# Calculate Street Light Pole’s Distance / Fixture Watt / Lighting Area

## (1) Calculate Distance between each Street Light Pole:

Example: Calculate Distance between each streetlight pole having following Details,

• 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.

## (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

## (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.

Jignesh Parmar has completed M.Tech (Power System Control), B.E(Electrical). He is member of Institution of Engineers (MIE) and CEng,India. Membership No:M-1473586.He has more than 16 years experience in Transmission -Distribution-Electrical Energy theft detection-Electrical Maintenance-Electrical Projects (Planning-Designing-Technical Review-coordination -Execution). He is Presently associate with one of the leading business group as a Deputy Manager at Ahmedabad,India. He has published numbers of Technical Articles in “Electrical Mirror”, “Electrical India”, “Lighting India”,”Smart Energy”, “Industrial Electrix”(Australian Power Publications) Magazines. He is Freelancer Programmer of Advance Excel and design useful Excel base Electrical Programs as per IS, NEC, IEC,IEEE codes. He is Technical Blogger and Familiar with English, Hindi, Gujarati, French languages. He wants to Share his experience & Knowledge and help technical enthusiasts to find suitable solutions and updating themselves on various Engineering Topics.

### 37 Responses to Calculate Street Light Pole’s Distance / Fixture Watt / Lighting Area

1. Panneer SELVAM (ETS Limited, Dubai) says:

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

2. 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.

• DWIGHT R. MACHICA says:

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..

4. Mariegold says:

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?

5. Tabish Hilal says:

It is Really helped me in real time calculation.

6. Thet says:

Thank you so much for your sharing.

7. Juma Ganiyu says:

8. Juma Ganiyu says:

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..

9. Dear sir ,i need simple calculation of indoor lighting lux design.

10. AbduRahman Yusuf says:

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 3-Phase Main Breaker and Feed Cable selection?

11. Sunil says:

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.

12. ONASIS says:

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

15. Anupam Saha says:

can anybody please guide me regarding how much wattage of LED will be suficient for a 16 metre height highmast?

16. Shiv Kumar says:

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

17. dinesh kumar says:

please let me know the distance between high mast light and residential buildings

18. Nazari says:

Please provide us with solar street lighting design, what is the average lux requirement for road lighting? which codes can I refer to?

19. Gurvinder Pal Singh says:

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.

20. kunal says:

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.

21. siddharth jain says:

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.

22. kulanyhai velu says:

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)

23. eswaran says:

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

24. Marifatullah says:

The best information.

thank you very much bro god bless

26. Mohsin says:

Distance between 2Poles , Pole Heightx3.5Times (Min.) Pole Heightx4.5Times.
Ex: For 8m Pole 28m(Min.) and 36m(Max.)

27. kulbhushan lal seth says:

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

28. bob craven says:

I have noticed that in town 30 mph limits there are steet lamps about 25 metrs apart and the poles are low ones about 5/6 meters only wheras on the main roads out of town at apeeed in excess of 30 mph but only up toi 60 mph the poles are aboiut 15 metres and give greater illumination and are spaced about 45 metres apart.

Is there any generallity to this nationwide or does every council or the Hihways authotrity do there own thing when it come down to the lamp posts spacings.

ie can we say that town lights are so many metres apart say between 20 and 35 metres and that urban lights are again so many metres apart. say between 40 and 50 metres.

29. kusanale says:

Sir, what is the standard value of space to height ratio

30. Teja says:

Super sar and hiw to caluculate the cabel size and amps load tell ne sar