Calculate Street Light Pole’s Distance / Fixture Watt / Lighting Area
June 2, 2014 30 Comments
(1) Calculate Distance between each Street Light Pole:
Example: Calculate Distance between each streetlight pole having following Details,
 Road Details: The width of road is 11.5 Foot.
 Pole Details: The height of Pole is 26.5 Foot.
 Luminaire of each Pole: Wattage of Luminaries is 250 Watt, Lamp Out Put (LL) is 33200 Lumen, Required Lux Level (Eh) is 5 Lux, Coefficient of Utilization Factor (Cu) is 0.18, Lamp Lumen Depreciation Factor (LLD) is 0.8, Lamp Lumen Depreciation Factor (LLD) is 0.9.
 Space Height Ratio should be less than 3.
Calculation:
 Spacing between each Pole=(LL*CU*LLD*LDD) / Eh*W
 Spacing between each Pole=(33200×0.18×0.8×0.9) / (5×11.5)
 Spacing between each Pole= 75 Foot.
 Space Height Ratio = Distance between Pole / Road width
 Space Height Ratio = 3. Which is less than define value.

Spacing between each Pole is 75 Foot.
(2) Calculate Street Light Luminaire Watt:
Example: Calculate Streetlight Watt of each Luminaire of Street Light Pole having following Details,
 Road Details: The width of road is 7 Meter. Distance between each Pole (D) is 50 Meter.
 Required Illumination Level for Street Light (L) is 6.46 Lux per Square Meter. Luminous efficacy is 24 Lumen/Watt.
 Maintenance Factor (mf) 0.29, Coefficient of Utilization Factor (Cu) is 0.9.
Calculation:
 Average Lumen of Lamp (Al) = 8663 Lumen.
 Average Lumen of Lamp (Al) =(LxWxD) / (mfxcu)
 Average Lumen of Lamp (Al)= (6.46x7x50) / (0.29×0.9)
 Average Lumen of Lamp (Al)=8663 Lumen.
 Watt of Each Street Light Luminar = Average Lumen of Lamp / Luminous efficacy
 Watt of Each Street Light Laminar = 8663 / 24

Watt of Each Street Light Luminaire = 361 Watt
(3) Calculate Required Power for Street Light Area:
Example: Calculate Streetlight Watt of following Street Light Area,
 Required Illumination Level for Street Light (L) is 6 Lux per Square Meter.
 Luminous efficacy (En) is 20 Lumen per Watt.
 Required Street Light Area to be illuminated (A) is 1 Square Meter.
Calculation:
 Required Streetlight Watt = (Lux per Sq.Meter X Surface Area of Street Light) / Lumen per Watt.
 Required Streetlight Watt = (6 X 1) / 20.

Required Streetlight Watt = 0.3 watt per Square Meter.
Your sincere effort and goodwill contribution are to be thanked at all times.
Paneer Selvam  Manager (Marketing)
Emirates Transformer & Switchgear Limited
Jebel Ali  Dubai  United Arab Emirates
I acknowledge the hard efforts of sharing thoughts among all educators, scientists of Mr. Jignesh Parmar, see my thoughts for all educators: We all remain as students in our short life on this world?
Helping others (students) to develop a deep love and respect for themselves, others, and their environment occurs through an open sharing of ideas and a judicious approach to discipline. When the voice of each student is heard, and environment evolves where students feel free to express themselves. Class meetings are one way to encourage such dialogue. I believe children have greater respect for their teachers, their peers, and the lessons presented when they feel safe and sure of what is expected of them. In setting fair and consistent rules initially and stating the importance of every activity, students are shown respect for their presence and time. In turn they learn to respect themselves, others, and their environment.
thanks for the knowledge shared to us and it is very useful refference on how to calculate or computation for the street light proper engineering works
It seems so informative for the engineers especially electrical engineers for their practical knowledge improvement and of course for the timely help for urgent reference..
very useful information. but i will like to ask, what if u were not given the illuminance, but u were given the intensity, area served and efficacy, how do u find the power, based on an operation of 12hrs per day?
It is Really helped me in real time calculation.
Thank you so much for your sharing.
Very helpful
I have 8m pole and the distance between one pole to the next is 50m, the width of the road is 30m. I want to find the wattage of the LED lamp that will give the max illumination. HOW DO I GET IT. Please help me..
Dear sir ,i need simple calculation of indoor lighting lux design.
When a number of Single phase loads are powered/fed through a TPN DB. How do we get/calculate the Three Phase Total Loading of the DB, especially to aid sizing of the DB’s 3Phase Main Breaker and Feed Cable selection?
Height of high mast is 16 meter, The area of ground 85000 sq meter (340 meter long and 250 meter wide). Please suggest me, how much high mast will be installed and no. of lamps with wattage and type.
please SUGGEST ME .
DEAR SIR,
HOW TO CALCULATE THE UTILIZATION FACTOR AND MAINTENANCE FACTOR FOR ILLUMINATION CALCULATION
My road width is 5Mts,Distance between poles 20Mts,height o pole is 8mts
What LED i can use for this application
Any post regarding LED selectio.Will be helpful
can anybody please guide me regarding how much wattage of LED will be suficient for a 16 metre height highmast?
Dear Sir ,
when you have calculated the spacing between each pole in that case why you use same factor in two time : Lamp Lumen Depreciation Factor (LLD) is 0.8, Lamp Lumen Depreciation Factor (LLD) is 0.9 .
I think another one will be – Light Loss Factor
Thanks
Regards
Shiv Kumar
I think so !
please let me know the distance between high mast light and residential buildings
Please provide us with solar street lighting design, what is the average lux requirement for road lighting? which codes can I refer to?
The width of Street is 4m.25watt led is proposed in the street.What should be the height of pole to achieve lux level as per norms in C type roads.
i have 50 watt street light of 140 lm/watt .so please send how much area it will cover. if i will mount it at 15ft,20ft,25ft.
i have godown of 136 mts lenght and 30 mtrs width. the space available for solar mounting is 50 mtrs away from the godown.i want to mount 20 watts lighting system in all 44 pillars cris cross.please suggest me what rating convertor or invertor can be used? what will be the rating of my panel in KW ,as well as battery bank requirements..what will be the witing details do please suggest me
Siddharth jain.
how to calculate lumens of the lamp(LL),wattage of luminarie=250 watt
1 watt=50 lumens
LL=205*50=12500 lumens
for your calculation LL=33200 Lumens(how to calculate)
dear Mr. Parmar,
Good Day!
Am Mr. Eswaran Ravichandran Managing director of GREEN GULF ENGINEERS. Now i have one project its very new area. I need your support for complete electrical design and street light design as per local municipality standard. I leave my mailing id here with this below mentioned box. Kindly share with your experience with us. other things we discuss via email else over telephone or skype
The best information.
thank you very much bro god bless
Distance between 2Poles , Pole Heightx3.5Times (Min.) Pole Heightx4.5Times.
Ex: For 8m Pole 28m(Min.) and 36m(Max.)
under (2) calculate street light luminaire watt it is mentioned as lux per squire meter it should be lumens per squire meter. Lux means lumens per squire meter. The distance of 50 meter with 7 meter high pole seems more . Either the spacing should be less or the pole height should be more. for uniformity of lux level . you need to see the polar curve of the fitting. the value worked out seems to be just under the luminaire