CF-Deforest SC-CS 871130Form 252-A 4-76
GUARD-LITE RECORD
Customer'5 Name Account Number
Service is used for
Pole Installation: Number of /
Existing ~ Guard-Lite Units
Remarks:
Form 252-A 4-76 TEXAS POWER & LIGHT COMPANY
AGREEMENT FOR GUARD-LITE SERVICE -- NEW INSTALLATION
Ag ...... t dated /J-_~)~)'~3") bet ....Texas P ....& Light Company
(Company) and ~7',y ~" C~PP~L~ (customer)
1. Company agrees to install, own and maintain ~ outdoor i;,g,,.~,~ ;;~:;ts of
approximately 8,000 lumens each on Company poles now installed or to be installed
hereunder at or near ~-~3P~L~L~- '-"T')~ Texas; to
cause said lights to burn from dusk to dawn; and to maintain all fixtures and/or
replace lamps during regular daytime working hours as soon as practical following
notification from customer that such maintenance is required.
2. Customer agrees to take and pay for such lighting service on Company's established
Rate Schedule G L, which shatl be subject to change, from time to time, by
regulatory authorities having jurisdiction and under the terms of this agreement.
or upon such earlier date as Customer shall have begun to take service, and shall
continue in force for two (2) years, and t~ereafter from year to year unless
terminated by either party by written notice gi~/en not less than 3~days prior to any
expiration date. In the event the Guard-Lite~(s)lis disconnectel~(:~.t, a customer's
request prior to the end of the two year term,~u~omer will be ~l~G~red to pay an
amount equal to the Guard*Lite rate times the I~pber of months~l~n~ainin9 in the
original contract period and any deposit will De a d to that arno.
Manager Custo~erJ ~
D
ROADWAY LIGHTING CALCULATIONS
Once you know the desired level of illumination (or the
minimum level recommended from Section C), the next
question becomes--How far apart do I put the poles to
get this level of illumination?
Keep in mind that level of illumination values are averaqq
values and that usually calculations are based on maintained
figures with the lamp at its lowest output and luminaire in
its dirtiest condi.tion.
There are also several ways to place poles along a roadway.
Here are some of the more frequently used methods.
ONE SIDE - POLE PLACEMENT
~- spaging -~
Use 1 luminaire in formula
MEDIAN STRIP-POLE PLACEMENT
~-- spacin~
Use 2 luminaires in formula
STAGGERED - POLE PLACEMENT
~-Spa cing ~
Use 1 luminaire in formula
OPPOSITE - POLE PLACEMENT
~ spacing~
Use 2 luminaires in formula
Illustration ~11
Klm Lighting, Inc. D 1
The "spacing between poles" is determined by formula:
Spacing
Between =
Poles
Roadway Liq~tinq - Basic Formula
Number of
Luminaires
In-Line
Across the
Street At
One Point. Initial
See Illus- Horizontal
tration ~11 x Lamp Lumens
Average Maintained
Illumination Desired
in Footcandles
Coefficient
of
x Utilization x
Recommended
Light Loss
Factor
x Width
of
Roadway
The "number of luminaires in-line across the street at one point"
depends on the number of fixtures on each pole and the pole
placement. (See Illustration ~11)
The following table will give you values for "Initial Horizontal
Lumens" and Recommended Light Loss Factors" depending on lamp
used. Check the Ecology catalog for the proper coefficient of
Utilization.
kumenm
175 Watt Mercury Vapor - Deluxe White .7,750 0.74
250 Watt Mercury Vapor - Deluxe White 11,500 0.74
400 Watt Mercury Vapor - Deluxe White 21,500 ~ 0.71
400 Watt Metallic Halide - Clear 30.000 ~ ~ 0.70
~250 Watt Hiqh Pressure Sodium~ 25,500'- ~ ~ 0.80
~ ~ 0.81
400 Watt Hiqh Pressure Sodium ,47,000
100.0 Watt Mercury Vapor - clear ...54,500 0.76
1000 Watt Mercury Vapor -DelUxe White~ 60,000
1000 Watt Metallic Halide - Clear 95.,.000 0..78
!000 Wa.t.t. Hiqh Pressure Sodium 130~000 0.83
- Klm Liahtlng, Inc.
EXAMPLE:
"One Side" pole placement
One luminaire on each pole
Mounting Height - 30'
Width of Roadway - 50'
400 Watt metallic halide lamp -
30,000 lumens (Table Pg. D-2)
Average maintained illumination
desired - 2.0 footcandles
Spacing
Between = 1 x 30,000 x 0.41' x 0.70 = 86'
Poles 2.0 x 50
To determine the coefficient of utilization, follow steps 1 and 2.
House t Street
Side ~ I ~ Side
~----Width of Roadway
50'
STEP
Read
0.41
C.U.
And
Use
In
Formula
i ---~ r street side--
........ ~~~~'~/ I
/,
,~,
/
I
/
/ . house side
0.6
0.5
0.4
0.3
~0.~
0.~
! ' '1 ~'
~1~ 0 I 2 3 4
width of area in units of mounting heights
1.67 MH
Width of Roadway in units of
STEPQ Mounting Height equals 50'
divided by 30' or 1.67 MH. .
hen lightin9 a roadway from the center median strip also d~term£ne
the house side coefficient of utilization in the same manner. Add
th±s value to the street side value and use the total value in the
formula.
Klm Lighting, Inc. D 3