17. 17
Color Temperature
Color Temperature is noted in
degrees Kelvin* or °K
3,000°K - Warm White
3,500°K - Neutral
4,100°K Cool White
* The Kelvin Scale is defined as Celsius plus 273.
18. 18
Color Temperature Definition
• the electromagnetic radiation emitted from an ideal black body
• 1,700 K Match flame
• 1,850 K Candle flame, sunset/sunrise
• 2,700–3,300 K Incandescent lamps
• 3,000 K Soft White compact fluorescent lamps
• 3,200 K Studio lamps, photofloods, etc.
• 3,350 K Studio "CP" light
• 4,100–4,150 K Moonlight
• 5,000 K Horizon daylight
• 5,000 K tubular fluorescent lamps or Cool White/Daylight CFL
• 5,500–6,000 K Vertical daylight, electronic flash
• 6,500 K Daylight, overcast
• 5,500–10,500 K LCD or CRT screen
• 15,000–27,000 K Clear blue poleward sky
19. 19
Typical Color Temperatures
Incandescent ……... 2,750 K – 3,400 K
Fluorescent ……….. 2,700 K – 6,500 K
Mercury vapor ….. 3,300 K – 6,000 K
Metal Halide ……… 3,000 K – 4,300 K
High Pressure
Sodium …………...... 1,900 K – 2,200 K
Induction …………… 3,000 K – 4,000 K
21. 21
Color Rendering Index (CRI)
Color Rendering Index is a scale
from 0-100 that indicates the
accuracy with which a lighting
source can reproduce colors. The
higher the CRI value the more
accurate the color reproduction.
22. 22
Color Rendering Index (CRI)
Typical high CRI values: 80 to 90
Typical good CRI values: 65 to 80
Typical poor CRI values: <65
Note: The CRI for standard Low Pressure
Sodium lamps is extremely poor.
27. 27
Rated Life of a Lamp
For non-HID lamps
(incandescent, fluorescent, etc.) the
test sample operating time is 3
hours.
For HID lamps (MV, MH, & HPS) the
test sample operating time is 10
hours.
30. 30
Light & Distance
The lighting level drops off as the
square of the distance.
E = I/d2
Where:
E = Illuminance (footcandles or lux)
I = Intensity of lighting in Candelas
D = Distance from the source
31. 31
Light & Distance
Therefore, even small changes in the
mounting height of a luminaire can
have a significant impact on the
lighting level.
36. 36
Lighting Levels
• Specific tasks to be performed
• Time required for each task
• Speed and accuracy
• Age of occupants
• Safety and security
• Aesthetics
• System operating cost
44. 44
Halogen Lamps
Advantages:
1. Higher efficacy than standard lamps
2. Better color rendering
3. Longer life (2,000 hours)
Disadvantages:
1. Same as standard incandescent
2. Higher price
46. 46
Fluorescent Lamps
Lamps are available it the following
configurations:
T-5 T-12 (being phased out)
T-8 T-17 (PG-17)
T-10
Note: In dual pin configurations, T-8, T-10, and T-12 lamps
have the same pin spacing. Therefore, they can be used in the
same fixture.
47. 47
Fluorescent Lamps
T-12 Lamps
Tubular lamp 12/8 of an inch, or 1.5", in
diameter.
This type lamp comes in a variety of
wattages and configurations.
Typical Lamp Wattages:
34W, 40W, 60W, and 95W
48. 48
Fluorescent Lamps
T-8 Lamps
Tubular lamp 8/8 of an inch, or 1.0", in
diameter. This type lamp comes in several
lengths and is typically used with
electronic ballasts.
Typical Lamp Wattages: 32W, 59W and
86W
2800 lumens (32 watt bulb)
49. 49
Fluorescent Lamps
T-5 Lamps
Tubular lamp 5/8 of an inch in diameter.
This type lamp comes in several lengths
and is typically used with electronic
ballasts.
Typical Lamp Wattages:
24W(21.6″), 39W(33.4″) , 54W(45.2″), and
80W(57.0″)
50. 50
Low Mercury Lamps
In 1980 a four-foot T-12 fluorescent
lamp typically contained approximately
100 mg of mercury.
By 2000 that value has
been cut by over 90%.
58. 58
Reflectors
• Reflectors allow the user to direct most of the
light downward toward surfaces of interest
instead of lighting the ceiling.
• Reduce electric consumption by reducing the
number of lamps required for desired light
output.
• 3 Types (Reflective Efficiency)
– Standard Aluminum Reflector (86%)
– Reflective White Paint (91%)
– Enhanced Specular Aluminum (95%)
60. 60
HID Lamp Characteristics
All HID lamps share certain physical and
operating characteristics.
– All HID lamps utilize an internal arc tube and
outer envelope construction.
– They all require a ballast for operation.
– All HID lamps require a warm-up period.
– They all require a cool-down period before they
can re-strike.
– A stroboscopic effect may occur prior to lamp
failure
62. 62
Mercury Vapor Lamps
Mercury vapor lamps produce a bluish-green
color light. Due to their lower efficacy and
poor color rendition they are seldom used in
new construction.
Interior applications are minimal. Most
current uses are for outdoor area/ parking
lot lighting.
65. 65
Metal Halide Lamps
All MH lamps offer a number of
advantages over MV lamps, including:
- Higher efficacy (~ 100 lumens/watt)
- A crisp clear white light
- Excellent color rendition (CRI 70 - 80)
Also, reduced wattage lamps are available for selected sizes of standard
MH lamps.
66. 66
Metal Halide Lamps
Disadvantages for MH lamps include:
- Shorter lamp life for equivalent sizes,
when compared to other HID sources
(6,000 to 16,000+ hours)
- Higher lamp cost
- Orientation sensitive
67. 67
Metal Halide Lamps
Disadvantages for MH lamps include:
- Color shift near the end of lamp life
- NEC 2005 requirements: The use of metal
halide lamps must be
- enclosed to provide contamination barrier
(Type S lamps) or
- used in a lamp holder that will only accept
ANSI Type O (shrouded) lamps
73. 73
HPS Lamps
High pressure sodium lamps have
been used extensively for both
interior and exterior applications.
Due to their high efficacy (~120
lumens per watt).
Since the mid 70’s HPS fixtures have
been used extensively for street
lighting.
74. 74
HPS Lamps
High pressure sodium lamps provide a
golden-yellowish color light. This is due
to the fact that they do not produce
light in the blue spectrum (450 - 490
nm). While not a concern in exterior
applications, some find the resulting
color unacceptable for interior
use, especially if color is a
consideration.
76. 76
HPS Lamps
In many applications high pressure
sodium lamps are being changed
to fluorescent. Often, a 460 Watt
HPS lamp can be replaced with a
210 Watt T-5 fluorescent fixture or
a 220 Watt T-8 fixture
78. 78
LPS Lamps
Low Pressure Sodium is not an HID
source. It is a gaseous discharge
type lamp, similar in operation to
fluorescent lamps.
79. 79
LPS Lamps
While very efficient, (producing
about 160 lumens/watt), LPS
lamps are a monochromatic light
source. They produce only one
color of light, a dirty yellow.
81. 81
LPS Color
Color reproduction is so poor that
under the Coloring Rendering Index
scale the CRI for low pressure
sodium is Negative.
82. 82
Induction Lamps
• Electromagnetic transformers create a field around a glass
tube containing a gas
• The high frequency ballast creates a flow of free electrons
which collide with mercury atoms and increase their energy
state
• When the mercury atoms return to their lower energy state
they emit ultraviolet radiation
• The UV radiation is converted to visible light as it passes
through a phosphor coating on the surface of the tube
83. 83
Induction Lamps
• Induction lamps are basically electrodeless fluorescent
lamps
• Without electrodes the life of the lamp can be extended to
100,000 hours
• Efficacy is 85 lumens/watt
• CRI is 85
112. 112
Fluorescent Exit Signs
Fluorescent signs typically utilize
one or two lamps.
More efficient that incandescent
with longer lamp life (6,000 -
10,000 hours).
113. 113
LED Exit Signs
In new or retrofit applications two
lamps are typically used.
Very efficient (4-8 W/fixture),
excellent lamp life
(20 years).
LED retrofit lamp
115. 115
Photoluminescent Exit Signs
No energy required, glow in the
dark (non-tritium) exit signs
Rated life 5 -25 years depending on
model
Should comply with
UL924 for exit signs
Courtesy of American Permalight
119. 119
Occupancy Sensors
Most sensors in commercial
applications utilize either passive
infrared (PIR) or ultrasonic
technology. There are hybrid
sensors employing both
technologies.
121. 121
Timeclocks
Timeclocks can be effectively
utilized for basic on/off operation
of lighting fixtures. By utilizing low
voltage relays, large numbers of
fixtures can be controlled by a
single timeclock, thereby making it
very cost effective.
122. 122
Timed Switches
Timed Switches are switches that
incorporate a timed function, to
ensure that the fixtures are turned
off after a preset interval of
time, typically one to two hours.
123. 123
Timed Switches
They are available in both standard
toggle switch and programmable
models.
Prior to the controlled fixtures being
turned off, these switches will provide a
warning; in the form of blinking lights or
an audible beeping sound (or both on
some models).
126. 126
Photocells
Photocells are low cost reliable
controls that utilize a photo-
sensitive element to control on/off
operation of a fixture or fixtures.
While primarily used in outdoor
applications they can also used in
building atriums.
128. 128
Lighting Control Panels
Today, control panels have become
very sophisticated, with control
capabilities far beyond basic on/off
operation, i.e. “smart panels”.
133. 133
Basic Principles of Lighting Energy Management
1. If you don’t need it, turn it off
- Employee Awareness, Sensors,
Timers, Photocells, Timed Switches,
Energy Management Systems, etc.
2. Proper maintenance
- Group cleaning and relamping
134. 134
Basic Principles of Lighting Energy Management
3. Enhanced lighting control
- Photocells and occupancy sensors
4. More efficient sources
- Electronically ballasted fluorescent fixtures,
- Compact fluorescents
- Induction lamps
- Light emitting diodes (LEDs)
138. 138
Case 2: Dairy Product Processor
Electric Rates: Usage: $.0400/kWh Demand: $0.0/kW
Operating Hours of Fixtures: 8,760 hours/yr
Background:
Portions of the production area are lit with (125) 2x4 T12 fixtures
(4 – 4’ T12 lamps with magnetic ballasts)
Power Rating: 144-watts
Annualized Maintenance Cost per fixture: $17.11
Recommendation:
Replace with (125) 2-lamp T8 fixtures with (1) parallel-wired
electronic ballast and reflectors.
Power Rating: 55-watts
Annualized Maintenance Cost per fixture: $6.63
139. 139
Savings:
Usage: 97,455 kWh/yr $3,898 / yr
Demand: 134 kW/yr $0 / yr
Maintenance: $1,310 / yr
Total Savings: $5,208 / yr
Implementation Cost: $11,100
TVA Rebate: $9,746
Simple Payback Period: 2.13 years (0.26 yrs)
Case 2: Dairy Product Processor
140. 140
Case 3: Automotive Components Manufacturer
Electric Rates: Usage: $.040/kWh Demand: $0.0/kW
Operating Hours of Fixtures: 8,760 hours/yr
Background:
(31) Exit fixtures are equipped with (2) 20-watt lamps each
Power Rating: 40-watts
Annualized Maintenance Cost per fixture: $25.81
Recommendation:
Replace with (31) LED exit fixtures, each with (2) 2-watt LED lamps
Power Rating: 4-watts
Annualized Maintenance Cost per fixture: $9.32
141. 141
Savings:
Usage: 9,776 kWh/yr $391 / yr
Demand: 13 kW/yr $0 / yr
Maintenance: $511 / yr
Total Savings: 902 / yr
Implementation Cost: $1,513
TVA Rebate: $978
Simple Payback Period: 1.68 years (0.59 yrs)
Case 3: Automotive Components Manufacturer
142. 142
Case 4: Auto Parts Manufacturer
Electric Rates: Usage: $.065/kWh Demand: $12.47/kW
Operating Hours of Fixtures: 8,736 hours/yr
Background:
There are (114) 400-watt metal halide fixtures throughout the facility
Power Rating: 450-watts/fixture
Annualized Maintenance Cost per fixture: $19.71
Recommendation:
Replace with (114) 220-watt T8 fluorescent fixtures
Power Rating: 220-watts
Annualized Maintenance Cost per fixture: $11.76
143. 143
Savings:
Usage: 229,058 kWh/yr $14,889 / yr
Demand: 314.6 kW/yr $3,924 / yr
Maintenance: $906 / yr
Total Savings: $19,719 / yr
Implementation Cost: $45,326
TVA Rebate: $22,906
Simple Payback Period: 2.30 years (1.14 yrs)
Case 4: Auto Parts Manufacturer
