Electrical Design Report Prepared By: addis fisseha

Contents
I. INTRODUCTION: Design Scope.................................................................................................................2
II. Lighting system/illumination of the buildings..........................................................................................2
A -Luminance calculation.........................................................................................................................3
1...........................................................................................................................................................3
2. Ground floor....................................................................................................................................3
. 1st floor plan......................................................................................................................................4
C. Metering and Billing type....................................................................................................................6
III. Power socket outlet system....................................................................................................................6
IV. Telephone/Data outlet system...............................................................................................................7
V. Main Antenna Television Outlet System.................................................................................................7
VI. Power calculation and selection of power cable....................................................................................7
GFMDB................................................................................................................................................8
SDB- 1F................................................................................................................................................8
VIII. Appendix..............................................................................................................................................9
A. Breaker, cabel size and conduit...........................................................................................................9
B. Light fitting and lamps.........................................................................................................................9

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 Electrical Design Report Prepared By: addis fisseha

I. INTRODUCTION: Design Scope

This design scope covers the following areas of electrical provisions for each section of the building
with due attention also given to the sub sections of electrical and low current systems.
The main considerations made while preparing this electrical design are the need to consider almost all
latest requirements of such premises at an international as well as local standard and hence all
electrical/electronic facilities are made part of the final design.
The design consists of lighting system with state of the art lighting technologies from the famous
manufacturer’s products while the aesthetic and architectural finish of the final appearance is also taken
full consideration. The switching and control circuits are selected to comply with future requirements
and modifications that could be thought of by the owner.
The power and socket outlets are so designed to provide safe and reliable power to various appliances
that the customers might require, with due attention also given to the power distribution to sub sections
through Normal Utility Power.
The telephone system is designed such that the owner could make up to date proposal on the type of
facility that is required. For the Telecom and MATV system, separate distribution frames are provided
in each floors to make ease of installation and future management
The Main Antenna Television System, MATV, is also a facility that is designed to accommodate
installation of one or many channels for TV signals to different outlets without loss of signals.
Following are details of each design components by taking in to consideration of the local and
international electrical standards, while every design is to be supplemented with specific technical
specifications, estimated bills of quantities as well as engineering estimate of the materials and labor for
execution of this project. It is the designer’s belief that what has been estimated as cost for this project is
purely engineering estimate.

II. Lighting system/illumination of the buildings

Flush/Recessed Lighting Point For Various Rooms
No Visual Task Average Illumination No Visual Task Average
(Lux) Illumination (Lux)
1 Kitchen 200 13 Gymnasim 400
2 Livig and dining 200 14 Hall 350
3 Bed room 150 15 Bed room 150
4 Corridor/ Lobby 100
5 Car parking 150
6 Terrace 75
7 Toilet 100
8 Store 100
9 Open down 100
10 cafteria 200
11 Conference room 500
12 Office 300

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Electrical Design Report Prepared By: addis fisseha

A -Luminance calculation

The number of fixtures required for a specific lighting installation is calculated with the following
formula.
( l× w )
N=Em × , A=l × w
( Cu ×C m ×φ )
Where Em is the required average illuminance in Lux, A is the floor area to be illuminated ,C m is the
maintenance factor for new installation Cm=1 but it is recommended to take Cm=0.8. φ is the flux emitted
by the lamps in lumen. The utilization coefficient is Cu. It is recommended to take Cu=0.6
(Illuminance value From Disano 1998 catalogue page 302)

From Disano 1998 catalogue page 300.

-The lumen output of 18w linear fluorescent lamp is 1350 lumen.
-The lumen output of 36w linear fluorescent lamp is 3350 lumen.
-The lumen output of 18w compact fluorescent lamp is 1200 lumen.(GX24 d-2)
-The lumen output of 22w compact fluorescent lamp is 1360 lumen.(E27)
-The lumen output of 26w compact fluorescent lamp is 1800 lumen.(GX24 q-3)
-The lumen output of 10w LED fluorescent lamp is 830-920 lumen.(From RZB A5 product
selection guide page 615.
-The lumen output of 18w LED lamp is 800-850 lumen.(From RZB A2 product selection
guide page 395)
-The lumen output of 12.5w LED lamp is 555-660 lumen based on colour
-From Osram the lumen output of 9w E-27 LED lamp is 766 lumen .
-From Osram the lumen output of 7.5w GU-10 LED lamp is 390 lumen .

1.Ground floor
A. Store -100 lux




¿
[ E (lux)×( A)m2 ]

[(O)lum ×U × M ]

E(lux) A(sq.m) O(lum) U M ExA= OxUxM= N=

100 99 3350 0.6 0.8 9900 1608 6.156716 ≈6

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Electrical Design Report Prepared By: addis fisseha

For better arrangment it is better to use 6 ceiling mounted 1x36w fluroscent almps.

B. Shop-200 lux



[ E (lux)×( A)m2 ]
¿ 
[(O)lum ×U × M ]

E(lux) A(sq.m) O(lum) U M ExA= OxUxM= N=

200 17 3600 0.6 0.8 3400 1728 1.967593 ≈1.96

For better arrangment it is better to use 2 LED panel of 36w.

2.First floor
A. Bed room -150 lux




¿
[ E (lux)×( A)m2 ]

[(O)lum ×U × M ]

E(lux) A(sq.m) O(lum) U M ExA= OxUxM= N=

150 20 1200 0.6 0.8 3000 576 5.208333 ≈5

For better arrangment it is better to use 3 wall lights with 18w lamps and 1 chandilier
lights having three lamps of 18w.

2.Second floor

B. Bed room -150 lux





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Electrical Design Report Prepared By: addis fisseha

[ E (lux)×( A)m2 ]
¿ 
[(O)lum ×U × M ]

E(lux) A(sq.m) O(lum) U M ExA= OxUxM= N=

150 20 1200 0.6 0.8 3000 576 5.208333 ≈5

For better arrangment it is better to use 3 wall lights with 18w lamps and 1 chandilier
lights having three lamps of 18w.

For bath room and balcony their area is less than 5 meter squere, so one fitting with 18w CFL
lamp for each of them can be mounted.

SWITCHES: LEGRAND MOSAIC, DECOR/SUNO TYPE, Screw mounting plates and grids,
mechanisms are recommended for the owner to have full right to choose what he/she wants.
Flush boxes, support frames, plates and mechanisms: all compatible to MOSAIC/DECOR design. If
owner’s choice is that.

C. Metering and Billing type

The dwelling is assumed to have its own KWH meter and electrified from Main Distribution Board.

III. Power socket outlet system

SINGLE PHASE, EARTHED SOCKETS

16A/1 P, P+N+E, SHUCKO TYPE OF SOCKET
TWO TYPES: TYPE 1: SINGLE
TYPE 2: DUPLEX
Power considered for each socket is 200w for general purpose outlet, 1500w for water heater, 2500w for
stove and 3000w for ‘injera mitad’
For general purpose outlet the maximum number of outlet per circuit is six
- For socket and lighting system

P
I= , where V =220 v
V
Breaker size for socket outlet 16A & wire size 3x2.5mm2
Breaker size for lighting system 10A & wire size 2x2.5mm2

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Electrical Design Report Prepared By: addis fisseha

IV. Telephone/Data outlet system

3.1 TELEPHONE SOCKET: LEGRAND MOSAIC/DÉCOR/SUNO TYPE ARERECOMENDEDE the
owner has full right to choose what he/she wants are RJ-11 telephone outlet CAT-5E
3.2 TELEPHONE TERMINAL BOX: TYPE MINIMUM OF TWO KNOCKOUTS ON LONGER BOX
SIDES SIZE 300X200X100MM, MINIMUM

V. Main Antenna Television Outlet System

4.1 SOCKET OUTLET:
LEGRAND MOSAIC/DÉCOR/SUNO TYPE ARE RECOMENDEDE
The owner has full right to chose what he/she want
1. TV + FM + SAT SOCKETS
2. TV PASSAGE
3. TV SINGLE WITH MALE
4. TV TERMINAL BOXES:
PULL THROUGH JUNCTION BOXES
TYPE DECOR
MINIMUM OF TWO KNOCK OUTS ON LONGER BOX SIDES
SIZE: 200X200X100 MM, MINIMUM

VI. Power calculation and selection of power cable

- To calculate the current rating for single phase
Ptot =V × I ×cos ( φ )
Where cos ( φ ) is the power factor which is 0.8
Ptot
I=
[ V × cos ( φ ) ]

where V is the voltage rating of single phase=220V

- To calculate the current rating for three phase
Ptot =√ 3 ×V × I × cos ( φ )
Where cos ( φ )is the power factor which is 0.8
[ P max ]
I=
[ √3 × V × cos ( φ ) ]
where V is the voltage rating of three phase=380V
-Cable size rating can be selected from EBCS code or other standards based on the current rating we
have calculated.
VII. Standards and regulations:

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Electrical Design Report Prepared By: addis fisseha

MDB-GF
Ptot =22.23kw, Pmax = Ptot*0.8= 22.23kw * 0.8=17.78kw
[ P max ] 17 .78 kw
I= = = 33.81A
[ √3 × V × cos ( φ ) ] [ √3 ×380 × 0.8 ]
So 50A three phase breaker is selected.
Flush mounting distribution board, GFMDB in Steel enclosure with lockable door, and with phase
Neutral and earth bus-bars 63A/3P rating and cable size of phase/neutral (4x25)mm2 and earthing
conductor of size 1x16 mm2 .

SDB- 1F
Ptot = 12.05kw, Pmax = Ptot.=0.8*12.05kw=9.64 kw
[ Pmax ] 9.64 kw
I= = =18.33A
[ √3 × 380V × cos ( φ ) ] [ 1.73∗380 v × 0.8 ]
So 32A/3p three phase breaker is selected.
Flush mounting sub distribution board, SDB-1F in an enclosure with lockable door, and with phase
neutraland earth bus-bars 50A /3P rating and cable size is 5x6mm2 .

SDB- 2F
Ptot = 12.05kw, Pmax = Ptot.=0.8*12.05kw=9.64 kw
[ Pmax ] 9.64 kw
I= = =18.33A
[ √3 × 380V × cos ( φ ) ] [ 1.73∗380 v × 0.8 ]
So 32A/3p three phase breaker is selected.
Flush mounting sub distribution board, SDB-1F in an enclosure with lockable door, and with phase
neutraland earth bus-bars 50A /3P rating and cable size is 5x6mm2 .

(1) EBCS-10 STANDARD

(2) PHILIPS ISL ILLUMINATION DESIGN DETAILS
(3) ETHIOPIAN BUILDING DESIGN AUTHORITY, EBCA,
(4) ELECTRICAL HANDBOOK
(5) ETHIOPIAN ELECTRIC POWER CORPORATION: RULES AND REGULATIONS

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Electrical Design Report Prepared By: addis fisseha

VIII. Appendix

A. Breaker, cabel size and conduit

1. 2A/1P 3x2.5
2. 6A /1P 3x2.5
3. 10A/P 3x2.5
4. 16A/P 3x2.5
5. 16A/3P 5x2.5 Ø20mm
6. 20A/1P 3x4 Ø32mm
7. 20A/3P 5x4 ”
8. 25A/1P 3x6 ”
9. 25A/3P 5x6 ”
10. 32A/3P 5x10 Ø50mm
11. 40A/3P 5x10 ”
12. 50A/3P 5x10 ”
13. 63A/3P 5x16 ”
14. 80A/3P 3x25/16+1x16 Ø75mm
15. 100A/3P 3x35/16+1x16 ”
16. 125A/3P 3x35/16+1x16 Ø110mm
17. 160A/3P 3x50/25+1x25 ”
18. 200A/3P 3x70/35+1x35 ”
19. 250A/3P 3x95/50+1x50 ”
20. 320A/3P 3x120/70+1x70 ”
21. 400A/3P 3x150/70+1x70 ”
22. 500A/3P 2(3x120/70+1x70) ”
23. 630A/3P 2(3x150/70+1x70) ”
24. 800A/3P 3(3x150/70+1x70) ”
25. 1000A/3P 4(3x150/70+1x70) ”
26. 1250A/3P 4(3x150/70+1x70) ”
27. 1600A/3P 6(3x 150/70+1X70) ”

B. Light fitting and lamps

1 Massive Kirco 37715/06/10 with 3xE27 18W CFL lamps.
2 Massive Kirco 37712/06/10 with 1xE27 18W CFL lamp.
3 RZB 10120.002 A60 with 1xE27 18W CFL lamp.
4 RZB 25185.002 A60 with 1xE27 18W CFL lamp.or eq.
5 Philips TCW 314 with 1xTL-D 36w HFB C# fluroscent lamp or eq.
6 RZB 56125.002 A60 with 1xE27 18W CFL lamp with screw neck glass of 05-56150.Q
7 RZB 56225.002 A60 with 1xE27 18W CFL lamp with screw neck glass of 05-56150.Q
8 30x60 cm LED panel of 36w TechTouch or approved equivalent.