Light It Right – Now You Try It!
LIGHT IT RIGHT
Now You Try It!
©1985-2008 RAB Lighting Inc.
Light It Right – Now You Try It!
SECTION ONE: Basics of Isofootcandle charts
Exercise 1: Refer to the chart above
A) What do the curves represent?
__________________________________________________________
__________________________________________________________
B) What do the blocks represent?
__________________________________________________________
__________________________________________________________
C) What are the charts at the bottom?
__________________________________________________________
__________________________________________________________
D) How much light is there 15’ in front of the fixture?
______________
E) How much light is there at 22’-6” in front of the fixture? ___________
©1985-2008 RAB Lighting Inc.
P. 1
Light It Right – Now You Try It!
SECTION ONE: Basics of Isofootcandle charts
(Using Multipliers)
To find the footcandle
value when changing
mounting height:
•
•
•
10’
10 X 2.3=
23
Find the multiplier
closest to the new
height
5 X 2.3=
11.5
Multiply the
footcandle values
shown by the
multiplier
3 X 2.3=
6.9
Each grid space is
now based on your
new mounting
height
.5 X 2.3=
1.1
1 X 2.3=
2.3
NEW
HEIGHT
EXAMPLE
Exercise 2: Fill in the blanks
Using the chart above, determine
the new footcandle values based
on an 8’ mounting height
8’ Mounting Height multiplier = ______
175w MH @ _____ Mounting Height
= 10fc x _____
__8_’ = __8_ ’ x
= 5fc x _____
= 3fc x _____
_____’ = ____ ’ x
= 1fc x _____
= .5fc x _____
_____’ = ____ ’ x
___’
___’
___’
©1985-2008 RAB Lighting Inc.
___’
P. 2
Light It Right – Now You Try It!
SECTION ONE: Basics of Isofootcandle charts
(Using Multipliers)
To find the footcandle
value when changing
lamp wattage or source:
70W
10 X .4=4
•
•
•
Find the multiplier
for the new wattage
or source
5 X .4= 2
3 X .4=1.2
Multiply the
footcandle values
by the multiplier
1 X .4=.4
.5 X .4=.2
The isofootcandle
chart is now based
on the new wattage
NEW
WATTAGE
EXAMPLE
Exercise 3: Fill in the blanks
100w MH multiplier = ______
Using the chart above,
determine the new footcandle
values based on a 100 WATT
Metal Halide Lamp
______w MH @ 15’ Mounting Height
= ____fc x _____
_____’ = ____ ’ x
= ____fc x _____
= ____fc x _____
_____’ = ____ ’ x
= ____fc x _____
_____’ = ____ ’ x
= ____fc x _____
___’
___’
___’
©1985-2008 RAB Lighting Inc.
___’
P. 3
Light It Right – Now You Try It!
SECTION ONE: Basics of Isofootcandle charts
To find the footcandle
value when changing
both the mounting height
and lamp wattage or
source:
(Using Multipliers)
10’
70W
10 x .6 x .4
= 2.4
•
•
Find the multipliers for
the new mounting height
and wattage or source
5 x .6 x .4 =
1.2
3 x .6 x .4=
.72
Multiply the footcandle
values by the multipliers
1 x .6 x .4=
.24
•
The isofootcandle chart
is now based on the new
mounting height AND
wattage
.5 x .6 x .4=
.12
NEW WATTAGE
NEW HEIGHT
EXAMPLE
Exercise 4: Fill in the blanks
25’ Mounting Height multiplier = ______
Using the chart above,
determine the new footcandle
values based on:
150w HPS multiplier = ______
25’ Mounting Height and
______w HPS @ ____’ Mtg. Height
150 WATT HPS Lamp
= ____fc x ____ x ____
_____’ = ____ ’ x
= ____fc x ____ x ____
= ____fc x ____ x ____
_____’ = ____ ’ x
= ____fc x ____ x ____
= ____fc x ____ x ____
_____’ = ____ ’ x
___’
___’
___’
©1985-2008 RAB Lighting Inc.
___’
P. 4
Light It Right – Now You Try It!
SECTION ONE: Basics of Isofootcandle charts
Exercise 5: Fill in the blanks
Using the chart above,
determine the new footcandle
values based on:
______w MH @ ______’ Mounting Height
15’ Mounting Height
___’
___’
©1985-2008 RAB Lighting Inc.
___’
___’
P. 5
Light It Right – Now You Try It!
SECTION ONE: Basics of Isofootcandle charts
Exercise 6: Fill in the blanks
Using the chart above, determine the
new footcandle values based on:
______w MH @ ______’ Mounting Height
8’ Mounting Height and
100 WATT metal halide Lamp
How much light is there now at
24’ in front of the fixture? ____
___’
___’
©1985-2008 RAB Lighting Inc.
___’
___’
P. 6
Light It Right – Now You Try It!
SECTION TWO: Fixture Comparisons
Exercise 1: Demonstrate the cutoff advantage of lower wattage at equal heights
Using the charts below, determine the new footcandle values based on: 20’ Mounting Height
Mounting
Height
Multiplier
10
6.3
15
2.8
20
1.6
25
1.0
30
0.7
______w MH @ ______’ Mounting Height
___’
___’
___’
______w MH @ ______’ Mounting Height
___’
___’
___’
___’
___’
Based on your results, approximately how far from each fixture is the .5fc value?
.5fc (WP3H250) = ______’
.5fc (WP2CH175) = ______’
In addition to lower wattage at = heights, list two other cutoff advantages:
1) _________________________________________________________________
2) _________________________________________________________________
©1985-2008 RAB Lighting Inc.
P. 7
Light It Right – Now You Try It!
SECTION TWO: Fixture Comparisons
Exercise 2: Control the forward throw
A cutoff style wallpack will limit the forward throw to 3 mounti ng heights
A full cutoff wallpack will limit the forward throw to 1.5 mounting heights
Refer to the charts above
How far away from the fixture is the .5
How far away from the fixture is the .5
footcandle level?
footcandle level?
______________
______________
What is the highest footcandle level on the
What is the highest footcandle level on the
chart?
chart?
___________________________
___________________________
How else could you reduce the forward
How else could you reduce the forward
throw?
throw?
___________________________
©1985-2008 RAB Lighting Inc.
___________________________
P. 8
Light It Right – Now You Try It!
SECTION TWO: Fixture Comparisons
Exercise 3: Control the forward throw
Determine the new footcandle values based on:
70W metal halide
Determine the new footcandle values based
on: 10’ Mounting Height
MTG HT MULTIPLIER
10.0
15
20.0
25
2.3
1.0
0.6
0.4
Watts
42
70
70PS
100
125PS
150PS
150
175
HPS
MH
CFL
0.4
0.7
1.1
1.8
0.6
1.0
1.3
1.6
1.4
1.5
How far away from the fixture is the .5
footcandle level? ____________________
How far away from the fixture is the .5
footcandle level? ____________________
What is the highest footcandle level on the
chart? _____________________________
What is the highest footcandle level on the
chart? _____________________________
How else could you reduce the forward throw ?
______________________________
How else could you reduce the forward throw ?
______________________________
©1985-2008 RAB Lighting Inc.
P. 9
Light It Right – Now You Try It!
SECTION TWO: Fixture Comparisons
Exercise 4
Refer to the charts above
A) How far away is the .5fc value from each fixture ?
B) Using a 30’ mounting height and 4:1 spacing / mounting height ratio,
How many of which fixture would you use to light an area of 50’ x 250’ ?
C) Using a 30’ mounting height and 4:1 spacing / mounting height ratio, How
many of which fixture would you use to light an area of 100’ x 350’ ?
©1985-2008 RAB Lighting Inc.
P. 10
Light It Right – Now You Try It!
©1985-2008 RAB Lighting Inc.
P. 11
Light It Right – Now You Try It!
SECTION THREE: Lighting Applications
Exercise 1
Mounting
Height Multiplier
10
6.3
15
2.8
20
1.6
25
1.0
30
0.7
Watts
200PS
250
250PS
320PS
350PS
400
400PS
Multiplier
HPS
MH
1.0
1.4
1.0
1.2
1.5
1.7
2.4
1.7
1.9
Refer to the charts above
At a 20’ mounting height, determine
which fixture and what wattage you
would use to limit light to .5fc at 50’
away?
How many fixtures would you use
to cover 240’ of length?
Use a 3:1 spacing to
mounting height ratio
©1985-2008 RAB Lighting Inc.
P. 12
Light It Right – Now You Try It!
SECTION THREE: Lighting Applications
Exercise 2 - SIGNS
•
Fixtures should be setback from and aimed up
approximately 2/3 the height of the vertical
surface
•
Fixtures should be horizontally spaced (center
to center) @ 1.5x the height of the vertical
surface
EXAMPLE
Refer to the guidelines above and determine the
quantity and location of fixtures for each exercise
©1985-2008 RAB Lighting Inc.
P. 13
Light It Right – Now You Try It!
SECTION THREE: Lighting Applications
Exercise 3: FLAGS
Flaglighting
• Use at least 2, preferably 3 lights in a triangle
• Set the fixtures away from the pole base 1/3 to 1/2 the height
of the pole
• Choose a lamp beam spread with the right diameter for the
flag size at its flying height
• Choose a lamp wattage that will supply a footcandle level
about 5 times brighter than the ambient level (10-15 fc for 2-3
fc residential areas and 20-25 fc for public flags in bright 4-5fc
areas)
• Try to shield the light source from view using hoods or visors
• If using less than three fixtures, delete the ones furthest from
view of those passing by
Setback = 1/3 – ½ H
Refer to the above guidelines
and determine the proper
setback for each example
©1985-2008 RAB Lighting Inc.
P. 14
Light It Right – Now You Try It!
SECTION THREE: Lighting Applications
Exercise 4: FLOODS
Floodlighting
• Recommended mounting height is one-half the distance across
the area to be lit
• Recommended horizontal spacing for poles is four times the
mounting height from the adjacent pole
• Recommended vertical aiming is two-thirds of the distance
across the area to be lit, and at least 30 degrees below horizon
Refer to the isofootcandle
chart shown at right.
Indicate the quantity and
location of FZH400 fixtures
would you use to light a 75’
x 200’ area.
75’
200’
©1985-2008 RAB Lighting Inc.
P. 15
Light It Right – Now You Try It!
SECTION FOUR: Online Layouts
Navigate your way to:
www.rabweb.com
©1985-2008 RAB Lighting Inc.
P. 16
Light It Right – Now You Try It!
SECTION FOUR: www.rabweb.com
Exercise 1
Step 1.
Search for an FZH175QT
Step 2.
Click the link for an EZ Layout
• Set the
mounting
height to 12’
• Tilt the Fixture
30 degrees
below horizon
For an FZH175QT at a 12’ mounting height and aimed 30 degrees below horizon:
How far away from the fixture is the .5 fc value? ________
©1985-2008 RAB Lighting Inc.
P. 17
Light It Right – Now You Try It!
SECTION FOUR: www.rabweb.com
Exercise 2
Determine the best type, wattage, and quantity of fixtures to
light the back of this commercial building.
The fixtures will be mounted at 15’ AFG
No more than .5 fc of light is permitted beyond 50’ from the
building
Create an online layout to display your results
Refer to the EZ guidelines on page 10
50’
©1985-2008 RAB Lighting Inc.
P. 18
Light It Right – Now You Try It!
SECTION FOUR: www.rabweb.com
Exercise 3
Determine the best type, wattage, and quantity of fixtures to
light the parking lot shown below
The lot must be uniformly lit to .5 fc
Create an online layout to display your results
Refer to the floodlighting rules of thumb on
page 14 and the EZ guidelines on page 10
Poles located on this side
Poles located on this side
©1985-2008 RAB Lighting Inc.
P. 19
Light It Right – Now You Try It!
SECTION ONE: Basics of Isofootcandle charts
A) What do the curves represent?
The curves (contour lines) represent the general shape of the light
The curves also define areas of equal illuminance
Each curve represents a different footcandle value
B) What do the blocks represent?
Each block is a distance from the fixture.
This distance is equal to the mounting height of the fixture.
On this chart, each mounting height is 15 feet.
C) What are the charts at the bottom?
The charts below the isofootcandle graphic contain multipliers
used for determining corrected footcandle values when changing
lamp type, wattage or mounting height
D) How much light is there 15’ in front of the fixture?
On this chart, 15’ Represents 1 mounting height. There is
approximately 6-7 footcandles of light at this distance
E) How much light is there at 22’-6” in front of the fixture?
On this chart, 22’-6” = 1.5 mounting heights. At this distance, there
is approximately 3 footcandles of illuminance
©1985-2008 RAB Lighting Inc.
P. 20
ANSWER SECTION
Exercise 1: Refer to the chart above
Light It Right – Now You Try It!
SECTION ONE: Basics of Isofootcandle charts
Using Multipliers
To find the footcandle
value when changing
mounting height:
•
•
10 X
2.3= 23
Find the multiplier
closest to the new
height
5 X 2.3=
11.5
Multiply the
footcandle values
shown by the
multiplier
3 X 2.3=
6.9
1 X 2.3=
2.3
Each grid space is
now based on your
new mounting
height
ANSWER SECTION
•
10’
.5 X 2.3=
1.1
NEW
HEIGHT
EXAMPLE
Exercise 2: Fill in the blanks
8’ Mounting Height multiplier = 3.5
Using the chart above, determine
the new footcandle values based
on an 8’ mounting height
175w MH @ 8’ Mounting Height
35
= 10fc x 3.5
17.5
= 5fc x 3.5
_8___’ = __8_ ’ x
10.5
= 3fc x 3.5
_16__’ = __8_ ’ x
_24__’ = __8_ ’ x
_16’
_8’
3.5
= 1fc x 3.5
1.75
= .5fc x 3.5
8_’
©1985-2008 RAB Lighting Inc.
_16’
P. 21
Light It Right – Now You Try It!
SECTION ONE: Basics of Isofootcandle charts
Using Multipliers
To find the footcandle
value when changing
lamp wattage or source:
70W
10 X .4= 4
•
•
5 X .4= 2
3 X .4=
1.2
Multiply the
footcandle values
by the multiplier
1 X .4= .4
.5 X .4= .2
The isofootcandle
chart is now based
on the new wattage
NEW
WATTAGE
EXAMPLE
Exercise 3: Fill in the blanks
Using the chart above,
determine the new footcandle
values based on a 100 WATT
Metal Halide Lamp
ANSWER SECTION
•
Find the multiplier
for the new wattage
or source
100w MH multiplier = .7
100w MH @ 15’ Mounting Height
= 10 fc x .7
7 fc
15’ = 15 ’ x
= 5 fc x .7
3.5 fc
2.1 fc
= 3 fc x .7
.7 fc
= 1 fc x .7
.35 fc
= .5 fc x .7
30’ = 15 ’ x
45’ = 15 ’ x
30’
15’
©1985-2008 RAB Lighting Inc.
15’
30’
P. 22
Light It Right – Now You Try It!
SECTION ONE: Basics of Isofootcandle charts
(Using Multipliers)
To find the footcandle
value when changing
both the mounting height
and lamp wattage or
source:
10’
70W
•
•
•
10 X 2.3=
23
Find the multipliers for
the new mounting height
and wattage or source
5 X 2.3=
11.5
3 X 2.3=
6.9
Multiply the footcandle
values by the multipliers
1 X 2.3=
2.3
.5 X 2.3=
1.1
NEW WATTAGE
NEW HEIGHT
EXAMPLE
Exercise 4: Fill in the blanks
25’ Mounting Height multiplier =
.4
Using the chart above,
determine the new footcandle
values based on:
25’ Mounting Height and
ANSWER SECTION
The isofootcandle chart
is now based on the new
mounting height AND
wattage
150w HPS multiplier = 1.2
150 w HPS @ 25’ Mtg. Height
150 WATT HPS Lamp
4.8fc
= 10 fc x .4 x 1.2
2.4fc
= 5 fc x .4 x 1.2
1.4fc
= 3 fc x .4 x 1.2
.48fc
= 1 fc x .4 x 1.2
.24 fc
= .5 fc x .4 x 1.2
25’ = 25 ’ x
50’ = 25 ’ x
75’ = 25 ’ x
50’
25’
25’
©1985-2008 RAB Lighting Inc.
50’
P. 23
Light It Right – Now You Try It!
SECTION ONE: Basics of Isofootcandle charts
ANSWER SECTION
Exercise 5: Fill in the blanks
Using the chart above,
determine the new footcandle
values based on:
15’ Mounting Height multiplier = 1.8
175w MH @ 15’ Mounting Height
15’ Mounting Height
15’
30’
45’
30’
___’
9 fc
= 5 fc x 1.8
5.4 fc
= 3 fc x 1.8
1.8 fc
= 1 fc x 1.8
.9 fc
= .5 fc x 1.8
.54 fc
= .3 fc x 1.8
15’
___’
©1985-2008 RAB Lighting Inc.
15’
___’
30’
___’
P. 24
Light It Right – Now You Try It!
SECTION ONE: Basics of Isofootcandle charts
ANSWER SECTION
8’ Mounting Height multiplier = 6.3
Exercise 6
100w MH multiplier = .7
Using the chart above, determine the
new footcandle values based on:
100w MH @ 8’ Mtg. Height
8’ Mounting Height and
100 WATT metal halide Lamp
8’
16’
24’
How much light is there now at
24’ in front of the fixture? 1fc +/-
16’
___’
22 fc
= 5 fc x 6.3 x .7
13 fc
= 3 fc x 6.3 x .7
4.4 fc
= 1 fc x 6.3 x .7
2.2 fc
= .5 fc x 6.3 x .7
1.3 fc
= .3 fc x 6.3 x .7
8’
___’
©1985-2008 RAB Lighting Inc.
8’
___’
16’
___’
P. 25
Light It Right – Now You Try It!
SECTION TWO: Fixture Comparisons
Exercise 1: Demonstrate the cutoff advantage of lower wattage at equal heights
Using the charts below , determine the new footcandle values based on: 20’ Mounting Height
ANSWER SECTION
Mounting
Height
Multiplier
10
6.3
15
2.8
20
1.6
25
1.0
30
0.7
250 w MH @ 20’ Mounting Height
20’
175 w MH @ 20’ Mounting Height
6 fc
20’
4.8 fc
3.2 fc
1.6 fc
40’
3 fc
1.8 fc
40’
.8 fc
60’
.6 fc
60’
.4 fc
40’
20’
20’ 40’
.3 fc
40’
20’
20’
40’
Based on your results, approximately how far from each fixture is the .5fc value?
.5fc (WP3H250) = 50’
.5fc (WP2CH175) = 50’
In addition to lower wattage at = heights, list two other cutoff advantages:
1)
Reduce glare / light pollution
2)
Smaller fixture size
©1985-2008 RAB Lighting Inc.
P. 26
Light It Right – Now You Try It!
SECTION TWO: Fixture Comparisons
Exercise 2: Control the forward throw
A cutoff style wallpack will limit the forward throw to 3 mounti ng heights
A full cutoff wallpack will limit the forward throw to 1.5 mounting heights
How far away from the fixture is the .5
How far away from the fixture is the .5
footcandle level?
footcandle level?
43’ +/-
22’- 6” +/-
What is the highest footcandle level on the
What is the highest footcandle level on the
chart?
chart?
10 fc
ANSWER SECTION
Refer to the charts above
10 fc
How else could you reduce the forward
throw?
How else could you reduce the forward
throw?
Use a Full Cutoff fixture
Use a lower mounting height
Use a lower mounting height
Use a lower wattage lamp
Use a lower wattage lamp
Use a cutoff strip
©1985-2008 RAB Lighting Inc.
P. 27
Light It Right – Now You Try It!
SECTION TWO: Fixture Comparisons
Exercise 3: Control the forward throw
Determine the new footcandle values based on:
70W metal halide
Determine the new footcandle values based
on: 10’ MTG. HT
Watts
42
70
70PS
100
125PS
150PS
150
175
HPS
ANSWER SECTION
MTG HT MULTIPLIER
10.0
2.3
15
1.0
20.0
0.6
25
0.4
MH CFL
0.4
0.7
1.1
1.8
0.6
1.0
1.3
1.6
1.4
1.5
4 fc
15’
23 fc
2 fc
10’
1.2 f c
30’
.4 f c
45’
11.5 f c
6.9 f c
2.3 f c
1.1 f c
20’
.2 f c
15’
20’ 10’
15’
10’
20’
How far away from the fixture is the .5
footcandle level? 30’ +/-
How far away from the fixture is the .5
footcandle level? 15’ +/-
What is the highest footcandle level on the
chart? 4 fc
What is the highest footcandle level on the
chart? 23 fc
How else could you reduce the forward throw ?
Use a lower mounting height
Use a cutoff strip
How else could you reduce the forward throw ?
Use a lower wattage lamp
©1985-2008 RAB Lighting Inc.
P. 28
Light It Right – Now You Try It!
SECTION TWO: Fixture Comparisons
Exercise 4
ANSWER SECTION
Refer to the charts above
A) How far away is the .5fc value from each fixture ?
.5 fc (Floodzilla) = 60’
.5 fc (Megaflood) = 80’
B) Using a 30’ mounting height and 4:1 spacing / mounting height ratio,
How many of which fixture would you use to light an area of 50’ x 250’ ?
250’
(2) Floodzilla
65’
120’
65’
C) Using a 30’ mounting height and 4:1 spacing / mounting height ratio, How
many of which fixture would you use to light an area of 100’ x 350’ ?
350’
(3) Megaflood
55’
120’
©1985-2008 RAB Lighting Inc.
120’
55’
P. 29
Light It Right – Now You Try It!
SECTION THREE: Lighting Applications
Exercise 1
Watts
200PS
250
250PS
320PS
350PS
400
400PS
Multiplier
HPS MH
1.0
1.4
1.0
1.2
1.5
1.7
2.4
1.7
1.9
Refer to the charts above
At a 20’ mounting height, determine
which fixture and what wattage you
would use to limit light to .5fc at 50’
away?
At a 20’ Mounting Height BOTH
fixtures will produce .5 fc or less
at 50’ from the fixture but the
WP2C 175 will use less energy
60’
60’
60’
60’
How many fixtures would you use
to cover 240’ of length?
Use a 3:1 spacing to
mounting height ratio
You could use 4 or 5 fixtures
to cover the 240’
©1985-2008 RAB Lighting Inc.
P. 30
ANSWER SECTION
Mounting
Height Multiplier
10
6.3
15
2.8
20
1.6
25
1.0
30
0.7
Light It Right – Now You Try It!
SECTION THREE: Lighting Applications
Exercise 2: SIGNS
•
Fixtures should be setback from and aimed up
approximately 2/3 the height of the vertical
surface
•
Fixtures should be horizontally spaced (center
to center) @ 1.5x the height of the vertical
surface
EXAMPLE
Refer to the guidelines above and determine the
quantity and location of fixtures for each exercise
ANSWER SECTION
8’
18’
5.3’
12’
6.6’
15’
15’
©1985-2008 RAB Lighting Inc.
P. 31
Light It Right – Now You Try It!
SECTION THREE: Lighting Applications
Exercise 3: FLAGS
Flaglighting
Setback = 1/3 – ½ H
Refer to the above guidelines
and determine the proper
setback for each example
ANSWER SECTION
Use at least 2, preferably 3 lights in a triangle
Set the fixtures away from the pole base 1/3 to 1/2 the height of
the pole
Choose a lamp beam spread with the right diameter for the flag
size at its flying height
Choose a lamp wattage that will supply a footcandle level about
5 times brighter than the ambient level (10-15 fc for 2-3 fc
residential areas and 20-25 fc for public flags in bright 4-5fc
areas)
Try to shield the light source from view using hoods or visors
If using less than three fixtures, delete the ones furthest from
view of those passing by
10’ - 15’
8.3’ - 12.5’
©1985-2008 RAB Lighting Inc.
P. 32
Light It Right – Now You Try It!
SECTION THREE: Lighting Applications
Exercise 4 - FLOODS
Floodlighting
Recommended mounting height is one-half the distance across the
area to be lit
Recommended horizontal spacing for poles is four times the
mounting height from the adjacent pole
Recommended vertical aiming is two-thirds of the distance across
the area to be lit, and at least 30 degrees below horizon
ANSWER SECTION
Refer to the isofootcandle
chart shown at right.
Indicate the quantity and
location of FZH400 fixtures
would you use to light a 75’
x 200’ area.
Based on a 30’
pole, You could
use 2 or 3 fixtures
200’
120’
40’
75’
40’
©1985-2008 RAB Lighting Inc.
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Light It Right – Now You Try It!
SECTION FOUR: www.rabweb.com
Exercise 1
Step 1.
Search for an FZH175QT
Step 2.
Click the link for an EZ Layout
• Tilt the Fixture
30 degrees
below horizon
ANSWER SECTION
• Set the
mounting
height to 12’
For an FZH175QT at a 12’ mounting height and aimed 30 degrees below horizon:
How far away from the fixture is
the .5 fc value? 34’ +/-
©1985-2008 RAB Lighting Inc.
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Light It Right – Now You Try It!
SECTION FOUR: www.rabweb.com
Exercise 2
Determine the best type, wattage, and quantity of fixtures to
light the back of this commercial building.
The fixtures will be mounted at 15’ AFG
No more than .5 fc of light is permitted beyond 50’ from the
building
Create an online layout to display your results
Refer to the EZ guidelines on page 10
ANSWER SECTION
WP2CH175QT
15’
45’
45’
15’
50’
©1985-2008 RAB Lighting Inc.
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Light It Right – Now You Try It!
SECTION FOUR: www.rabweb.com
Exercise 3
Determine the best type, wattage, and quantity of fixtures to
light the parking lot shown below
The lot must be uniformly lit to .5 fc
Create an online layout to display your results
Refer to the floodlighting rules of thumb on
page 14 and the EZ guidelines on page 10
ANSWER SECTION
MEGH250SFPSQ
30’ mounting height
-60,60,30
40’
60,60,30
120’
40’
120’
-60,-60,30
©1985-2008 RAB Lighting Inc.
40’
40’
60,-60,30
P. 36