Selection for Street Light Luminar-(PART-2)

Classification of Street:


Classification Roadway Traffic
Classification Number Number of Vehicles per Hour
Maximum Night Hour Both Direction
Very light traffic Under 150
Light traffic 150 500
Medium traffic 500 1200
Heavy traffic 1200 2400
Very heavy traffic 2400 4000
Heavy traffic Over 4000


Classification of Pedestrian Traffic
Light or No Traffic Residential, warehouse areas on express / elevated depressed roadways
Medium Traffic Secondary business streets and some industrial roads
Heavy Traffic Business streets.


Mounting Height of Street Light Laminar:

  •  The distance the lamp is mounted above the roadway will affect the illumination intensity, uniformity of brightness, area covered, and relative glare of the unit.
  • Higher mounted units will provide greater coverage, more uniformity, and reduction of glare, but a lower illumination level.
  • It is necessary to weigh the effects of larger lamps against a greater number of smaller units at lower mounting heights with maximum glare potential.
  • The height of luminaries above the roadway surface varies from 5 Meter to more than 20 Meter.
  • Conventional roadway lighting utilized mounting height of 8 to 20 Meter. The lower mounting heights require the use of cutoff or semi-cutoff luminary’s distribution to minimize glare.

Height of Pole Application
6 Meter For streets ,alleys, public gardens and parking lots
8 Meter Urban traffic route, multiplicity of road junctions,
Narrow roads such as local access roads in residential areas in which a mounting height between 10 M or 12 M and 5 M or 6 M is required.
10 Meter Urban traffic route, For wide heavily used routes where a large number of intersection, bends can lead to a short spacing making the use of 12 M mounting height uneconomical.
12 Meter Wide or heavily used routes where advantage can be taken of a longer spacing of luminaries.
18 Meter and above High mast lighting poles shall be installed at large-scale area such as airports, dockyards, large industrial areas, sports areas and road intersections

Type of Road Pole Pole Height Laminar Watt Type of Laminar
Rural Aluminum or Steel Pole 10 to 16 Meter 250W to 400W HPS
Urban Aluminum 10 to 13 Meter 250W to 400W HPS (Cut off or Semi Cut off)

 High Mast Lighting Systems:

  • High mast lighting has 3 or 4 no’s of 1000 watt HPS luminaries mounted on poles /towers, at mounting heights (30 Meter). It develops a highly uniform light distribution.
  • Advantage:
  • Excellent uniformity of illumination, reduce glare with a substantially smaller number of pole locations.
  • Application:
  • Where continuous lighting is desirable such as lighting of toll plazas, rest areas ,parking areas, general area lighting, highways , traffic lanes.
  • High mast lighting is also desirable where there is minimal residential area.
  • High Mast used at remote location to eliminates the need for maintenance, vehicles obstructing traffic on the roadway.
  • High Mast having symmetric or asymmetric distribution
  • The design and installation of high mast lighting equipment is more complex than conventional lighting.


Correction Lamp Comparison Chart (Bureau of Energy Efficiency, Delhi)

Lamp Type Lamp ( Watts) Efficacy (Lumens /Watt) ColorRender


LampLife (Hr) Remarks
Incandescent (GLF) Lamps:
(Incandescent bulbs) 15,25,40,60,75,100,150,200, 300,500               (no ballast) 8 to 17 100 1000  
Tungsten Halogen  75,100,150,500,1000,2000 (no ballast) 13 to 25 100 2000  
Fluorescent Tube lights(Argon filled) 20,40,65, (32,51,79) 31 to 58 67 to 77 5000  
Fluorescent Tubular Lamp (T5) 18,20,36,40,58,65 100 to 120 Very Good 15,000 to 20,000  Energy-efficient,long lamp life,

only available in low wattages

Compact Fluorescent Lamps (CFLs) 5,7,9,11,18,24,36 26 to 64 85 8000  
HID Lamps:
High Pressure MercuryVapor (HPMV) 80,125,250,400,1000,2000 25 to 60 45 (Fair) 16,000 to 24,000 High energy use,Poor lamp life
High Pressure   Metal Halide Lamps (HPMH) 70,150,250, 400,1000,2000 62 to 72 70 (Excellent) 8000 to 12000 High luminous efficacy, Poor lamp life
High Pressure SodiumVapor Lamps (HPSV) 70,150,250,400,1000 69 to 108 25 to 60 (Fair) 15000 to 24000 Energy-efficient, poor color rendering
Low Pressure Sodium Vapor Lamps (LPSV) 35,55,135 90 to 133 Very Poor 18000 to 24000 Energy-efficient, very poor color rendering
Low Pressure Mercury   Fluorescent TubularLamps (T8 & T12) 35,55,135 30 to 90 Good 5000 to 10000 Poor lamp life, medium energy use, only available in low wattages
LED Lamps
Light Emitting Diode (LED)   70 to 160 Good 40,000 to   90,000 High energy savings, low maintenance, long life, no mercury. High investment cost, nascent technology

About Jignesh.Parmar
Jignesh Parmar has completed M.Tech (Power System Control), B.E(Electrical) from Gujarat University. He has more than 13 years experience in Power Transmission-Power Distribution-Electrical energy theft detection-Electrical Maintenance-Electrical Projects(Planning-Designing-coordination-Execution). He is Presently associate with one of the leading business group as a Deputy Manager at Ahmedabad,India. He is Freelancer Programmer of Advance Excel and design useful Excel Sheets of Electrical Engineering as per IS,NEC,IEC,IEEE codes. He is technical Author for "Electrical Mirror" and "Electrical India" Magazines. 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.

2 Responses to Selection for Street Light Luminar-(PART-2)

  1. Omutinyu D. Shitandi says:

    You do me wonderful keep it up and thanks.

  2. Oladimeji Abayomi Julius says:

    You are really solving people’s problems, pls keep it up

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: