may also be included.
Rated Load Impedance. The amplifier manufacturer's stated or marked speaker impedance into which an amplifier will deliver its rated output power; 2Q, 4Q, and 8Q are typical ratings.
Rated Output Power. The amplifier manufacturer's stated or marked output power capability into its rated load.
Rated Output Voltage. For audio amplifiers of the constant-voltage type, the nominal output voltage when the amplifier is delivering full rated power. Rated output voltage is used for determining approximate acoustic output in distributed speaker systems that typically employ impedance matching transformers. Typical ratings are 25 volts, 70.7 volts, and 100 volts.
Technical Power System. An electrical distribution system with grounding in accordance with 250.146(D), where the equipment grounding conductor is isolated from the premises grounded conductor except at a single grounded termination point within a branch- circuit panelboard, at the originating (main breaker) branch-circuit panelboard, or at the premises grounding electrode.
Temporary Equipment. Portable wiring and equipment intended for use with events of a transient or temporary nature where all equipment is presumed to be removed at the conclusion of the event.
640.3 Locations and Other Articles. Circuits and equipment shall comply with 640.3(A) through (L), as applicable.
(A) Spread of Fire or Products of Combustion. Section
300.21 shall apply.
(B) Ducts, Plenums, and Other Air-Handling Spaces.
See 300.22 for circuits and equipment installed in ducts
or plenums or other space used for environmental air.
FPN: NFPA 90A-2002, Standard for the Installation of Air
Conditioning and Ventilation Systems, Section
4.3.10.2.6.5, permits loudspeakers, loudspeaker
assemblies, and their accessories listed in accordance
with UL 2043-1996, Fire Test for Heat and Visible Smoke
Release for Discrete Products and Their Accessories
Installed in Air-Handling Spaces, to be installed in other
spaces used for environmental air (ceiling cavity
plenums).
(C) Cable Trays. Cable trays shall be used in accordance with Article 392.
FPN: See 725.154(C) for the use of Class 2, Class 3, and
Type PLTC cable in cable trays.
(D) Hazardous (Classified) Locations. Equipment used in hazardous (classified) locations shall comply with the ap plicable requirements of Chapter 5.
(E) Assembly Occupancies. Equipment used in assembly occupancies shall comply with Article 518.
(F) Theaters, Audience Areas of Motion Picture and Television Studios, and Similar Locations. Equipment used in theaters, audience areas of motion picture and
television studios, and similar locations shall comply with Article 520.
(G) Carnivals, Circuses, Fairs, and Similar Events.
Equipment used in carnivals, circuses, fairs, and similar events shall comply with Article 525.