Input Parameters
meters
meters
0.1-1.0
0.1-1.0
Formula: Al = (E × w × d) / (cu × mf)
Where: E = Required Lux, w = Road width, d = Pole distance,
cu = Coefficient of utilization, mf = Maintenance factor
Where: E = Required Lux, w = Road width, d = Pole distance,
cu = Coefficient of utilization, mf = Maintenance factor
Calculation Results
Required Illumination (E)
6.46
lux
Average Lumens Needed (Al)
8,663
lumens
Recommended Lamp
250W
SUITABLE
Actual Illumination
8.57
lux
Comparison
+32.7%
ADEQUATE
Notes
• Recommended illumination levels vary based on traffic density and road classification
• Standard lamp lumen values: 125W = 5,400 lm, 250W = 11,500 lm, 400W = 20,500 lm
• Voltage drop should not exceed 5% for 230V systems (15% maximum in extreme cases)
Pole Spacing Parameters
lumens
lux
meters
meters
0.1-1.0
0.1-1.0
0.1-1.0
Formula: S = (LL × CU × LLD × LDD) / (E × W)
Where: S = Luminaries Spacing, LL = Lamp Lumens,
CU = Coefficient of Utilization, LLD = Lumen Depreciation Factor,
LDD = Luminaries Dirt Depreciation Factor, E = Lux Level, W = Road Width
Where: S = Luminaries Spacing, LL = Lamp Lumens,
CU = Coefficient of Utilization, LLD = Lumen Depreciation Factor,
LDD = Luminaries Dirt Depreciation Factor, E = Lux Level, W = Road Width
Spacing Results
Calculated Spacing
23.0
meters
Spacing in Feet
75.5
feet
Optimal Spacing
20-25
meters
OPTIMAL
Number of Poles per km
43
poles/km
Illumination Time Parameters
factor
hours
lux
Formula: T = (k × t × 1000) / E
Where: T = Allowed Illumination Time, k = Extension Factor,
t = Permissible time at 1000 lux, E = Luminance Level
Where: T = Allowed Illumination Time, k = Extension Factor,
t = Permissible time at 1000 lux, E = Luminance Level
Illumination Time Results
Allowed Illumination Time
1,400
hours
In Days
58.3
days
Lamp Lifespan Comparison
+200%
GOOD
Uniformity Ratio Parameters
Use the 9-point measurement method as described in the standard.
lux
lux
lux
lux
lux
lux
lux
lux
lux
Formula: UR = Eav / Emin
Where: UR = Uniformity Ratio, Eav = Average maintained horizontal luminance,
Emin = Minimum illumination on pavement
Average Lux = [(P1+P3+P7+P9)/16] + [(P2+P6+P8+P4)/8] + [P5/4]
Where: UR = Uniformity Ratio, Eav = Average maintained horizontal luminance,
Emin = Minimum illumination on pavement
Average Lux = [(P1+P3+P7+P9)/16] + [(P2+P6+P8+P4)/8] + [P5/4]
Uniformity Results
Average Illumination (Eav)
7.37
lux
Minimum Illumination (Emin)
6.5
lux
Uniformity Ratio (UR)
1.13
GOOD
Standard Compliance
≤ 3.0
COMPLIES
9-Point Measurement Diagram
Measurement points layout between two street light poles
Pole 1 Pole 2
│ │
├─ P1 ─── P2 ─── P3 ──┼─ P4 ─── P5 ─── P6 ─┤
│ │
├─ P7 ─── P8 ─── P9 ──┴─ Road ────────────┤
│ │
Energy Saving Parameters
hours/day
days/year
$/kWh
units
hours
$/unit
Formula: Running Cost = (Electricity Cost × Wattage × Hours) / 1000
Annual Savings = (Current Wattage - Proposed Wattage) × Hours × Days × Cost × Units / 1000
Annual Savings = (Current Wattage - Proposed Wattage) × Hours × Days × Cost × Units / 1000
Energy Saving Results
Annual Energy Consumption
109,500
kWh
Annual Energy Cost
16,425
$
Proposed Annual Cost
6,570
$
Annual Savings
9,855
$
SAVING
ROI Period
0.5
years