Specifications

“Lighting Systems Made Easy” Page 26
JOULE
An energy/time measurement usually used for strobes. 1 watt at 1 second = 1 Joule.
LOAD
Power drawn by lighting (see watt and amp)
LUMEN
A measure of light output. The higher the lumen number, the more light emitted by the lamp.
MEMORY
The ability for a lighting controller, or console, to remember pre-programmed information.
Used to call up operator-programmed presets and scenes.
MIDI (acr.: MUSICAL INSTRUMENT DIGITAL INTERFACE)
Having been originally developed for the music industry. MIDI is finding increasing use for
lighting control purposes.
PARALLEL
Companion wiring mode for lamps, comparable to (but different from) series wiring. Every
lamp has its own + and – electrical power connections. If one lamp burns out the others will
stay alight.
PAR (acr.: PARABOLIC ALUMINIZED REFLECTOR)
The number indicated the size measured in pitches of 1/8” across the curved front of the lamp,
so a PAR 38 lamp is 38 x 1/8” across the front of the lamp.
PHASE CONTROL
The method normally used to dim a lamp, or number of lamps, using A.C. power. Unless
properly filtered at the dimmer packs, Phase Control may give rise to RFI (Radio Frequency
Interference), normally at its worst at around 25 to 70% of dimming and characterized by a
“buzzing” heard in the audio.
PLOT
Primarily a theatrical term for a number of predetermined lighting scenes that have been
arranged so they run in a particular order or sequence. The term is also used to denote a plan
or drawing that shows where lights are placed in a given venue, the types of instruments se-
lected and their wiring (Electrical Plot) and quantity.
POWER PACK (a.k.a. DIMMER PACK)
Handles high power loads and provides the electrical “muscle” for the controller. Usually
installed in a power room remote to minimize RFI.
PRESET(S)
A lighting term for a scene stored in memory for later use during a performance. Also used to
connote the faders on a lighting console.