Selection for Street Light Luminar-(PART-3)


Type of Street Light Lamp:

  • Street lighting Lamps normally used three types High intensity discharge (HID) lamps, High pressure sodium vapor (HPSV), Metal halide (MH), or Mercury vapor (MV).
  • However Mainly Lamps for Street lighting can be divided into three main categories (1) incandescent lamps and (2) luminescent gaseous discharge lamps. (3) LED
  • The lamps used in street lighting today are mostly High Intensity Discharge (HID) lamps that include high pressure sodium, low pressure sodium, high pressure mercury and metal halide lamps.
  • In order to reduce the emission of greenhouse gases, the use of energy efficient lamps such as Light Emitting Diodes (LED) for Street lighting has increased.Untitled

 (1) Incandescent (INC):

  • The incandescent or filament lamp was for many years the most commonly used. However, its low efficacy and short rated life have made it undesirable for new installations.
  • Advantage:
  • Inexpensive
  • Available in Different Configurations & Colors
  • No warm up is required
  • Easily controlled
  • Dis Advantage:
  • Inefficient ( 10-25 lumens/watt )
  • Short lamp life
  • Vibration sensitive
  • Over-voltage sensitive

 (a) Fluorescent (FL):

  •  At many places tube lights are used for Street Light lighting.
  • Tube lights in general are available in lower wattages and they cannot produce the same kind of brightness as a Halogen or Sodium Vapour lamp. So they should not be used to replace Halogen lamps, as they cannot produce the same amount of brightness
  • Lamps are available in the following configurations: T5,T8,T10,T12,T17Untitled
  • Standard Fluorescent Lamps T8 Lamps: 32W and 55W
  • Typically used with electronic ballast
  • Standard Fluorescent Lamps T5 Lamps: 14W, 21W, 24W, and 35W
  • Typically is used with electronic ballast
  • Standard Fluorescent Lamps T12 Lamps: Standard lamp wattages
  • Advantages
  • Efficient(75+ lumens/watt)
  • Available in many configurations
  • Desirable colors available (2,700K to 4,100K)
  • Long life (6,000 –20,000 hours)
  • Disadvantages
  • Require a ballast
  • Temperature sensitive
  • May require special controls

 (b) Tungsten-Halogen Lamps:

  • Halogen lamp is incandescent Type lamp. It has a tungsten filament filled with halogen gas.


  • Advantages
  • More compact
  • Longer life
  • More light
  • Whiter light (higher color temp.)
  • Disadvantages
  • Cost more
  • Increased IR
  • Increased UV
  • Light Color: Whit Yellow ,light Blue Color
  • Efficiency: Poor Efficiency (10 to 18 lumen/Watt)
  • Lamp Life: Long Life ( 2400 Hours)
  • Initial Cost: High initial Cost
  • Warm up Time:

Application: For outdoor areas/ parking lot lighting

 (2) High Intensity Discharge (HID) Lamps:

  • HID lamps in general require an external ballast to operate. HID lamps usually take between 1 and 5 minutes to reach full brightness, and if there is a dip in electricity, these lamps will shut off.
  • HID lamps must cool sufficiently to re strike, which usually takes from 1 minute to 10 minutes.
  • There are Mainly Two type of High discharge lamp
  • (1) High Pressure Lamp (HP)
  • (A) Mercury Vapor Lamp(MV)
  • (B) Metal Halide Lamp
  • (C) Sodium Lamp
  • (2) Low Pressure Lamp (LP)
  • (a) Mercury Fluorescent Tube
  • (b) Sodium Lamp
  • Ballasts, which are required by both fluorescent and HID lamps, provide the necessary circuit conditions (voltage, current, and wave form) to start and operate the lamps.
  • HID Lamps Characteristics
  • All HID lamps utilize an internal arc tube and outer envelope construction
  • All HID lamps require ballast for operation.
  • All HID lamps require warm up period
  • All HID lamps require cool-down period before they can re-strike

 (A) High Pressure Mercury Vapor Lamps (HPMV):

  • It is oldest Type of Lamp in HID Type.
  • Prior to the introduction of HPS lamps, MV was the most commonly used light source in highway applications. The MV lamp produces a bluish white light and is not as efficient as the HPS lamp.
  • Lamp sizes: 50,70,100,150,175,200,250,350, 400, and 450W
  • Advantage:
  • Mercury vapor lamps can provide certain low cost options for replacing less efficient lamps such as incandescent lamps without changing the fixtures.
  • Pulse start MH lamps utilize an improved ballast design to improve operation.
  • Higher efficacy
  • Faster warm-up and re-strike longer life
  • Better color uniformity
  • Energy & maintenance savings (15%)
  • Disadvantages:
  • Due to their lower efficacy and poor color rendition they are seldom used in new construction. Color shift toward the end of lamp life
  • Some lamps are designed for enclosed fixtures only
  • Orientation sensitive ( horizontal vs. vertical )
  • Light Color: Bluish white ,Pale Blue-Green Color
  • Efficiency: Lowest Efficiency in HID Type (30 to 65 lumen/Watt)
  • Lamp Life: Long Life ( 2400 Hours)
  • Initial Cost: Low initial Cost
  • Warm up Time: Faster warm-up and re-strike longer life
  • Application: For outdoor areas/ parking lot lighting ,farm light, fish pond

 (B) High Pressure Metal Halide lamps (MPMH):

  • MH lamps produce better color at higher efficiency than MV lamps. However, life expectancy for MH lamps is shorter than for HPS or MV lamps.
  • They also are more sensitive to lamp orientation than other light sources.
  • Metal Halide bulbs are as energy efficient as Sodium Vapour lamps.
  • Metal halide lamps are similar in construction to MV lamps. Some MH lamps can be operated off Mercury Vapor ballasts.
  • MH lamps offer a number of advantaged over MV lamps.


  • Light Color: A crisp clear white lights
  • Efficiency: Quit Efficient (80 lumen/Watt)
  • Lamp Life: Less (6000-20000 hrs)
  • Warm up Time:2-3 minutes, hot re-strike 10-20 minutes.
  • Application: It is used where color rendering is critical, such as car lots, service stations, athletic fields, industrial manufacturing.

 (C) High Pressure Sodium Vapor Lamp (HPSV):

  • High pressure sodium lamps are used for both interior and exterior applications and mainly used for street lighting.
  • HPS is higher efficient and better choice than metal halide for street light applications.
  • HPS is the energy efficient options for halogen lamps as they provide double the amount of brightness for the same amount of wattage.
  • HPS lamps differ from mercury and metal-halide lamps because HPS do not contain starting electrodes, the ballast circuit includes a high-voltage electronic starter.
  • The arc tube is made of a ceramic material


  • Advantages:
  • If a Halogen is replaced with Sodium Vapour lamp, 20-25% savings can be achieved.
  • Disadvantages:
  • Their brightness is highest in the canter (just below the pole) and is lesser on the outside
  • Light Color: golden-yellowish-White, Orange color light.
  • Advances in electronics now make it possible to dim HPS fixtures in a cost effective manor such as production areas and warehouses.
  • Efficiency: Quit Efficient (80 to 100lumen/Watt)
  • Lamp Life: Long Life (2400 Hours)
  • Warm up Time: 10 minutes, hot re-strike within 60 seconds
  • Operating sodium at higher pressures and temperatures makes it highly reactive
  • Application:Mostly use on Street lighting.
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