bbbd 2011 efficient lighting fundamentals...color rendering a scale of the effect of a light source...
TRANSCRIPT
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Efficiency Vermont is a Registered Provider with The American
Institute of Architects Continuing Education Systems
(AIA/CES). Credit(s) earned on completion of this program will
be reported to AIA/CES for AIA members. Certificates of
Completion for both AIA members and non-AIA members are
available upon request.
This program is registered with AIA/CES for continuing
professional education. As such, it does not include content that
may be deemed or construed to be an approval or endorsement
by the AIA of any material of construction or any method or
manner of handling, using, distributing, or dealing in any material
or product.
Questions related to specific materials, methods, and services
will be addressed at the conclusion of this presentation.
Learning ObjectivesLearning Objectives
By the end of this program, participants will be able to:
• Understand key techniques & common terminology of energy-efficient lighting
• Gain knowledge that can strengthen your communications with lighting
designers, suppliers, and manufacturers
• Increase your understanding of lighting decisions on your projects
• Understand basic lighting terminology such as lumens, footcandles, color
temperature, color rendering, etc.
• Understand how to apply lighting terminology to the selection of new light
sources and fixtures.
• Understand how lighting terminology is critical to the evaluation of new energy
efficient lighting sources and fixtures.
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In order to maintain high-quality learning experiences, please
access the evaluation for this course by logging into CES
Discovery and clicking on the Course Evaluation link on the
left side of the page.
Course EvaluationsCourse Evaluations
Lighting TerminologyLighting Terminology
� Lumens
� Footcandles
� Illuminance
� Luminance
� Efficacy
� Color Temperature
� Color Rendering
Quantity of Light Appearance of Light
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Lighting TerminologyLighting Terminology
Lumen
A unit of light flow, or luminous flux. The lumen
rating of a lamp is a measure of the total light
output of the lamp.
The amount of light generated by a light source, at
the source.
Glossary definitions as defined by Architectural Lighting Magazine 2008.
Lighting TerminologyLighting Terminology
Footcandle (FC)
The English measurement of the illuminance (or
light level) on a surface. One footcandle is equal to
one lumen per square foot.
The amount of illumination measured (with a light
meter) on a vertical or horizontal surface…
We do not “see” footcandles…
Glossary definitions as defined by Architectural Lighting Magazine 2008.
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Lighting TerminologyLighting Terminology
Illuminance
A photometric term that quantifies light incident on
a surface or plane. Illuminance is commonly called
light level. It is expressed as lumens per square
foot (footcandles) or lumens per square meter (lux).
The term for the quantity of illumination that a light
meter measures (footcandles).
Glossary definitions as defined by Architectural Lighting Magazine 2008.
Lighting TerminologyLighting Terminology
Luminance
A photometric term that quantifies brightness of a
light source or of an illuminated surface that reflects
light. It is expressed as footlamberts (English units)
or candelas per square meter (Metric units).
The term for what we actually see, which is
reflected illumination off of a surface.
Glossary definitions as defined by Architectural Lighting Magazine 2008.
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LUMENSLUMENSLUMENSLUMENS
ILLUMINANCEILLUMINANCEILLUMINANCEILLUMINANCE(FOOTCANDLES)(FOOTCANDLES)(FOOTCANDLES)(FOOTCANDLES)
LUMINANCELUMINANCELUMINANCELUMINANCE(REFLECTED LIGHT)(REFLECTED LIGHT)(REFLECTED LIGHT)(REFLECTED LIGHT)
Lighting TerminologyLighting Terminology
Efficacy
A metric used to compare light output to energy
consumption. Efficacy is measured in lumens per
watt. Efficacy is similar to efficiency, but expressed
in dissimilar units. For example, if a 100 watt light
source produces 9000 lumens, then the efficacy is
90 lumens per watt.
Lumens per watt.
Glossary definitions as defined by Architectural Lighting Magazine 2008.
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Lighting TerminologyLighting Terminology
Color Temperature
The color temperature is a specification of the color
appearance of a light source, relating to the color of
a reference source heated to a particular
temperature, measured by the thermal unit Kelvin.
The measurement can also be described as the
“warmth” or coolness” of a light source.
The outward appearance of the color of a light
source (i.e. warm or cool).
Glossary definitions as defined by Architectural Lighting Magazine 2008.
2700 K
2900 K
3000 K
3500 K
4100 K
6000 K
4200 K
INCANDESCENT
3000K FLUORESCENT
3500K FLUORESCENT
4100K FLUORESCENT
COOL WHITE
NOON DAYLIGHT
LOW VOLT HALOGEN
WARM
COOL
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Lighting TerminologyLighting Terminology
Color Rendering
A scale of the effect of a light source on the color
appearance of an object compared to its color
appearance under a reference light source.
Expressed on a scale of 1 to 100, where 100
indicates no color shift. A low CRI rating suggests
that the colors of objects will appear unnatural
under that particular light source.
The ability of a light source to render colors in
comparison to other light sources of a similar color
temperature.
Glossary definitions as defined by Architectural Lighting Magazine 2008.
Spectral Power DistributionSpectral Power Distribution
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Determining FactorsDetermining Factors
•Color Temperature
•Color Rendering
•Color Changing
•Light Output
(actual)
•Lumen Output
•Efficacy
•Distribution
•Dimmability
•Heat Production
•Fixture Compatibility
•UV Transmittance
•Code Compliance
•Energy Efficiency
•Accessorization
•Soft / Hard Edge
•Effect on People
•Initial Cost
•Operating Cost
•Replacement Cost
•Ease of
Maintenance
•Availability
•Lamp Life
•Physical Size
•Physical
Appearance
Other Factors…Other Factors…
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Other Factors…Other Factors…
Other Factors…Other Factors…
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Other Factors…Other Factors…
Naming a Light Source Naming a Light Source
(incandescent)(incandescent)
WATTS
100
40
60
50
75
50
SHAPE
A
A
G
PAR
PAR
MR
SIZE
19
15
30
20
30
16
ATTRIBUTES
IF
CL
WH
NFL25
NSP15
FL35
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Naming a Light Source Naming a Light Source
(fluorescent)(fluorescent)
WATTS
F017
F17
F032
F32
CF32
PL-T32
SHAPE
T
T
DT
SIZE
8
8
ATTRIBUTES
830
SPX30
835
SPX35
E/IN/827
827/X/4P
Lamp Data ComparisonLamp Data Comparison
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Lamp Data ComparisonLamp Data Comparison
Inverse Square Law
FC = CBCP / Distance Squared
50PAR30/HAL/NFL25
FC = 2300 / 36
FC = 63.8
50PAR30/CAP/IR/NFL25
FC = 2900 / 36
FC = 80.5
50PAR30/HAL/FL40
FC = 1300 / 36
FC = 36.1
50PAR30/CAP/IR/FL40
FC = 1600 / 36
FC = 44.4
Lamp Data ComparisonLamp Data Comparison
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Lamp Data ComparisonLamp Data Comparison
Light Source DistributionLight Source Distribution
DirectDirectDirectDirect IndirectIndirectIndirectIndirect Indirect / Indirect / Indirect / Indirect /
DirectDirectDirectDirect
DiffuseDiffuseDiffuseDiffuse
(general)(general)(general)(general)
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Layers of LightLayers of Light
� General (ambient)
� Task
� Accent
� Sparkle