2017
Lighting Scheme Design
Submitted By:
Qania Akram(EE-007),
Hamna Saghir(EE-209),
Komal Fareed (EE-210),
Sameeha Arif(EE-219)
Submitted To:
Miss Ayesha Saeed
Complex Engineering Problem Electrical Power System Distribution (EE-359)
Department of Electrical Engineering NED University of Engineering and Technology
TABLE OF CONTENTS
PROJECT TASK ................................................................................................................. 2
ABSTRACT ......................................................................................................................... 2
PROCEDURE
Making Floor plan ....................................................................................... 2
Designing Lighting Scheme .................................................................................... 3
Lighting terminologies .......................................................................................... 3
Steps for lighting designs ................................................................................... 5
Dialux evo 8.1 ..................................................................................................... 6
Luminaire parts list .............................................................................................. 8
Lighting Design on Dialux of conference room ............................................... 8
Calculation for luminaire .................................................................................... 9
Calculating Total load
For heavy loads ................................................................................................. 10
For lighting loads ............................................................................................... 12
Cable Sizing
Basic Information ............................................................................................... 12
Voltage Drop Consideration ........................................................................... 13
Ampacity Consideration ................................................................................... 13
Calculations.......................................................................................................... 14
Circuit Breaker Sizing ................................................................................ 16
ENERGY EFFICIENT SYSTEM ............................................................................ 16
SUITABLE BUS BAR SCHEME ........................................................................... 17
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Complex Engineering Problem Electrical Power System Distribution (EE-359)
Department of Electrical Engineering NED University of Engineering and Technology
PROJECT TASK:
We were given the task to propose the efficient and cost-effective lighting scheme of any of
the floor of any commercial building and select luminaries according to it. Then calculate the
total load of the building and select appropriate cables (or busways) and breakers according
to the ampere rating as per standard operating procedures keeping all factors in
consideration. We also had to propose any other measures to improve energy efficiency in
our proposed plan, also to select the best utilized bus bar scheme for power distribution panel
in substation of the selected commercial building.
ABSTRACT:
This report comprises of lighting scheme design of a commercial office building. Good lighting
design is an essential element of the interior design scheme of every single building. We have
considered only first floor of our multi-storey building and the cable from main Distribution
board to our floor will be on a perforated cable tray, it will be wall mounted. During lighting
the type of room has been kept in mind as each room has its different lux level which has to
be maintained. After lighting, the total load of the floor has been calculated and size of the
cable has been proposed on the basis of load current in order to distribute that load on
different circuit breakers, however, Circuit breaker size is proposed according to over current
rating of each cable. At last, the best utilized bus bar scheme for power distribution panel in
substation is selected also some measures are proposed to improve energy efficiency of our
proposed plan.
PROCEDURE:
✓ Making floor plan:
First, we drew the 2D floor layout of the office building using AutoCAD with proper labelling
& dimensions in ft.
Then we imported our AutoCAD dwg file into Dialux evo 8.1. and adjust its dimensions in
meters (i.e. length= 21.6m, width= 33.675m and height=3m). After indoor and outer contour
of the floor we got its 3D view.
After that some furniture and apertures are placed in the office plan with their suitable
dimensions and position. Following is the 2D view of our floor plan on Dialux.
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Complex Engineering Problem Electrical Power System Distribution (EE-359)
Department of Electrical Engineering NED University of Engineering and Technology
Figure (1): 2D view of first floor
✓ Designing Lighting Scheme:
Lighting is an essential provision for office. Good lighting helps to see and to recognize
hazards. It can reduce visual strain and discomfort. Poor lighting may affect employees'
performance and health as poor visibility increases the chances of errors being made. It also
means that people work slower. We have proposed a good lighting scheme design for the
office according to international standards of commission. For office we proposed a direct
lighting scheme design in which light is directly made to fall on working plane. Since the office
is the area where business is conducted therefore, a cool White colour lights can help keep
employees attentive, focused, and productive throughout the day. For this design the selected
luminaries have following specifications.
LIGHTING TERMINOLOGIES
LUX:
It is the SI unit of illuminance.
One lux is the amount of illumination provided when one lumen is evenly distributed over an
area of one square meter.
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Complex Engineering Problem Electrical Power System Distribution (EE-359)
Department of Electrical Engineering NED University of Engineering and Technology
ILLUMINANCE:
The total amount of luminous flux that incident on per unit of surface area.
Its SI unit is measured in LUX or (lumens per square meter).
∅
𝑬=
𝑺
Where,
E = illuminance
Ø = luminous flux
S = area of surface
LUMINANCE:
It is the product of luminous flux and the surface. It is the luminous intensity (brightness) that the
humans perceive from the light that is reflected from the surface being illuminated.
Its SI unit is measured in (cd/square meter)
𝑰
𝑳 =
𝑺
Where,
L = luminance
I = luminous intensity
S = area of surface
LUMINOUS FLUX:
Luminous flux is the energy that is being emitted from a light source. It is the luminous intensity
(brightness) from a light source.
Its SI unit is measured in LUMEN (lm).
∅=𝑰∗𝜷
Where,
Ø = luminous flux
Β = steradian angle
I = luminous intensity
LUMINOUS EMITTANCE:
The amount of luminous flux per unit area emitted from a surface.
LUMINOUS EFFICACY:
It is the ratio of luminous flux to power. It is the measure of how well a light source produces
visible light.
Its unit is lumens per watt.
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Complex Engineering Problem Electrical Power System Distribution (EE-359)
Department of Electrical Engineering NED University of Engineering and Technology
LUMINAIRE EFFICACY:
A luminaire is a light fixture; light fitting is any electrical device that contains an electric lamp
that is used to provide artificial light or illumination.
Luminaire efficacy is the output light emitted from entire luminaire divided by the total power
consumed by the lamps. Its unit is lumens per watt.
LIGHT OUTPUT RATIO (LOR):
It is the ratio of the luminous flux of the luminaire to the lumens of the lamps used. It shows the
amount of light gets lost inside the luminaire. It can be calculated by dividing the total light
output from luminaire by total lamp output. Both in lumens.
STEPS FOR LIGHTING DESIGN:
1. Find out the standard lux level of the room.
2. Calculate the lighting design factors which include utilization factor, mounting height
and maintenance factor.
3. Calculate room index.
4. Then select the type of lighting or luminary on the basis of the type and size of the
room and also efficacy of fixtures.
5. Then after selecting the luminaries, find out the number of fixtures required keeping
the standard lux level in mind.
6. Then after deciding the number of fixtures, compare the total lux level with the
standard lux level that we have used.
FACTORS CONSIDERED DURING LIGHTING DESIGN:
• Lux • Color of surrounding walls
• Area of the room • Uniformity of illumination
• Maintenance factor • Number of fixtures
• Mounting height
LUX LEVELS:
Lux level varies according to the type of building and type of room. Each room has some
specific lux level. Some rooms require higher lux levels some require low so to find out this
which room require how much lux there are various standards that provide standard lux levels
of different rooms. Among them CIBSE standards are the most efficient one.
CIBSE, the chartered institution of building services engineers, acts as a professional entity for
lighting in the UK and provides series of guides about optimum and efficient lighting
requirements for a wide range of areas. Standard of CIBSE for lux in table below.
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Complex Engineering Problem Electrical Power System Distribution (EE-359)
Department of Electrical Engineering NED University of Engineering and Technology
CIBSE standards for LUX level
Distribution& storage
Warehouse/bulk stores 100 lux
Unpacking & sorting 200 lux
Large item stores 100 lux
Packing & dispatch 300 lux
Small item stores 200 lux
Offices
General 500 lux
Computer work stations 350-500 lux
Auditorium 300-500 lux
General
Entrance halls & lobbies 200 lux
Changing rooms & toilets 100-150 lux
Corridors & stairs 100-150 lux
Entrances/ exit 200 lux
Consideration other than Lux Level:
Maintenance factor 0.8
Uniformity Factor 0.6
Wall material/Reflection Roughcast plastering white/
factor 86%
Mounting Height 3m
DIALux EVO 8.1:
DIALUX is a world’s leading lighting design software. DIALux is used for professionally design,
calculate and visualize light more appropriately effectively and efficiently. We can design
single room, offices, whole floors and whole buildings. We have used DIALUX EVO 8.1 for our
lighting design as this version of DIALUX is more efficient it has more options and variety it
provides lighting design of single room, whole floors, whole buildings as well as outdoor
lighting and road lighting. The step by step procedure of lighting design in DIALUX is
explained below.
• Loading the plan of the area for lighting
• Construct the building then by using new room option constructed all the spaces of the
floor
• Draw the necessary windows and doors.
• Place the required furniture or objects in the plan.
• Apply material or color on the floor, wall, furniture & roof.
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Complex Engineering Problem Electrical Power System Distribution (EE-359)
Department of Electrical Engineering NED University of Engineering and Technology
• Select the manufacturer and install manufacturer catalog. The manufacturer that we
have selected is Philips lighting.
• Selecting the luminary on the basis of Space type.
• Selecting no. of luminaries to achieve required lux level according to standards. The
standard that we have follow for efficient, effective and appropriate lighting is CIBSE
standards.
• Running command “entire project calculation”.
• Now verifying the lux of each area with the standard lux of that area.
• Now generate the report that contains the summary of entire project which includes
luminous emittance, lamp luminous flux, luminaire luminous flux, power, luminous
efficacy of every room. It also contains the luminary models and quantity of luminaries
that we have used in our design. It contains 2D view of each room and its respective
isolines that represent the lux level in each corner of the room.
3D VIEW OF FIRST FLOOR:
Figure (2): 3D view of first floor
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Complex Engineering Problem Electrical Power System Distribution (EE-359)
Department of Electrical Engineering NED University of Engineering and Technology
LUMINAIRE PARTS LIST:
Total No. of Luminaires used on First Floor:
The above figure shows the total load been calculated by designing the lighting scheme of the
floor.
LIGHTING DESIGN ON DIALUX OF CONFERENCE ROOM:
3D View:
Figure (3) : 3D View
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Complex Engineering Problem Electrical Power System Distribution (EE-359)
Department of Electrical Engineering NED University of Engineering and Technology
PHOTOMETRIC RESULT:
Figure (4) : Lux Level
LIST OF LUMINAIRES:
CALCULATION FOR NO. OF LUMINAIRE:
𝐸∗𝐴
𝐹𝑠 =
𝑈. 𝐹 ∗ 𝑀. 𝐹
Fs=Total lumens required in area
E= Illuminance or Lux
U.F= Utilization Factor
M.F= Maintenance Factor
For Conference Room,
E= 500lx
U.F= 0.9
Area= 6.65*3.8
M.F= 0.8
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Complex Engineering Problem Electrical Power System Distribution (EE-359)
Department of Electrical Engineering NED University of Engineering and Technology
So,
500 ∗ 6.65 ∗ 3.8
𝐹𝑠 =
0.9 ∗ 0.8
Fs= 17548.611 lumens
n= Fs/F
Fs=Total lumens required in area
F= Lumens of Luminaire
17548.611
𝑛=
2799
n= 6 luminaires
The number of luminaires calculated manually are equal to the luminaires used in the dialux
evo.
✓ Calculating Total Connected Load:
Heavy Loads:
ROOMS TYPES OF LOADS/ Quantity/ Load for each TOTAL POWER
Charger and CCTV 2 7.5 2007.5
batteries Chiller 1 2000
Charger and CCTV 2 7.5 2007.5
batteries Chiller 1 2000
Supervision room Large 1 72 2247
monitoring
screen
Laptop 1 75
Chiller 1 2000
Water 1 100
dispenser
Maintenance and AC 1 4220 5363
control room Laptops 5 5*75
Printer 1 400
CCTV 4 4*7.5
LED 1 138
Recording box 1 200
of CCTV
Workshop Printer 1 400 7615
Desktop 3 3*250
computer
Laptops 6 6*75
Chillers 3 3*2000
CCTV 2 2*7.5
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Complex Engineering Problem Electrical Power System Distribution (EE-359)
Department of Electrical Engineering NED University of Engineering and Technology
Conference room Large projector 1 300 6757.72
1 Chillers 3 3*2000
CCTV 1 7.5
Mic 1 0.22
Speakers 3 3*150
Conference room Medium 1 150 4457.72
2 projector
Chillers 2 2*2000
CCTV 1 7.5
Mic 1 0.22
Speakers 2 2*150
Lobby CCTV 2 2*7.5 4153
Chillers 2 2*2000
TV 1 138
Gents toilet Hand dryer 1 1000 1000
Ladies Toilet Hand dryer 1 1000 1000
Corridors Chillers 3 3*2000 6030
CCTV 4 4*7.5
Pantry room Water 2 2*100 9000
dispenser
Coffee maker 1 800
Chiller 2 2*2000
Toaster 2 2*1200
Microwave 2 2*800
oven
Security room Monitoring 5 5*40 4600
screens
Desktop 1 300
computers
Chillers 2 2*2000
Water 1 100
dispenser
UPS room UPS 2 2*525 1050
UPS room 2 UPS 2 2*525 1050
MDB room Chillers 1 2000 2000
MDB room 2 Chillers 1 2000 2000
Podium room Large projector 1 300 600.22
Mic 1 0.22
Speaker 2 2*150
Prayer room Chillers 2 2*2000 4000
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Complex Engineering Problem Electrical Power System Distribution (EE-359)
Department of Electrical Engineering NED University of Engineering and Technology
The total load of the floor is divided in heavy load and lighting load:
TOTAL HEAVY LOAD = 125.85 kW
Lighting Loads:
Room Load Room Load
Charger & Batteries-1 56 Lobby 61
Conference Room-1 178.5 MDB-1 47
Conference Room-2 131.5 MDB-2 47
Corridor 154 Podium 70.5
Female prayer room 61 Security Room 70.5
G.toilet 56 Staff Room 352
G.toilet 1 11.6 Staircase 70
G.toilet 2 11.6 Store room 28
G.toilet 3 11.6 Supervision Room 70.5
Genset Room 94 UPS & Charger-2 56
Kitchen 47 UPS Room-1 47
Ladies toilet 23.2 UPS Room-2 47
Ladies toilet 1 11.6 Workshop 164.5
Ladies toilet 2 11.6 Cleaner Room 47
Total lighting load of the floor will be:
TOTAL LIGHTING LOAD = 2.07kW
So total combined load of our floor is:
TOTAL COMBINED LOAD = 64.993kW
✓ Cable Sizing:
Basic Information:
The following basic cable specification was selected:
Conductor material: Copper
Insulation type: PVC
Number of cores: Four core
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Complex Engineering Problem Electrical Power System Distribution (EE-359)
Department of Electrical Engineering NED University of Engineering and Technology
The following load parameter were selected:
Number of phases: Three phase
Nominal load voltage: 440 V
Full load power factor: 0.85 pu
Full load current: 100.34 A
Voltage Drop Considerations:
The calculation a three phase voltage drop for a 35 mm2 cable is based on the following
equation:
𝒎𝑽
𝑰𝑳 ∗ 𝑳 𝑨 / 𝒎 ∗ √𝟑
𝑽𝒅 =
𝟏𝟎𝟎𝟎
Where
Vd is the calculated voltage drop (V)
I is the full load current = 100.34 A
L is the total cable length = 11m
Rc is the cable ac resistance = 0.884 Ω/km (based on typical values)
Xc is the cable ac reactance = 0.121 Ω/km (based on typical values)
Result
The voltage drop across the 35 mm2 cable is Vd = 4.57 V (or equivalently 1.04 % of nominal
voltage)
Ampacity Considerations:
The cable is installed under the following conditions:
Ambient Temperature: 30 °C
No. of grouped cables: 3 cables
Given this cable installation, the derating factors are as follows:
Ambient Temperature: 1.0
Grouping derating: 0.82
Total derating factor: 0.82
Since, the cable is not undergrounded, so, Soil resistivity factor and depth factor are
neglected.
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Complex Engineering Problem Electrical Power System Distribution (EE-359)
Department of Electrical Engineering NED University of Engineering and Technology
Result
For the full load current: 100.34 A
Minimum Single Core cable size is: 35.0 mm2
Cable base ampacity: 121.95 A
Installed / derated ampacity: 100.34 A
The above factors were referred from the ‘Low Voltage Cables, Pakistan Cables’.
Temperature Factor:
Grouping Factor:
Calculations:
𝑷 = √𝟑𝑽𝑰𝒄𝒐𝒔𝜽
65𝑘𝑊
𝐼=
√3 ∗ 440 ∗ 0.85
IL = 100.34 A
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Complex Engineering Problem Electrical Power System Distribution (EE-359)
Department of Electrical Engineering NED University of Engineering and Technology
𝑰𝑳
𝑰𝒄𝒄𝒄 =
𝑫𝒇
𝟏𝟎𝟎. 𝟑𝟒
𝑰𝒄𝒄𝒄 = = 𝟏𝟐𝟏. 𝟗𝟓𝑨
𝟎. 𝟖𝟐
Selecting the cable according to the current rating:
VOLTAGE DROP:
𝒎𝑽
𝑰𝑳 ∗ 𝑳 𝑨 / 𝒎 ∗ √𝟑
𝑽𝒅 =
𝟏𝟎𝟎𝟎
100.34 ∗ 11 ∗ 2.4 ∗ √3
𝑉𝑑 = = 4.57𝑉
1000
𝟒. 𝟓𝟕
% 𝑽𝒅 = 𝐱 𝟏𝟎𝟎 = 𝟏. 𝟎𝟒%
𝟒𝟒𝟎
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Complex Engineering Problem Electrical Power System Distribution (EE-359)
Department of Electrical Engineering NED University of Engineering and Technology
✓ Circuit Breaker Sizing:
Proposed size of circuit breaker
Non Continuous load
Power 20.69kW
Voltage 440V
Power Factor 0.85
Current 31.94A
Continuous load
Power 44.3kW
Voltage 440V
Power Factor 0.85
Current 68.3A
OCPD = 100% of Non-cont. + 125% Cont.load
= 100% x 31.94A + 125%( 68.3)
OCPD = 117.3A
ENERGY EFFICIENT SYSTEM:
1. LED Lights over CFLs:
We can use LED Lights instead of using CFLs (Compact Fluorescent Light), as LED bulbs produce
a unique color of light that is very similar to the natural light of the sun. LEDs reach their peak
brightness as soon as they are turned on and do not require a warmup phase like
incandescent or florescent bulbs.
Also, the average CFL bulb can shine bright for up to 8,000 hours of use. But it can hold a
candle to LED bulbs, which offer as much as 25,000 hours of light per bulb. LED bulbs are
affordable but tend to cost more than CFL bulbs because of how long LED bulbs last, and
because of that reason they pay for themselves over time.
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Complex Engineering Problem Electrical Power System Distribution (EE-359)
Department of Electrical Engineering NED University of Engineering and Technology
2. BlackOut Window Film:
We can cover the windows with blackout window films, which will block the direct sunlight
rays, and hence, heating effect will reduce, due to which, we can cut down the usage cooling
loads.
3. Controller and Sensor Based Lights:
We can introduce a sensor based system, which will save our energy to a drastic level. The
lights will switch on, only when someone walks in the corridor and a motion is detected, and
switches off when no motion is detected.
Also, we can introduce a key card system in rooms, which will operate when card is inserted in
the room lock, which will indicate that a person is inside the room, and as soon as the person
leaves taking off the card, the lights will switch off.
4. Temperature Sensors:
We can use temperature sensors, which will take record temperature and if the temperature
rises from 20℃, the chillers will switch on, otherwise, it will be switched off. This can save both,
energy and cost, to a great extent.
SUITABLE BUS BAR SCHEME:
A substation bus scheme is the arrangement of overhead bus bar and associated switching
equipment (circuit breakers and isolators) in a substation. The operational flexibility and
reliability of the substation greatly depends upon the bus scheme.
The first requirement of any substation design is to avoid a total shutdown of the substation for
the purpose of maintenance, or due to fault somewhere out on the line. A total shutdown of the
substation means complete shutdown of all the lines connected to the substation.
There are six common substation bus schemes:
1. Single Bus
2. Main Bus and Transfer Bus
3. Double Bus Double Breaker
4. Double Bus Single Breaker
5. Ring Bus
6. Breaker and Half
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Complex Engineering Problem Electrical Power System Distribution (EE-359)
Department of Electrical Engineering NED University of Engineering and Technology
The best suitable ring bus scheme for our office is ‘Ring Bus Scheme’. The reasons are as
follow:
• In the ring bus configuration, as the name implies, the circuit breakers are connected to
form a ring, with isolators on both sides of each breaker. Circuits terminate between
the breakers and each circuit is fed from both sides.
• This scheme has good operational flexibility and high reliability, any of the circuit
breakers can be opened and isolated for maintenance without interruption of service.
• If a fault occurs in this configuration, it is isolated by tripping a breaker on both sides
of the circuit. By tripping two breakers, only the faulted circuit is isolated while all the
other circuits remain in service.
• Ring Bus is suitable to handle 6 circuits at a time, and since we have 3 circuits, this bus
bar scheme becomes suitable.
• Ring Bus covers fairly low area when compared with DBDB, Breaker and a half or
DBSB.
• It is cheap as compared to DBDB and DBSB.
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