Calculate Motor Pump Size

• Calculate Size of Pump having following Details
• Static Suction Head(h2)=0 Meter
• Static Discharge Head (h1)=50 Meter.
• Required Amount of Water (Q1)=300 Liter/Min.
• Density of Liquid (D) =1000 Kg/M3
• Pump Efficiency (pe)=80%
• Motor Efficiency(me)= 90%
• Friction Losses in Pipes (f)=30%

Calculations:

• Flow Rate (Q) =Q1x1.66/100000 =300×1.66/100000= 0.005 M3/Sec
• Actual Total Head (After Friction Losses) (H) = (h1+h2)+((h1+h2)xf)
• Actual Total Head (After Friction Losses) (H)=50+(50×30%)= 65 Meter.
• Pump Hydraulic Power (ph) = (D x Q x H x9.87)/1000
• Pump Hydraulic Power (ph) = (1000 x 0.005 x 65 x9.87)/1000 =3KW
• Motor/ Pump Shaft Power (ps)= ph / pe = 3 / 80% = 4KW
• Required Motor Size: ps / me =4 / 90% = 4.5 KW

• Required Size of Motor Pump = 4.5 HP or 6 HP

Calculate Size of Cable for Motor (As NEC)

NEC Code 430.22 (Size of Cable for Single Motor):

• Size of Cable for Branch circuit which has Single Motor connection is 125% of Motor Full Load Current Capacity.
• Example: what is the minimum rating in amperes for Cables supplying 1 No of 5 hp, 415-volt, 3-phase motor at 0.8 Power Factor. Full-load currents for 5 hp = 7Amp.
• Min Capacity of Cable= (7X125%) =8.75 Amp.

 NEC Code 430.6(A) (Size of Cable for Group of Motors or Elect. Load).

• Cables or Feeder which is supplying more than one motors other load(s), shall have an ampacity not less than 125 % of the full-load current rating of the highest rated motor plus the sum of the full-load current ratings of all the other motors in the group, as determined by 430.6(A).
• For Calculating minimum Ampere Capacity of Main feeder and Cable is 125% of Highest Full Load Current + Sum of Full Load Current of remaining Motors.
• Example:what is the minimum rating in amperes for Cables supplying 1 No of 5 hp, 415-volt, 3-phase motor at 0.8 Power Factor, 1 No of 10 hp, 415-volt, 3-phase motor at 0.8 Power Factor, 1 No of 15 hp, 415-volt, 3-phase motor at 0.8 Power Factor and 1 No of 5hp, 230-volt, single-phase motor at 0.8 Power Factor?
• Full-load currents for 5 hp = 7Amp.
• Full-load currents for 10 hp = 13Amp.
• Full-load currents for 15 hp = 19Amp.
• Full-load currents for 10 hp (1 Ph) = 21Amp.
• Here Capacity wise Large Motor is 15 Hp but Highest Full Load current is 21Amp of 5hp Single Phase Motor so 125% of Highest Full Load current is 21X125%=26.25Amp
• Min Capacity of Cable= (26.25+7+13+19) =65.25 Amp.

 NEC Code 430.24 (Size of Cable for Group of Motors or Electrical Load).

• As specified in 430.24, conductors supplying two or more motors must have an ampacity not less than 125 % of the full-load current rating of the highest rated motor +  the sum of the full-load current ratings of all the other motors in the group or on the same phase.
•  It may not be necessary to include all the motors into the calculation. It is permissible to balance the motors as evenly as possible between phases before performing motor-load calculations.
• Example:what is the minimum rating in amperes for conductors supplying 1No of 10 hp, 415-volt, 3-phase motor at 0.8 P.F and 3 No of 3 hp, 230-volt, single-phase motors at 0.8 P.F.
• The full-load current for a 10 hp, 415-volt, 3-phase motor is 13 amperes.
• The Full-load current for single-phase 3 hp motors is 12 amperes.
• Here for Load Balancing one Single Phase Motor is connected on R Phase Second in B Phase and third is in Y Phase.Because the motors are balanced between phases, the full-load current on each phase is 25 amperes (13 + 12 = 25).
• Here multiply 13 amperes by 125 %=(13 × 125% = 16.25 Amp). Add to this value the full-load currents of the other motor on the same phase (16.25 + 12 = 28.25 Amp).
• The minimum rating in amperes for conductors supplying these motors is 28 amperes.

 NEC 430/32 Size of Overload Protection for Motor:

• Overload protection (Heater or Thermal cut out protection) would be a device that thermally protects a given motor from damage due to heat when loaded too heavy with work.
• All continuous duty motors rated more than 1HP must have some type of an approved overload device.
• An overload shall be installed on each conductor that controls the running of the motor rated more than one horsepower. NEC 430/37 plus the grounded leg of a three phase grounded system must contain an overload also. This Grounded leg of a three phase system is the only time you may install an overload or over – current device on a grounded conductor that is supplying a motor.
• To Find the motor running overload protection size that is required, you must multiply the F.L.C. (full load current) with the minimum or the maximum percentage ratings as follows;

Maximum Overload

• Maximum overload = F.L.C. (full load current of a motor) X allowable % of the maximum setting of an overload,
• 130% for motors, found in NEC Article 430/34.
• Increase of 5% allowed if the marked temperature rise is not over 40 degrees or the marked service factor is not less than 1.15.

Minimum Overload

• Minimum Overload = F.L.C. (full load current of a motor) X allowable % of the minimum setting of an overload,
• 115% for motors found in NEC Article 430/32/B/1.
• Increase of 10% allowed to 125% if the marked temperature rise is not over 40 degrees or the marked service factor is not less than 1.15

 

How to Design efficient Street lighting-(Part-6)

(3) Light trespass:

• Light trespass is condition when spill (Unwanted or Unneeded) light from a streetlight or floodlight enters a window and illuminates an indoor area.

 How to Reduce Trespass

• Select luminaries, locations, and orientations to minimize spill light onto adjacent properties.
• Use well-shielded luminaries.
• Keep floodlight aiming angles low so that the entire beam falls within the intended lighted area.

 Difference between full cutoffs and fully shielded:

• The full cutoff has is luminaries that have no direct up light (no light emitted above horizontal) and 10% of light intensity between 80° and 90°.
• The term full cutoff is often substituted for the term fully shielded.
• The both terms are not equivalent. Fully shielded luminaires emit no direct up light, but have no limitation on the intensity in the region between 80° and 90°
• Luminaires that are full cutoff, cutoff, semi cutoff, and non cutoff , may also qualify as fully shielded.

• There is also a confusing assumption that a luminaire with a flat lens qualifies as a full cutoff luminaries. While this may be true or not in some Lighting Fixtures case.

• Fully shielded means, a lighting fixture constructed in such a manner that the bulb should be fully recessed into Fixture so that all light is directed downward below the horizontal.
• The fixture is angled so the lamp is not visible below the barrier (no light visible below the horizontal angle).

(G) Selection of Luminas:

(1) Types of Lighting Source

• Street Lights are mostly Low-pressure sodium (LPS), High-pressure sodium (HPS), Metal halide and Light emitting diodes (LED).
• LPS is very energy efficient but emits only a narrow spectrum of pumpkin-colored light that some find to be undesirable.
• LPS is an excellent choice for lighting near astronomical observatories and in some environmentally sensitive areas.
• HPS is commonly used for street lighting in many cities. Although it still emits an orange-colored light, its coloring is more “true to life” than that of LPS.
• Where it’s necessary to use white light, there are metal halide and LEDs.

• High-pressure sodium lamps should be used for expressways, main roads, secondary roads and branch roads.
• Low-power metal halide lamps should be used in mixed traffic roads for motor vehicles and pedestrians in residential areas.
• Metal halide lamps can be used for motor vehicle traffic, such as city centers and commercial centers, which require high color identification.
• Metal halide lamps, CFL lamps are used at Pedestrian streets in industrial areas, sidewalks in residential areas, and sidewalks on both sides of motorway traffic.
• LED streetlights are more durable, longer lasting, efficiency, dimmable capacity and cost effective than traditional lights.
• LED also enhances public safety by delivering superior visible light while providing the environmental advantage of using less energy.

 (2) Color Rendering Index (CRI):

• CRI Measures the ability of the artificial light to show or reproduce the colors of the road or objects on the road, relative to a natural light source.
• The natural light source (the sun) has CRI of 100. The higher
• This index the better the visibility will be. For all types of road CRI ≥ 70 is recommended.

(3) Efficacy

• At the low end LED efficacy starts at 70 lumens per watt (lm/W) and reaches as high as 150 lm/W.
• While the mean efficacy for outdoor area fixtures is slightly lower than common indoor fixtures such as troffers and linear lighting about 100 lm/W for area lights compared to about 110 lm/W for troffers and linear fixtures this difference is not significant. It may be the result of outdoor area lights requiring more precise luminous intensity distributions and other factors unique to outdoor lighting.

(4) Fixture Protection:

• When using sealed road lighting, the protection level of the light source cavity should not be lower than IP54.
• For roads and places with dangerous environmental pollution and heavy maintenance, the protection level of the light source cavity should not be lower than IP65.
• The degree of protection of the lamp electrical appliance cavity should not be lesser than IP43.
• Lamps with excellent corrosion resistance should be used in areas or places with high levels of corrosive gases such as acid and alkali in the air.

(H) Effective Road Lighting:

• Sufficient illumination.
• Good uniformity.
• No Glare.
• Low consumption.
• No Color Temperature abnormalities
• No Zebra effect
• Shielded lighting to ensure light is pointed downwards
•  Completely uniform illuminance.
• No requirement for over lighting to obtain sufficient average illumination.
• Absence of glare.
• Absence of low angle radiation that causes sky glow.
• Control of light trespass.
• High redundancy.

Effective Lightning
Features	Benefits
Proper pole height & spacing	Provide uniform light distribution
Proper Luminaire aesthetics	Blends in with the surroundings
Good maintenance	Reduce problems in lightning
High lamp efficiency	Minimize energy cost
Life of Luminaire	Reduce lamp replacement cost
Good color rendering	Helps object appear more natural
Proper light distribution	Provide required light on roads
Cost effectiveness	Lowers operating cost
Minimizing light pollution & glare	Reduce energy use

 

Effective Energy-efficient Street Lighting Systems (NYSERDA, 2002)
Features	Benefits
Proper pole height and spacing	Provides uniform light distribution, which improves appearance for safety and security Meets recommended light levels Minimizes the number of poles, reducing energy and maintenance costs
Proper luminaire aesthetics	Blends in with the surroundings
High lamp efficacy and Luminaire efficiency	Minimizes Energy cost
Life of the luminaire and other components	Reduces lamp replacement costs
Cost effectiveness	Lowers operating cost
High Lumen Maintenance	Reduces lamp replacement costs
Good color rendering	Helps object appear more natural and pleasing to the public Allows better recognition of the environment, improves security
Short lamp Re strike	Allows the lamp to quickly come back after a power interruption
Proper light distribution	Provides required light on the roads and walkways
Proper Cutoff	Provides adequate optical control to minimize light pollution
Minimizing light pollution and Glare	Reduces energy use
Automatic Shutoff	Saves energy and maintenance costs by turning lamps off when not needed

 

Minimum Value of Street Light Designing
Descriptions	Min Value
Watt	400
Lumens Per Watt	80 To 140
Voltage	230Volt
Frequency	50 To 60Hz
Power Factor	More than 95
THD	< 20%
Life Hours	70,000 hours
Color Temperature	4000K  To  5000K
CRI	More than 75
Beam Angle / Beam Pattern	Type 2,3,4,5
Operating Temperature	(-)25°C To (+)50°C
Working Humidity	10% To 90% RH
IP Rating	IP67
Dimmable	0-10V
Optic Lens Material	High Polycarbonate (PMMA)
Forward Current	>600mA
Housing	IP65 – Aluminum Alloy and PC Lens
Dimension	18.23″ X 13.58″ X 4.57″
Weight	15.30 lbs – 34.39 lbs
Warranty	10 Years

How to Design efficient Street lighting-(Part-5)

(2) Surround Ratio (SR):

• Road lighting should be illuminate not only the road, but also the adjacent areas so motorists can see objects in the periphery and anticipate potential road obstructions (e.g., a pedestrian about to step onto the road).
• The SR is the visibility of the road’s periphery relative to that of the main road itself.
• As per industry standards, SR should be at least 50.
• Figure show how road lighting should illuminate both the main road and its periphery.

(F) Lighting Pollutions

• Light pollution is an unwanted consequence of outdoor lighting and includes such effects as sky glow, light trespass, and glare. 
• 30 to 50% of all light pollution is produced by roadway lighting that shines wasted light up and off target.

(1) Glare:

• Glare is the condition of vision in which there is discomfort or a reduction in the ability to see significant objects. Glare affects human vision and it is subdivided into four components, Disability Glare, Discomfort Glare, Direct Glare and Indirect Glare.
• By origin

1. Direct Glare
2. Indirect (reflected) Glare

• By effect on people

1. Disability Glare
2. Discomfort Glare

• Disability glare:
• Disability glare is the glare that results in reduced visual performance and visibility.
• Since disability glare reduces the ability to perceive small contrasts.
• It can impair important visual tasks in traffic such as detecting critical objects, controlling headlights, and evaluating critical encounters, making glare a potential danger for road users.
• LED light sources can provide very high luminance lev­els which may cause glare. For this reason, LED lamps are commonly equipped with diffusers to reduce this luminance.
• Disability glare may vary for dif­ferent individuals and it can be calculated objectively.
• In a particu­lar illuminated environment, the human eye will be able to detect differences in luminance down to a certain threshold. This threshold can be compared for a situa­tion in the same environment when a source of glare is added. By comparing these thresholds, the threshold increment can be derived.
• Discomfort glare:
• Discomfort glare is the glare producing discomfort. It does not necessarily interfere with visual performance or visibility.
• As vertical light angles increase, discomforting glare also increases
• Discomfort glare, on the other hand, is a subjective phenomenon and there is no method for its Rating.
• Although the 9-point De Boer scale (ranging from “1” for “unbearable” to “9” for “unno­ticeable”) is the most widely used in the field of auto­motive and public lighting.
• Direct Glare:
• Direct glare is caused by excessive light entering the eye from a bright light source. The potential for direct glare exists anytime one can see a light source. With direct glare, the eye has a harder time seeing contrast and details.
• A system designed solely on lighting levels, tends to aim more light at higher viewing angles, thus producing more potential for glare.
• Exposed bright light source, for example a dropped lens cobra head or floodlight causes of direct glare.
• Direct glare can be minimized with careful equipment selection as well as placement.

• Figure illustrates two examples of exterior lighting that results in glare.

 

• Fig shows how full cutoff luminaries (Shielded Luminaires) can minimize this direct glare. In exterior applications, use fully shielded luminaires that directs light downwards towards the ground.
• Indirect Glare: Indirect glare is caused by light that is reflected to the eye from surfaces that are in the field of view – often in the task area.
• Indirect Glare can be minimized with the type and layout of lighting equipment. Direct the light away from the observer with the use of low glare, fully shielded luminaries.
• As the uniformity ratio increases (poor uniformity), object details become harder to see.
• For roadway lighting, good uniformity shows evenly lighted pavement. However, to meet small target visibility criteria, a non uniform roadway surface may be better.
• There should be a balance between uniform perception and detecting objects on the road. Also, emphasis is put on horizontal surface uniformity. In reality, vertical surfaces may require more lighting in order to improve guidance.

How to Reduce Glare:

• Glare and light trespass are more concern when installing floodlights.
• Use shielded Light should be use to reduce Glare.
• Higher mounting heights can more effective in controlling spill light, because floodlights with a more controlled light distribution (i.e., narrower beam) may be used, and the floodlights may be aimed in a more downward direction, making it easier to confine the light to the design area.
• Lower mounting heights increase the spill light beyond the property boundaries. To illuminate the space satisfactorily, it is often necessary to use floodlights with a broader beam and to aim the floodlights in directions closer to the horizontal than would occur when using higher mounting heights.
• Lower mounting heights make bright parts of the floodlights more visible from positions outside the property boundary, which can increase glare.

(2) Sky glow:

• Sky Glow is brightening of the night sky caused by outdoor lighting.
• Light that is emitted directly upward by luminaries or reflected from the ground is scattered by dust and gas molecules in the atmosphere, producing a luminous background. It has the effect of reducing one’s ability to view the stars in Night.

 

How to Reduce Sky Glow

• While it is difficult to accurately model sky glow, at this point it is presumed that the most important factors are light output and lamp spectral characteristics, light distribution from the luminaire, reflected light from the ground, and aerosol particle distribution in the atmosphere.
• If the quantity of light going into the sky is reduced, then sky glow is reduced. Thus, to reduce sky glow by
• By using full cutoff luminaires to minimize the amount of light emitted upward directly from the luminaire.
• Reduce Lighting Level.
• Make practice to Turn off unneeded lights
• Limited Lighting hours in outdoor sales areas, parking areas, and signages
• Installing Low-Pressure Sodium light sources, which allow astronomers to filter the line spectra from telescopic images.

How to Design efficient Street lighting-(Part-4)

(C) Lighting Factor:

(1) Maintenance Factor (Light Loss Factors) (MF)

• The Maintenance Factor (Light loss factor) is the combination of factors used to denote the reduction of the illumination for a given area after a period of time compared to the initial illumination on the same area.
• The efficiency of the luminaire is reduced over time. The designer must estimate this reduction to properly estimate the light available at the end of the lamp maintenance life.
• Luminaire maintenance factors vary according to the intervals between cleaning, the amount of atmospheric pollution and the IP rating of the luminaire.
• However, it is proposed to consider maintenance factor of not less than 0.5 for LED Road lighting installations for IP66 rated luminaires.
• The maintenance factor may range from 0.50 to 0.90, with the typical range between 0.65 To 0.75
• These maintenance factor values shall be adopted for the purposes of producing the lighting simulation design.
• The maintenance factor is the product of the following factors.
• LLF = LLD x LDD x EF
• Mostly We consider Maintenance factor from 0.8 to 0.9
• We have to choose Maintenance factor carefully by increasing maintenance factor 0.5 the spacing of pole increasing 2 meter to 2.5 meter.

Maintenance Factor	Max. Spacing of Pole (Meter)
0.95	43
0.9	40.5
0.85	38
0.8	36

(A) Lamp Lumen Depreciation Factor (LLD)

• As the lamp progresses through its service life, the lumen output of the lamp decreases. This is an inherent characteristic of all lamps. The initial lamp lumen value is adjusted by a lumen depreciation factor to compensate for the anticipated lumen reduction.
• This assures that a minimum level of illumination will be available at the end of the assumed lamp life, even though lamp lumen depreciation has occurred. This information should be provided by the manufacturer. For design purposes, a LLD factor of 0.9 to 0.78 should be used.

(B) Luminaire Dirt Depreciation Factor (LDD).

• Dirt on the exterior and interior of the luminaries and to some on the lamp reduces the amount of light reaching the roadway.
• Various degrees of dirt accumulation may be anticipated depending upon the area in which the luminaire is located. Industry, exhaust of vehicles, especially large diesel trucks, dust, etc, all combine to produce the dirt accumulation on the luminaries.
• Higher mounting heights, however, reduce the vehicle-related dirt accumulations.
• LDD factor of 0.87 to 0.95 should be used. This is based on a moderately dirty environment and three years exposure time.

(C) Equipment Factor (EF).

• Allows for variations inherent in the manufacture and operation of the equipment (i.e., luminaries, system voltage and voltage drop).
• It is generally assumed to be 95%.

(2) Coefficient of Utilization (CU):

• Coefficient of Utilization is the ratio of the luminous flux from a luminaire received on the surface of the roadway to the lumens emitted by the luminaire’s lamps alone.
• Coefficient of Utilization should be maximum.
• Coefficient of Utilization differs with each luminaire type, and depends upon mounting height, road width, and overhang.
• The coefficient of utilization (K) should be over 30% or the utilance above 40% for the road, highway, square or enclosure. Luminaires or floodlights should not by placed far from the area to be lit or, where appropriate, light projection beyond the useful zone should be minimized (K = average maintained illuminance multiplied by the surface calculation and divided by the lumens installed).

Type	Luminaries Dirt Depreciation	Luminaire Lumen Depreciation	Total Light Loss Factor
LED	0.9	0.85	0.765
HPS	0.9	0.9	0.81
LPS	0.9	0.85 (0.7 for 180W)	0.765 (0.63 for 180W)

 

Light Loss Factors
Type of Lamp	Laminar Dirt description	Light Loss Factor
HPS	0.88	0.74
Induction	0.88	0.62
LED	0.88	0.72

 

Maintenance factors
Cleaning intervals (months)	Pollution category
	High	Medium	Low
12	0.53	0.62	0.82
18	0.48	0.58	0.8
24	0.45	0.56	0.79
36	0.42	0.53	0.78

 

Maintenance Factors for 36 month cleaning interval
Factors	IP5X			IP6X
	Pollution category			Pollution category
	Low	Medium	High	Low	Medium	High
LMF	0.88	0.82	0.76	0.9	0.87	0.83
LLMF	0.89	0.89	0.89	0.89	0.89	0.89
MF	0.78	0.73	0.68	0.80	0.77	0.74

 (E) Lighting Uniformities

(1) Lighting Uniformities

• Uniformity is a description of the smoothness of the lighting pattern or the degree of the intensity of bright and dark areas on the road.
• Uniformity is a measure of how evenly distributed the light on the road is, which can be expressed as Overall Uniformity (UO) and Longitudinal Uniformity (UL).
• The uniformity ratio shall not exceed 4:1 and preferably should not exceed 3:1 except on residential streets, where 6:1 may be acceptable.

(A) Overall uniformity:

• In design, the overall uniformity (UO) is expressed as a ratio of the minimum to the average luminance on the road surface of the carriageway within the calculation area.
• UO=Lmin / Lave

• It is a measure of how evenly or uniformly illuminate on the road surface.
• A good overall uniformity ensures that all spots and objects on the road are sufficiently lit and visible to the motorist.
• The industry accepted value for UO is 30 to 0.40.

(B) Longitudinal uniformity:

• The longitudinal uniformity (UL) is expressed as the ratio of the minimum to maximum luminance along the center line of a lane within the calculation area.
• UL=Lmin / Lmax.
• Longitudinal uniformity is a measure to reduce bright and dark bands of light appearing on road lit surfaces. The effect can be somewhat hypnotic and present confusing luminance patterns.

• It is a measure to reduce the intensity of bright and dark banding on road lit surface.
• A good level of longitudinal uniformity ensures comfortable driving conditions by reducing the Pattern of high and low luminance levels on a road (i.e. zebra effect).
• It is applicable to long continuous roads.

 Combination of Overall Uniformity and Longitudinal Uniformity:

• The picture on the left shows a road with good UO while the picture on the right has low level of UO. The Road is more visible in the road with higher UO. Having higher UO allows the motorist to see the road clearly and anticipate potential road hazards (e.g. open manholes, road excavations, sharp objects on the road, people crossing the street).
• The picture on the right shows a road with low level of UL demonstrating the ‘Zebra Effect’ while the picture on the left has high level of UL without ‘Zebra Effect’.
• The ‘zebra effect’ can cause discomfort to motorists, posing a risk to road safety. Ensuring good level of uniformity can reduce the luminance level needed. 

Lighting levels
Category	Eave ( LUX)	Emin  LUX)	Uniformity ratios
			Emax : Emin	Eave : Emin
Express & Main street	30	15	3:01	2.5:1
Suburban shopping street	25	10	5:01	3:01
Subsidiary street	15	10	5:01	3:01
Other streets	15	5	10:01	5:01

 

Road Classification	Area Classification	Average  Lux	Uniformity Ratio (Aver./Min.)
Arterial (Minor & Major)	Commercial	12	3 to 1
	Intermediate	9
	Residential	6
Collector (Minor & Major)	Commercial	8
	Intermediate	6	4 to 1
	Residential	4
Local	Commercial	6
	Intermediate	5	6 to 1
	Residential	3
Alleys	Commercial	4
	Intermediate	3	6 to 1
	Residential	2
Sidewalks (Roadside)	Commercial	3	3 to 1
	Intermediate	6	4 to 1
	Residential	2	6 to 1
Pedestrian Ways		15	3 to 1

  

Illumination for Intersections
Functional Classification	Average Maintained Illumination at Pavement by Pedestrian Area Classification in Lumen			Uniformity
	High	Medium	Low	Eavg/Emin
Major/Major	37	28	19	32
Major/Collector	31	24	16	32
Major/Local	28	22	14	32
Collector/Collector	26	19	16	43
Collector/Local	23	17	11	43
Local/Local	19	15	9	65

 

Illumination for Pedestrian Areas
Maintained Illuminance Values for Walkways
Area Classification	Description	E avg (Lux)	EV min (Lux)	E avg/Emin
High Pedestrian Conflict	Mixed Vehicle and Pedestrian	22	11	43
Areas	Pedestrian Only	11	5	43
Medium Pedestrian	Pedestrian Areas	5	2	43
Conflict Areas
Low Pedestrian	Rural/Semi-Rural Areas	2	1	108
Conflict Areas	Low Density Residential (2 or fewer dwelling units per acre)	3	1	65
	Medium Density Residential (2.1 to 6.0 dwelling units per acre)	4	1	43
Pedestrian Portion of Pedestrian/Vehicular Underpasses	Day	108	54	43

How to Design efficient Street lighting-(Part-3)

(C) Lighting Fixture:

(1) Fixture’s Mounting Height:

• Higher mounting heights used in conjunction with higher wattage luminaries enhances lighting uniformity and typically reduces the number of light poles needed to produce the same illumination level.
• In general, higher mounting heights tend to produce a more cost-effective design. For practical and aesthetic reasons, the mounting height should remain constant throughout the system.
• The manufacturer’s photometric data is required to determine an appropriate mounting height.
• Typical mounting heights for highway lighting purposes range from 30 ft to 55 ft (9.1 meter to 16.8 meter).
• Mounting heights for light towers or High mast is typically 80 ft (24 m) or greater.
• The installation height is too low, the glare of the lamp increases.
• As the installation high increase, glare decreases, but the lighting utilization rate decreases.

 

(2) Fixtures Classification:

• The Illuminating Engineering Society of North America (IESNA, IES or BIS1981) provides classifications for luminaires according to their glare control and high-angle brightness.

(A) Full Cutoff (F):

• A luminaire light distribution is designated as full cutoff (F) when Zero intensity at or above horizontal (90° above nadir) and Less than 10% of lamp lumens at or above 80°.
• Full-cutoff fixtures reduce glare dramatically and eliminate direct up light by sending all their light toward the ground .This efficiency should translate into lower bulb wattages if the existing poles are used. However, some lighting engineers believe that to achieve the same illumination uniformity as their semi-cutoff counterparts, full-cutoff fixtures need to be mounted either on taller poles or closer together
• Benefits:
• Limits spill light on to adjacent property, reduces glare. No light is emitted directly from the luminaries into the sky.
• Reduce Lighting Pollution.
• Limitations:
• May reduce pole spacing to maintain uniformity and increase pole and luminaire quantities.
• Application:
• Use for roadway, parking, and other vehicular lighting applications. Minimizes glare and light pollution and light trespass.

 (B) Cutoff (C):

• A luminaries light distribution is designated as cutoff (C) when Less than 2.5% Intensity at or above horizontal (90° above nadir) and Less than 10% of lamp lumens at or above 80°.
• The direction of maximum intensity may vary but should be below 65º.
• Benefits:
• Small increase in high-angle light allows increased pole spacing.
• Cutoff system is the reduction of glare.
• Limitations:
• May allow some up light (Sky Light) from luminaries. Typically a small overall impact on sky glow.
• Application:
• Interchange lighting and rural intersections due to the ability to reduce glare.
• Use in applications where pedestrians are present. Provides more vertical illuminance than Full Cutoff luminaires.
• Lamp rating should be less than 3200 lumens.
• The cutoff design is where the luminaire light distribution is less than 25,000 lm at an angle of 90° above nadir (vertical axis) and 100,000 lm at a vertical angle of 80° above nadir.

 (C) Semi Cutoff (S) (Medium Beam Angle):

• A luminaire light distribution is designated as Semi cutoff (S) when Less than 5% Intensity at or above horizontal (90° above nadir) and Less than 20% of lamp lumens at or above 80°.
• The direction of maximum intensity may vary but should be below 75º.
• Benefits:
• High-angle light accents taller vertical surfaces such as buildings. Most light is still directed downward.
• Limitations:
• Little control of light at property line.
• Potential for increased glare when using high wattage luminaries. Typically directs more light into the sky than cutoff.
• Application:
• Used for standard road lighting. Adequate glare control is obtained with reasonable spacing.
• The principal advantage of the semi-cutoff system is a greater flexibility in sitting.
• Use in pedestrian areas. If using in residential areas, provide with house side shields to minimize light trespass. Lamp rating should be less than 3200 lumens.
• For the semi-cutoff design, the luminous flux numbers become 50,000 lm for 90° above nadir and 200,000 lm at a vertical angle of 80° above nadir.
• Semi-cutoff fixtures create broad cones of light that permit wide spacing between poles. But such fixtures create harsh glare and send some light directly into the sky.

(D) Non Cutoff (N) (Higher Beam Angle):

• A luminaries light distribution is designated as Non Cutoff (N) when Emit light into all directions.
• No limitations on light distribution at any angle.
• There is considerable output near the horizontal plane.
• Benefits:
• Uniform luminous surfaces such as internally illuminated signs or globes. Wattage should be limited. Suitable for sports lighting, facade, landscape or other applications where luminaires are tilted due to limitations in pole or fixture locations
• Limitations:
• Location and aiming are critical. Most likely of all categories to produce offensive brightness and sky glow.
• Application:
• Used in areas with a lot of background light. Non-cutoff luminaries shall not be used at lower mounting heights because of glare.
• Use for decorative applications only. Lamp rating should be less than 3200 lumens.
• “Full cut off” fixtures must be installed properly, so that the bottom of the fixture is level with the ground.
• “Fully Shielded” fixtures do not allow any light to be emitted above the lowest light emitting
• part, but do not restrict light output in the “glare” zone, 90-80 degrees below horizontal.

  (3) Fixtures Distributions (Optical System):

• The Illuminating Engineering Society classified series of Fixture distribution patterns as Types I, II, III, IV, and V.

(A) Type I (Two-way):

• The lateral distribution having a preferred lateral width of 15 degrees in the cone of maximum Lumen.
• Illumination Pattern: Narrow, symmetric luminance pattern.
• Fixture Location: This type is generally applicable to a luminaire location near the center of a roadway where the mounting height is approximately equal to the roadway width.
• Type of Road: The luminaire is placed on the side of the street or edge of the area to be lighted. Most 1or 2 Lane Road

(B) Type II (Two Way) :

• Light distributions have a preferred lateral width of 25 degrees.
• Illumination Pattern: Slightly wider illuminance pattern than Type I.
• Fixture Location: They are generally applicable to luminaires located at or near the side of relatively narrow roadways, where the width of the roadway does not exceed 1.75 times the designed mounting height.
• Type of Road: The luminaire is placed on the side of the street or edge of the area to be lighted. It produces a long, narrow, oval-shaped lighted area which is usually applicable to narrower streets.

(C) Type III (Bat Wing) :

• Type III light distributions have a preferred lateral width of 40 degrees.
• Illumination Pattern: It produces an oval-shaped lighted
• Fixture Location: This distribution is intended for luminaires mounted at or near the side of medium width roadways, where the width of the roadway does not exceed 2.75 times the mounting height.
• Type of Road: The luminaire is placed on the side of the street or edge of area to medium width streets.

(D) Type IV (Forward throw “Asymmetric”):

• Type IV light distributions have a preferred lateral width of 60 degrees.
• Illumination Pattern: Widest luminance pattern.
• Fixture Location: This distribution is intended for side-of-road mounting and is generally used on wide roadways where the roadway width does not exceed 3.7 times the mounting height.
• Type of Road: very wide roadway (4 to 6 Lane)
• Applications: Type IV often use at perimeters where Spill Light is required and there is no place to add Pole.

(E) Type V:

• Type V light distributions have a circular symmetry of candlepower that is essentially the same at all lateral angles.
• Illumination Pattern: It produces a circular, wider lighted area and is usually applicable to wide streets.
• Fixture Location: The luminaries are mounting at or near center of roadways, center islands of parkway, and intersections.
• Type of Road: very wide roadway (4 to 6 Lane)
• Applications: Type V often applies to high-mast lighting.

GUIDE FOR LUMINAIRE LATERAL LIGHT TYPE AND PLACEMENT
Pole Arrangement	Road Width	Type of Distribution
One Side or Staggered	up to 1.5 x Mounting Height	Types II-III-IV
Staggered or Opposite	Beyond 1.5 x Mounting Height	Types III & IV
Center of the Roadway Mounting	up to 2 x Mounting Height	Type I

 

Type of Classification
AREA CLASSIFICATION	CUTOFF TYPE
Commercial	Full Cutoff or Semi Cutoff
Intermediate	Full Cutoff or Semi Cutoff
Residential	Full Cutoff

 

THE SELECTION OF LUMINAIRE MOUNTING HEIGHTS
Lamp Lumens	Mounting Height
≤20,000 Lumen	≤35 Foot
20,000 To 45,000 Lumen	35 To 45 Foot
45,000 To 90,000 Lumen	45 To 60 Foot

 

Type of LED Luminaries	Type of Road	Lamp mounting height from the floor level (Meters)	Minimum Illumination Level (Lux) at centre of road	Color of Illumination
250-260W		Above 18	(20 To 22)	5000K-6500K
190W	A1	Between 11 To 15	(20 To 22)	5000K-6500K
140-170W	A1	Between 9 To 15	(18 To 20)	5000K-6500K
90-120W	A2/B1	07 To 11	(15 To 18)	4300K-5600K
70-120W	A2/B1	07- To 11	(15 To 18)	4300K-5600K
70-120W	B1/B2	06 To 09	(15 To 18)	4300K-5600K
70-50W	B1/B2/C1	7 To 9	(12 To 15)	4300K-5600K
45-50W	B1/B2/C1	5 To 7	(12 To 15)	4300K-5600K
25-30W	B1/B2/C1	5 To 7	(10 To 12)	4300K-5600K

 

Relationship between mounting height and spacing
Mounting Height	Width of road	6 Meter to 7 Meter		9 Meter to 10.5 Meter		12 Meter to 14 Meter
	Pole  arrangement	Cut-off Type	Semi Cutoff Type	Cut-off Type	Semi Cutoff Type	Cut-off Type	Semi Cutoff Type
8 Meter	Single side	24	28	–	–	–	–
	Staggered	24	28	–	–	–	–
	Opposite	–	–	28	28	–	–
10 Meter	Single side	30	30	–	–	–	–
	Staggered	35	35	30	35	–	–
	Opposite	–	–	35	40	30	35
12 Meter	Single side	42	48	36	42	–	–
	Staggered	–	–	36	42	36	42
	Opposite	–	–	42	48	42	48

 

GUIDE FOR LUMINAIRE LATERAL LIGHT TYPE AND PLACEMENT
SIDE OF THE ROADWAY MOUNTING			CENTER OF THE ROADWAY MOUNTING
One Side or Staggered	Staggered or Opposite	Local Street Intersection	Single Roadway	Twin Roadways (Median Mounting)	Local Street Intersections
Road Width up to 1.5 x Mounting Height	Road Width beyond1.5 x Mounting Height	Road Width up to 1.5x Mounting Height	Road Width up to 2x Mounting Height	Road Width up to 1.5x Mounting Height (each pavement)	Width up to 2.0x Mounting Height
Types	Types	Type	Type	Types	Types
II, III, IV	III & IV	II (4-way)	I	II & III	I (4-way) & V

 

How to Design efficient Street lighting-(Part-2)

(2) Proper Placement of Pole:

(A) Setback

• Set back is the horizontal distance between the face of a light pole and the edge of traveled way.
• Placing luminaries too close to a vertical surface results in hotspots at its base.
• A setback of 3 foot to 4 foot works well for many applications.
• Light from luminaires at extremely short setbacks grazes the surface and enhances its texture.
• Light from luminaries at Long setbacks (Luminaries too far from a vertical surface) cause shadows at low levels.
• Longer setbacks may be required for taller surfaces.
• Scallops between fixtures become more noticeable as setback increases.
• As setback (or spacing) distance increases, Light levels and uniformity decrease.

Set Back (BS 5489)
Design Speed	Pole Set Back
50 Km/Hr	0.8 Meter
80 Km/Hr	1 Meter
100 Km/Hr	1.5 Meter
120 Km/Hr	1.5 Meter

(B) Overhang

• Overhang is the horizontal distance between the center of a luminaries mounted on a bracket (Nadir) and the adjacent edge of a carriage way or traveled way.
• In general, overhang should not exceed one fourth of the mounting height to avoid reduced visibility of curbs, obstacles, and footpaths.

(C) Outreach

• Outreach is the horizontal distance between the center of the column and the center of the luminaries and is usually determined for architectural aesthetic considerations.

(D) Pole Boom(Arm) Length:

• The use of an arm places the light source closer to the traveled way while allowing the pole to be located further from the edge of the traveled way.
• Depending on the application, Pole arms may be single and/or double mast arms or davit arms at the top of the pole.
• There are several different arm lengths and styles of arms that are used.
• Arm Type:
• Type A bracket an arm has a single member arm. It is used when the Arm length is less than 3.5 Meter.
• Type B bracket arm has a two member truss arm design. Type B arms are used when the Arm length is more than 3.5 Meter.
• Arm Lengths:
• The length of the bracket arm is dependent upon a street width, pole location in relation to the curb and the presence of a median.
• Type A (Single member bracket) arms are available in 2 Meter and 2.5 Meter lengths.
• Type B (Twin member bracket) arms are available in 3.5 Meter, 4 Meter and 5 Meter Lengths.
• Pole Height is 10 Meter: On typical streets that are 12 Meter’ wide from curb to curb, either a 2 Meter or 2.5 Meter arm is used. Depending on whether the pole is located behind the sidewalk or in the grass parkway between the sidewalk and the curb, the arm length may need to be increased to 4 Meter.
• Pole Height is 13 Meter: On an undivided street, generally Meter, 2.5 Meter or 4 Meter arms are used.
• Pole Height is 13 Meter: divided Street, typically have a 8 Meter wide center median to divide opposing lanes of traffic. On streets where the light poles are installed in a raised median, two 4 Meter arms oriented 180° apart are used.

(E) Boom Tilt Angle (Boom Angle)

• When the angle of tilt is larger, a uniformity ratio is increasing. Otherwise discomfort glare is increasing because strong light comes into driver’s eyes. So the angle of tilt shall be kept from 15° to 30°.

Tilt Angle
Pole Height	Arm Length	Arm Tile Angle
6 Meter	0.5 Meter	5°,10°,15°
8 Meter	1 Meter	5°,10°,15°
10 Meter	1.5 Meter	5°,10°,15°
>=12 Meter	2 Meter	5°,10°,15°

(F) Pole Height:

• Light poles for conventional highway lighting applications support luminaire mounting heights ranging from approximately 30 ft to 50 ft (9.1 m to 15.2 m).
• Light towers for high-mast lighting applications generally range from 80 ft to 160 ft (24.4 m to 48.8 m) and are designed in multiple sections.
• Weathering steel is a common material choice for light towers.
• Ornamental light Poles used for local streets generally range in height for 8 ft to 15 ft (2.4 m to 4.5 m).

Pole Height	Application
< 6 Meter	Majority of side streets or alleys, Public gardens and parking Area to make people feel safe
8 Meter	Urban traffic route , the multiplicity of road junctions
10 Meter	Urban traffic routes
12 Meter	Heavily used routes
18 Meter	High mast lighting poles shall be installed at large-scale area such as airports, dockyards, large industrial areas, sports areas and road Intersections.

 (G) Poles distance from Curb (Offset):

• The lighting poles should not be installed very close to the pavement edge, because the capacity of the roadway is decreased and the free movement of traffic is obstructed.
• For roads with raised curbs (as in urban roads) =Min. 0.3 meter and desirable 0.6 meter from the edge of raised curb.
• For roads without raised curbs (as in rural roads)=Min. 1.5 meter from the edge of the carriageway, subject to min. 5.0 meter from the center line of the carriageway.
• Height and overhang of mounting
• The glare on eyes from the mounted lights decreases with increases in the height of mounting. Usually, mounting height range from 6 to 10m.
• Overhangs on the lighting poles would keep the poles away from the pavement edges, but still allow the lamp to be held above the curb or towards the pavements.

 (H) Pole to Pole Spacing

• Spacing is the distance, measured along the center line of the road, between successive luminaries in an installation.
• To preserve longitudinal uniformity, the space height ratio should generally be greater than 3.
• Placing luminaries too far apart creates scallops at the base of the surface.
• Spacing distances that are equal to 3 to 4 times the setback work well for many applications.
• Placing luminaries closer together eliminates scallops.
• Uniformity and light levels increase as spacing (or setback) distances decrease.
• Spacing of luminaires normally does not exceed five to six mounting heights.
• The span must not be more than 45 meters and for an average of 20-30 meters.

Lighting Pole details as per Road
Road	Road Width (Meter)	Pole Arrangement	Lamp (Watts)	Pole to Pole Spacing (Meters)	Mounting Height, (Meters)	Arm Length, (Meters)
Expressway	10	Twin Central	250	25 To 35	12	1.5
	15		250	20 To 35	12	3.0
	20	Opposite	250	20 To 45	12	1.5
	25		250	20 To 40	12	1.5
	30		250	20 To 30	12	1.5
	36		250	20 To 25	12	1.5
	40		250	20 To 22	12	1.5
Major	10	One-side	250	10 To 40	10	1.5
	15		250	10 To 45	12	3.0
	10	Twin Central	150	20 To 37	10	1.5
	15		250	20 To 43	12	3.0
	20	Opposite	150	20 To 40	10	3.0
	25		250	20 To 45	10	1.5
	30		250	20 To 45	10	1.5
	36		250	20 To 45	12	3.0
	40		250	20 To 45	2	3.0
Collector	10	One-side	150	10 To 40	10	1.5
	15		250	10 To 50	12	3.0
	10	Twin Central	150	20 To 40	10	1.5
	15		150	20 To 37	12	3.0
	20	Opposite	150	20 To 47	10	1.5
	25		250	20 To 48	10	1.5
Rural Highway	8	One-side	150	10 To 38	8	1.5
	10		150	10 To 37	8	3.0
	15		150	15 To 38	10	3.0
	10	Twin Central	150	20 To 45	10	3.0
	15		150	20 To 39	12	3.0
	20					1.5
Minor	4	One-side	70	10 To 40	8	1.5
	6		70	10 To 40	8	1.5
	8		70	10 To 40	8	1.5
	10		70	10 To 39	8	1.5
	10	Twin Central	70	20 To 35	8	1.5
	15	Staggered	70	10 To 20	8	1.5
	15	Opposite	70	20 To 40	8	1.5

 

Illumination Level
Classification	Average Illumination (lux)	Ratio Minimum to average illumination
Class A1	30	0.4
Class A2	15	0.4
Class B1	8	0.3
Class B2	4	0.3

 

Relationship between Mounting Height and Spacing of Fixtures
Pole Arrangement	Cut-off type		Semi cutoff type
	Height	Spacing	Height	Spacing
Single side	>=0.7 X Width of Road	<=3 X Fixture Mounting Height	>=0.8 X Width of Road	<=3.5 X Fixture Mounting Height
Both Side Staggered	>=1.5 X Width of Road	<=3.5 X Fixture Mounting Height	>=1.7 X Width of Road	<=4 X Fixture Mounting Height
Both Side Opposite	>=0.5 X Width of Road	<=3 X Fixture Mounting Height	>=0.6 X Width of Road	<=3.5 X Fixture Mounting Height
Twin central	>=0.7 X Width of Road	<=3.5 X Fixture Mounting Height	>=0.8 X Width of Road	<=4 X Fixture Mounting Height

 

Pole to Pole Distance vs Lux Level
Pole Height	Lamp	Pole to Pole Distance	Max. Illumination (Lux)	Average (Lux)
4 Meter	15 watt	12 to 18 Meter	25	18
5 Meter	18 watt	14 to 20 Meter	30	18
6 Meter	30 watt	18 to 24 Meter	32	20
7 Meter	50 watt	21 to 28 Meter	32	20
8 Meter	100 watt	24 to 32 Meter	40	22
9 Meter	110 watt	27 to 35 Meter	34	20
10 Meter	140 watt	30 to 40 Meter	35	22
12 Meter	180 watt	30 to 40 Meter	33	23
14 Meter	200 watt	30 to 40 Meter	30	21

 

Lux Vs Mounting Height
Fixtures (Lux)	Mounting Height
3000 to 10000 Lux	6 to 7 Meter
10000 to 20000 Lux	7 to  9 Meter
More than 20000 Lux	More than 9 Meter

 

Road	Road Type	Type of Pole positions	Individual Carriageway Width (Meter)	Central Verge (Meter)	Pole Height above Ground (Meter)	Maximum Pole to Pole Spacing (Meter)	Clearance from Road Edge (Meter)	Bracket Length (Meter)	Tilt Angle	Lighting Specifications	Lamp (Watt)
A1	Dual Carriage	Central Verge	10	1.2	12	40	0.6	1 meter	10°	35 lux /0.4/ 0.33	HP SV 400W
A1	Dual Carriage	Central Verge	11	1.2	12	40	0.6	1 meter	10°	35 lux /0.4/ 0.33	HP SV 400W
A1	Dual Carriage	Central Verge	12	1.2	12	40	0.6	1 meter	10°	35 lux /0.4/ 0.33	HP SV 400W
A1	Dual Carriage	Central Verge	14	1.2	12	40	0.6	1 meter	10°	35 lux /0.4/ 0.33	HP SV 400W
A1	Dual Carriage	Central Verge	16	1.2	12	40	0.6	1 meter	10°	35 lux /0.4/ 0.33	HP SV 400W
A1	Single Carriage	Opposite	12	0	12	35	0.6	1 meter	10°	35 lux /0.4/ 0.33	HP SV 250W
A1	Single Carriage	Opposite	14.5	0	12	35	0.6	1 meter	10°	35 lux /0.4/ 0.33	HP SV 250W
A1	Single Carriage	Opposite	16	0	12	40	0.6	Around one meter	10°	35 lux /0.4/ 0.33	HP SV 400W
A1	Single Carriage	Opposite	18	0	12	40	0.6	1 meter	10°	35 lux /0.4/ 0.33	HP SV 400W
A1	Single Carriage	Opposite	21	0	12	40	0.6	1 meter	10°	35 lux /0.4/ 0.33	HP SV 400W
	Single Carriage	Opposite	25	0	12	40	0.6	1 meter	10°	35 lux /0.4/ 0.33	HP SV 400W
A1	Single Carriage	Opposite	31	0	12	40	0.6	1 meter	10°	35 lux/ 0.4/ 0.33	HP SV 400W
A2	Single Carriage	Single Sided	10		11	30	0.6	< 1.0 meter	10°	25 lux /0.4/ 0.33	HP SV 250W
A2	Single Carriage	Single Sided	9		11	30	0.6	< 0.5 meter	10°	25 lux /0.4/ 0.33	HP SV 250W
A2	Single Carriage	Single Sided	7		11	30	0.6	< 0.5 meter	10°	25 lux /0.4/ 0.33	HP SV 250W
A2	Single Carriage	Single Sided	7		11	30	0.6	< 0.5 meter	10°	25lux /0.4/ 0.33	HP SV 250W
A3	Single Carriage	Single Sided	7		8	20	0.6	< 0.5 meter	10°	20lux /0.4	HP SV 150W
Pedestrian Pathway	Single Carriage	Single Sided	3m-6m		7.5	20-25	0.6	<0.5 meter	10°	20 lux /0.4	HP SV 150W

 

Poles (Meter)	Top Dia (mm)	Bottom Dia (mm)	Thickness (mm)	Base plate (mm)	Single Arm Bracket (mm)	Double Arm Bracket (mm)
3	70	130	3	200x200x12	1000	NA
3	70	130	3	200x200x12	NA	1000
4	70	130	3	200x200x12	1000	NA
4	70	130	3	200x200x12	NA	1000
4	70	130	3	200x200x12	1000	NA
5	70	130	3	200x200x12	NA	1000
5	70	130	3	200x200x12	1000	NA
6	70	130	3	200x200x12	NA	1000
6	70	130	3	200x200x12	1000	NA
7	70	135	3	225x225x16	1000	NA
7	70	135	3	225x225x16	NA	1000
8	70	135	3	225x225x16	1000	NA
8	70	135	3	225x225x16	NA	1000
9	70	155	3	260x260x16	1000	NA
9	70	155	3	260x260x16	NA	1000
9	70	175	3	275x275x16	1000	NA
9	70	175	3	275x275x16	NA	1000
10	70	175	3	275x275x16	1000	NA
10	70	175	3	275x275x16	NA	1000
10	70	200	3	290x290x16	1000	NA
10	70	200	3	290x290x16	NA	1000
11	70	210	3	320x320x20	1000	NA
11	70	210	3	320x320x20	NA	1000
12	70	230	3	325x325x20	1000	NA
12	70	230	3	325x325x20	NA	1000

 

Recommended Levels of Illumination (BIS 1981) (IS 1944)
Type of Road	Road Characteristics	Road Width (Meter)	Average Level of Illumination on Road Surface in Lux	Ratio of Minimum/Average Illumination	Ratio of Minimum/Max Illumination	Type of Luminaire Preferred	Luminas Mounting Height
A-1	Important traffic routes carrying fast traffic	>10.5,12,14,16,18,20,30	30	0.4	33	Cutoff	9 To 10 Meter
A-2	Main roads carrying mixed traffic like city main roads/streets, arterial roads, throughways	> 7 m up to 10 m	15	0.4	33	Cutoff	9 To 10 Meter
B-1	Secondary roads with considerable traffic like local traffic routes, shopping streets	< 7m Colony Roads	8	0.3	20	Cutoff or semi-cutoff	7.5 To 9 Meter
B-2	Secondary roads with light traffic	4m,5m, 6m	4	0.3	20	Cutoff or semi-cutoff	7.5 To 9 Meter