Cut Sheet

instant-start lamp
A class of fluorescent lamps which do not
require filament preheating and can start instantly.
Lutron dimming ballasts cannot be used with
instant-start lamps.
intensity
The brightness of a lamp as a percentage of
maximum brightness (e.g., 66% intensity describes
a lamp dimmed to 2/3 of its maximum brightness).
kilowatt hour (KWH)
A unit of energy equal to one kilowatt of power
expended for one hour.
lamp
A device for producing light (such as a bulb or tube).
LED driver
Auxiliary device(s) needed to operate and vary
the intensity of light output from LED lamp
source(s) by regulating the voltage and current
powering thesource. There are both dimming
and non-dimming types.
line voltage
The voltage between the lines of a supplying
powersystem.
load
The device which a dimmer is controlling (e.g.,
incandescent lamp, ceiling fan, fluorescent lamp).
low-end trim
Adjustable setting on a dimmer that establishes its
minimum output, therefore establishing minimum
light level.
lumen
The quantity of light that is emitted by a lamp, used
in reference to efficacy (lumens per watt).
luminance
Describes the light emitted or reflected from a
source or object in a particular direction. Luminance
produces the sensation of brightness and is
measured in candelas per square foot (or square
meter) of a source or object surface area in the
direction of viewing.
luminous efficacy
The ratio of light emitted to the power required for a
light source or luminaire. Commonly used to measure
energy efficiency, it is the lumens per watt from a light
source (amount of light per watt of power).
lux
1 lux = 1 lumen per square meter.
multi-location dimming
A technology that allows full-range dimming from all
locations in 3-way and 4-way circuits. Multi-location
dimmers can be used with companion dimmers for
full dimming control of the lights from 4 or
more locations.
phase control
A common method of dimming that removes part of
the line cycle, therefore reducing the RMS voltage.
power factor
Ratio of the average power delivered to the lamp
ballast system to the product of voltage and current
(the ratio of the average power to the VA). This shows
how effectively available power is being used.
radio frequency interference (RFI)
Electrical noise that may be picked up by sensitive
audio and radio equipment. Lutron builds filters into
every control and ballast to reduce this noise. Also
called electromagnetic interference (EMI). See filter.
rapid-start lamp
A class of fluorescent lamps having filaments which
must be constantly heated by an external circuit.
source
Refers to the type of lamp, (e.g., fluorescent,
incandescent, low voltage, HID, etc.).
Power Factor = Input power
Line voltage x line current
Ballast factor
RSE =
Ballast input power
x
Total rated
lamp power
relative system efficacy (RSE)
Relative system efficacy is a metric used to rank
ballast and lamp efficacy. It is used almost exclusively
to describe dimming ballast efficacy and uses
lamp rated efficacy to normalize Ballast Efficacy
Factor(BEF).
square law dimming
Dimming with a direct correlation between the
position of the slider and the perceived light level
(e.g., if the slider is halfway down the travel, the
perceived light level is 50%). With Square Law
Dimming, gradual movement of the linear slider
results in a proportional change in the perceived
light level–allowing for easy, precise adjustment of
the light level setting.
T4
A compact fluorescent lamp which has a diameter
of 1/2" (12.7 mm).
T5
A fluorescent lamp which has a diameter
of 5/8" (15.9 mm).
T8
A fluorescent lamp which has a diameter
of 1" (25.4 mm).
T5 HO
A fluorescent lamp which has a diameter of 5/8”
(15.9 mm) and delivers high lumen output.
T5 twin-tube
A fluorescent lamp which has a diameter of 5/8”
(15.9 mm) and is bent in a U-shape.
total harmonic distortion (THD)
The total amount of current at frequencies other than
60 Hz (the main frequency), expressed as a percent
of the 60 Hz current. No power is delivered to the
load by current at these other frequencies.
UL listed
Indicates that the product has been evaluated and
undergoes continual assessment by Underwriters
Laboratories Inc. to comply with safety standards
established by Underwriters Laboratories Inc.
3-way dimming
3-Way dimming control (as opposed to single-
pole or multi-location control) allows dimming from
one location only (using a 3-way dimmer) and on/
off switching from a second location (using a
3-wayswitch or companion/accessory dimmer).
For a more detailed glossary of terms, go to www.lutron.com/glossaryofterms.For a more detailed glossary of terms, go to www.lutron.com/glossaryofterms.
Appendix |Appendix |
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