Electrical Installation Design Project_DUBAI STANDARD_ by Mohnad Ibrahim
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Transcript of Electrical Installation Design Project_DUBAI STANDARD_ by Mohnad Ibrahim
Building Electrical Installation Design and Drafting Project Project using UAE (Dubai) Standard 3/28/2015 Electrical Engineer
Mohnad Ibrahim Abdalla Jobbara
Project : Building Electrical Installation Design & Drafting
Flat Design 1
Designed by : Mohnad Ibrahim
Supervisor : Amjed Osman Elsayed
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
Project in Dubai standards (BS)
Dubai Design parameters
Voltage : 230/400
Frequency : 50Hz
Diversity factor “D.F” : 0.9
Power Factor (Cos Ф) : 0.8
Building Specification:
Number of floors : 6 Floors + Ground floor
Number of flats : 36 flats ( 6 flats per floor (3 large “3BHK”, and 3 small “2BHK”) ) All 2BHK flats are typical (same)
All 3BHK flats are typical (same)
Number of lifts : 2 Lifts
Generator to supply power for lift 1 (10 HP), lift 2 (10 HP), Water pump (50 HP), Fire-fighting water
pump (50HP), DB GF.
The building is supplied with central chilled water system (MCC)
a. Chiller -1 100 kW
b. Chiller -2 100 kW
c. AHU -1 50 HP
d. AHU -2 50 HP
e. CHWPP-1(Duty) 20 HP
f. CHWPP-2(DUTY) 20 HP
g. CHWPP-3(Standby) 20 HP
h. CHWSP-1(Duty) 15 HP
i. CHWSP-2(Duty) 15 HP
j. CHWSP-3 (Standby) 15 HP
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
2 BHK Flat Design
Note :
W/H , W/M = 1500 w
FCU 1 Tonne = 1200 w
See Drawings No: 7, 8, 9, 10, 11, 12
- Civil layout drawing
- Furniture layout drawing
- Lighting layout & Shop drawings
- Power layout & Shop drawings
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
Calculation:
Total connected load = (6900+7200+6600) = 20700 W
T.C.L = 20.7 kW
Diversity Factor (D.F) = 0.90 (90% used)
Max Demand = T.C.L x D.F
= 20.7 x 0.9 = 18.63 kW
Calculation of main isolator and main feeder cable of DB-F11
Max demand of DB-F11 = 18.63 kW // 3 Ф
Current (I) = P /( √3 x cos Ф xV
= 18.63 / (1.732 x 0.8x 400)
= 33.61 A
Plus 25% as safety factor
= 33.61 x 1.25 = 42.0125 A
Standard main isolator size = 50 A, 4P
Main feeder cable = 1 x 4C x 10mm², XLPE/SWA/PVC, Cu+ 1 x 1C x 10mm², PVC/PVC, Y/G Earth Cable
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
3 BHK Design
Note :
W/H , W/M = 1500 w
FCU 1 Tonne = 1200 w
See Drawings No: 13, 14, 15 ,16 ,17,18
- Civil layout drawing
- Furniture layout drawing
- Lighting layout & Shop drawings
- Power layout & Shop drawings
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
Calculation:
Total connected load = (9000 + 9100 + 8900) = 27000 W
T.C.L = 27 kW
Diversity Factor (D.F)= 0.90 (90% used)
Max Demand = T.C.L x D.F
= 27x 0.9 = 24.30 kW
Calculation of main isolator and main feeder cable of DB-F14
Max demand of DB-F11 = 24.3 kW // 3 ø
Current (I) = P /( √3 x cos Ф xV
= 24300/ (1.732 x 0.8x 400)
= 43.84 A
Plus 25% as safety factor
= 43.84 x 1.25 = 54.8 A
Standard main isolator size = 60 A, 4P
Main feeder cable = 1 x 4C x 16mm², XLPE/SWA/PVC, Cu+ 1 x 1C x 16mm², PVC/PVC, Y/G Earth
cable
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
DB – GF Design
Total Connected load = 5900 W ,
T.C.L = 5.90kW
Diversity Factor = 0.90 (%90 used)
Max demand = T.C.L X D.F
= 5.9 X 0.90 = 5.31 kW
Calculation of main isolator and main feeder cable of DB-GF
Max demand of DB-GF = 5.31kW // 3ø
Current (I) = P /( √3 x cos Ф xV)
= 5.31 /(1.732 x 0.8x 400)
= 9.58 A
Plus 25 % as safety factor
= 1.25 X 9.58 = 11.975 A
Standard main isolator size = 15 A, 4P
Main feeder cable = 1 x 4C x 4mm², XLPE/SWA/PVC, Cu+ 1 x 1C x 4mm², PVC/PVC, Y/G Earth cable
See Drawings No: 1, 2, 3, 4, 5,6
- Civil layout drawing
- Furniture layout drawing
- Lighting layout & Shop drawings
- Power layout & Shop drawings
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
SMDB – 1F load schedule
S.
NO
Load Design CB Wire Earth T.C.L
(kW)
R (kW) Y (kW) B (kW)
1 DB-F11 (2BHK)
50A, 4p 1 x 4C x 10mm²
1 x 1C x 10mm²
20.7 6.9 7.2 6.6
2 DB-F12
(2BHK)
50A, 4p 1 x 4C x
10mm²
1 x 1C x
10mm²
20.7 6.9 7.2 6.6
3 DB-F13
(2BHK)
50A, 4p 1 x 4C x
10mm²
1 x 1C x
10mm²
20.7 6.9 7.2 6.6
4 DB-F14
(3BHK)
60A, 4p 1 x 4C x
16mm²
1 x 1C x
16mm²
27 9 9.1 8.9
5 DB-F15
(3BHK)
60A, 4p 1 x 4C x
16mm²
1 x 1C x
16mm²
27 9 9.1 8.9
6 DB-F16
(3BHK)
60A, 4p 1 x 4C x
16mm²
1 x 1C x
16mm²
27 9 9.1 8.9
TOTAL LOAD 143.1 47.7 48.9 46.5
Total connected Load = 47.7 + 48.9 + 46.5 = 143.1 kW
Max demand = T.C.L X D.F
= 143.1 X 0.9 = 128.79 kW
Max demand of SMDB-F1 = 128.79 kW // 3ø
Current (I) = P /( √3 x cos Ф xV)
= 128.79/ (1.732 x 0.8 x 400)
= 232.37 A
Plus 25 % as safety factor
= 1.25 x 232.37 = 290.46 A
Standard main isolator size = 300 A, 4P
Main feeder cable = 1 x 4C x 185mm², XLPE/SWA/PVC, Cu+ 1 x 1C x 95mm², PVC/PVC, Y/G Earth cable
NOTE
SMDB-2F to SMDB-6F are Typical to SMDB-1F
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
Central Chilled Water System (MCC)
1. Chiller (1)
P= 100kw 3phase
Current (I) = 100,000/(1.732×400×.8)= 180.42 A
Plus, 25% as safety factor 180.42× 1.25 = 225.525 A
Standard disconnect switch size = 250 A, 4P
Main feeder cable = 1 x4C×150mm²+ 1x1C×95mm² Y/G
2. Chiller (2)
P= 100kw 3phase
Current (I) = 100,000/ (1.732×400×.8)= 180.42 A
Plus, 25% as safety factor 180.42× 1.25 = 225.525 A
Standard disconnect switch size = 250 A, 4P
Main feeder cable = 1 x4C×150mm²+ 1x1C×95mm² Y/G
3. AHU -1 (50HP)
P= 50×746 = 37.3kW
Current (I) = 37300/ (1.732×400×.8) =67.3 A
Plus, 25% as safety factor 67.3 × 1.25 = 84.125 A
Standard disconnect switch size = 100 A, 4P
Main feeder cable = 1 x4C×35mm²+ 1x1C×25mm² Y/G
4. AHU -2 (50HP)
P= 50×746 = 37.3kW
Current (I) = 37300/ (1.732×400×.8) =67.3 A
Plus, 25% as safety factor 67.3 × 1.25 = 84.125 A
Standard disconnect switch size = 100 A, 4P
Main feeder cable = 1 x4C×35mm²+ 1x1C×25mm² Y/G
5. CHWPP-1 (20HP) (Duty)
P= 20×746 =14.92 kW
Current (I) = 14920/ (1.732×400×.8) =26.92 A
Plus, 25% as safety factor 26.92× 1.25 = 33.65 A
Standard disconnect switch size = 40 A, 4P
Main feeder cable = 1 x4C×10mm²+ 1x1C×10mm² Y/G
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
6. CHWPP-2 (20HP) (Duty)
P= 20×746 =14.92 kW
Current (I) = 14920/ (1.732×400×.8) =26.92 A
Plus, 25% as safety factor 26.92× 1.25 = 33.65 A
Standard disconnect switch size = 40 A, 4P
Main feeder cable = 1 x4C×10mm²+ 1x1C×10mm² Y/G
7. CHWPP-3 (20HP) (Standby)
P= 20×746 =14.92 kW
Current (I) = 14920/ (1.732×400×.8) =26.92 A
Plus, 25% as safety factor 26.92× 1.25 = 33.65 A
Standard disconnect switch size = 40 A, 4P
Main feeder cable = 1 x4C×10mm²+ 1x1C×10mm² Y/G
8. CHWSP-1 (15HP) (Duty)
P= 15×746= 11.19 kW
Current (I) = 11190/ (1.732×400×.8)= 20.19 A
Plus, 25% as safety factor 20.19× 1.25 = 25.24 A
Standard Main Isolator size = 30 A, 4P
Main feeder cable = 1 x4C×6mm²+ 1x1C×6mm² Y/G
9. CHWSP-2 (15HP) (Duty)
P= 15×746= 11.19 kW
Current (I) = 11190/(1.732×400×.8)= 20.19 A
Plus, 25% as safety factor 20.19× 1.25 = 25.24 A
Standard Main Isolator size = 30 A, 4P
Main feeder cable = 1 x4C×6mm²+ 1x1C×6mm² Y/G
10. CHWSP-3 (15HP) (Standby)
P= 15×746= 11.19 kW
Current (I) = 11190/ (1.732×400×.8)= 20.19 A
Plus, 25% as safety factor 20.19× 1.25 = 25.24 A
Standard Main Isolator size = 30 A, 4P
Main feeder cable = 1 x4C×6mm²+ 1x1C×6mm² Y/G
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
MCC Load Schedule
S/NO Load
Description
CB Wire earth T.C.L
(kW) R (kW) Y(kW) B(kW) Type of
Motor
Starter
1 Chiller 1 250A,4P 1x4C×150mm² 1x1C×95mm² 100 33.33 33.33 33.33 - 2 Chiller 2 250A,4P 1x4C×150mm² 1x1C×95mm² 100 33.33 33.33 33.33 - 3 AHU 1 100A,4P 1 x4C×35mm² 1x1C×25mm² 37.3 12.43 12.43 12.43 VFD 4 AHU 2 100A,4P 1 x4C×35mm² 1x1C×25mm² 37.3 12.43 12.43 12.43 VFD 5 CHWPP-1
(Duty)
40A, 4P 1 x4C×10mm² 1x1C×10mm² 14.92 4.97 4.97 4.97 Y/▲
6 CHWPP-2 (Duty)
40A, 4P 1 x4C×10mm² 1x1C×10mm² 14.92 4.97 4.97 4.97 Y/▲
7 CHWPP-3
(Standby)
40A, 4P 1 x4C×10mm² 1x1C×10mm² 14.92 4.97 4.97 4.97 Y/▲
8 CHWSP-1 (Duty)
30A, 4P 1 x4C×6mm² 1 x1C×6mm² 11.19 3.73 3.73 3.73 Y/▲
9 CHWSP-2
(Duty)
30A, 4P 1 x4C×6mm² 1 x1C×6mm² 11.19 3.73 3.73 3.73 Y/▲
10 CHWSP-3 (Standby)
30A, 4P 1 x4C×6mm² 1 x1C×6mm² 11.19 3.73 3.73 3.73 Y/▲
TOTAL LOAD 326.76 108.92 108.92 108.92 - * Standby loads are not consider in the calculation of Total load
Total Load Connected = 3 x 108.92 = 326.76 kW
Max demand = T.C.L x D.F
= 326.76 x 1 = 326.76 kW
Max Demand of MCC = 326.76 kW (3 phase)
Current (I) = P /( √3 x cosФ xV)
= (326760)/(1.732 x 400 x 0.8)
= 589.56 A
Plus, 25% as safety factor
= 1.25 x 589.56 = 736.95 A
Standard Main Isolator Size = 800 A, 4P
Main feeder cable for MCC = 2 x4C×300mm². XLPE/SWA/PVC, Cu+ 2x1C×150mm² Y/G
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
SMDB. Comm load calculation
I. Lift 1 (10 HP)
P= 10×746= 7.46 kW
Current (I) = 7460/(1.732×400×.8) = 13.46A
Plus, + 25% as safety factor 13.46× 1.25 = 16.825 A
Standard disconnect switch size = 20 A, 4P
Main feeder cable = 1 x4C×4mm²+ 1x1C×4mm² Y/G
II. Lift 2 (10 HP)
P= 10×746= 7.46 kW
Current (I) = 7460/(1.732×400×.8) = 13.46A
Plus, + 25% as safety factor 13.46× 1.25 = 16.825 A
Standard disconnect switch size = 20 A, 4P
Main feeder cable = 1 x4C×4mm²+ 1x1C×4mm² Y/G
III. Water Pump (50 HP)
P= 50×746= 37.2 kW
Current (I) = 37200 / (1.732×400×.8) = 67.12 A
Plus, + 25% as safety factor 67.12× 1.25 = 83.9 A
Standard disconnect switch size = 100 A, 4P
Main feeder cable = 1 x4C×35mm²+ 1x1C×25mm² Y/G
IV. Fire Fighting Water Pump (50 HP) – F.F.W Pump
P= 50×746= 37.2 kW
Current (I) = 37200 / (1.732×400×.8) = 67.12 A
Plus, + 25% as safety factor 67.12× 1.25 = 83.9 A
Standard disconnect switch size = 100 A, 4P
Main feeder cable = 1 x4C×35mm²+ 1x1C×25mm² Y/G
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
SMDB. Comm load Schedule
S.NO Load
Description
CB Wire Earth Total
Load
R (kW) Y (kW) B (kW)
1 Lift -1 20A,4P 1 x 4C x 4mm² 1 x 1C x 4mm² 7.46 2.486 2.486 2.486
2 Lift -2 20A,4P 1 x 4C x 4mm² 1 x 1C x 4mm² 7.46 2.486 2.486 2.486
3 Water Pump 100A,4P 1 x4C×35mm² 1 x1C×25mm 37.2 12.4 12.4 12.4
4 F.F.W Pump 100A,4P 1 x4C×35mm² 1 x1C×25mm 37.2 12.4 12.4 12.4 5 DB - GF 15A,4P 1 x 4C x 4mm² 1 x 1C x 4mm² 5.9 2 2 1.9
TOTAL LOAD 31.772 31.772 31.672
Total Connected Load = 31.772 + 31.772 + 31.672 = 95.216 kW
Max Demand = T.C.L x D.F
= 95.216 x 0.9 = 85.6944 kW
Max demand of SMDB - Comm = 85.6944 kW (3 ø)
Current (I) = P / (√3 x cosФ xV)
= 85694.4 / (1.732 x 0.8 x 400)
= 154.61 A
Plus, +25% as safety factor
= 154.61 x 1.25
= 193.26 A
Standard main isolator size = 200 A, 4P
Main feeder cable for SMDB - Comm = 1 x4C×95mm². XLPE/SWA/PVC, Cu+ 1x1C×50mm² Y/G
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
MDB Load Schedule
S.No Load
Description
CB Wire Earth Total
Load
R
(kW)
Y
(kW)
B
(kW)
1 SMDB-
Comm
200A,4P 1 x4C×95mm² 1x1C×50mm² 95.216 31.772 31.772 31.672
2 SMDB-1F 300A,4P 1x4C
x185mm²
1 x1C x95mm² 143.1 47.7 48.9 46.5
3 SMDB-2F 300A,4P 1x4C
x185mm² 1 x1C x95mm² 143.1 47.7 48.9 46.5
4 SMDB-3F 300A,4P 1x4C x185mm²
1 x1C x95mm² 143.1 47.7 48.9 46.5
5 SMDB-4F 300A,4P 1x4C
x185mm² 1 x1C x95mm² 143.1 47.7 48.9 46.5
6 SMDB-5F 300A,4P 1x4C
x185mm² 1 x1C x95mm² 143.1 47.7 48.9 46.5
7 SMDB-6F 300A,4P 1x4C
x185mm² 1 x1C x95mm² 143.1 47.7 48.9 46.5
8 MCC 800A,4P 2x4C×300mm² 2x1C×150mm² 326.76 108.92 108.92 108.92
9 Capacitor bank
2000A,3P 4x4C×300mm² 4x1C×150mm²
TOTAL LOAD 426.892 434.092 419.692
*** The load on the phases is not balanced:
- Average power = (426.892 + 434.092 + 419.692) / 3 = 426.892 kW
- By subtracting 7.2 kW from Y phase and add it to B phase, then the phases will be balanced
Total Connected Load (T.C.L) = 426.892 + 434.092 + 419.692 = 1280.676 kW
Max demand = T.C.L x D.F
= 1280.676 x 0.9 = 1152.6084 kW
Max demand of MDB = 1152.6084 kW (3 ø)
Current (I) = P / (√3 x cosФ xV)
= 1152608.4 / (1.732 x 0.8 x 400)
= 2079.62 A
Plus, + 25% as Safety factor
= 2079.62 x 1.25 = 2599.525 A
Standard Main Isolator size = 3000 A, 4P, ACB
Main feeder Cable for MDB (Main Distribution Board) :
5x4C×300mm²XLPE/SWA/PVC+ 5x1C×150mm² Y/G
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
Transformer Sizing
1. Max demand of MDB = 1152.608 kW
2. Total max demand of MDB in kVA = Power (kW) / CosФ
= 1152.608 kW / 0.8
= 1440.76 kVA
3. Add 10 % as future load
Max demand in kVA = 1440.76 x 1.10 = 1584.836 kVA
4. Transformer Size = (Total max demand with future load in kVA/ Transformer load (90%))
= 1584.836 kVA / 0.90
= 1760.92kVA
Standard Transformer size = 2000kVA,
Voltage : 11kV/ (400-230V), Step-down, 3phase.
Frequency : 50 Hz,
Winding : Delta/Star,
Cooling : Air Cooled
Capacitor Bank Sizing
Size = Max demand MDB in kW x {tan (cos-¹ø1) - tan (cos-¹ø2)}
= 1152.608 kW x {tan (cos-¹0.8) - tan (cos-¹0.98)}
= 1152.608 kW x {tan (36.87) - tan (11.478)}
= 1152.608 kW x {0.75 -0.203}
= 630.47 kVAR
Standard size of Capacitor bank = 750 kVAR
Current (I) = P / (√3×sinø×V) = 630.47 kVAR / (1.732 x 0.6 x 400)
= 1516.71 A
Plus, +25% as safety factor = 1516.71 x 1.25
= 1895.88 A
Standard main Isolator size = 2000 A, 3P
Main feeder cable for MDB = 4x4C×300mm²+ 4x1C×150mm² Y/G
Generator Sizing
Max demand SMDB-Comm = 85.6944 kW
Max demand in kVA = Power (kW) / CosФ
= 85.6944 kW / 0.8 = 107.118 kVA
Generator Size = ( Total max demand in kVA / Generator load (80%) )
= (107.118 kVA / 0.8) = 133.8975 kVA
Standard Generator Size = 160 kVA, 3phase, 4 wire 230/400, 50 Hz
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
Cable tray layout and Panel Board location
Cable tray sizing
(1)→(1)
No of cables: 8 (MDB to SMDB-F (1-6) – MDB to MCC)
Cable size (MDB to SMDB-F (1-6)) = 1x4C×185mm² + 1x1C×95mm² Overall dia mm 56.4
Cable size (MDB to MCC) = 2x4C×300mm² + 2x1C×150mm² Overall dia mm 67.9
28.2+ 11×56.4 + 4×67.9+2 x 33.95 = 988.1
Standard cable tray size = 2 x (500mm×100mm), because the size exceeded standard cable tray size
(2)→(2) :
No of cables : 2 ( MDB to ATS – ATS to SMDB.Comm)
Cable size MDB to ATS = 1x4C×95mm² + 1x1C×50mm²
Cable size ATS to SMDB.Comm = 1x4C×95mm² + 1x1C×50mm²
Overall dia mm 42.0
(42× 3) + (21×2) = 168
Standard cable tray size = 200mm×200mm
(3)→(3) :
No of cables : 2 (SMDB.Comm to lift 1 and lift 2 )
Cable size lift 1 = 1x4C×4mm² + 1x1C×4mm²
Cable size lift 2 = 1x4C×4mm² + 1x1C×4mm²
Overall dia mm 16.9
Then (16.9× 3) + (8.45×2) = 67.6
Standard cable tray size = 100mm×100mm
(4)→(4)
No of cables : 2 (SMDB - Comm to Water pump and F.F Pump )
Cable size of water pump = 1x4C×35mm² + 1x1C×25mm²
Cable size of F.F.pump = 1x4C×35mm² + 1x1C×25mm²
Overall dia mm 32.2
Then, ( 32.2× 3) + (16.1×2)= 128.8
Standard cable tray size = 150mm×150mm
(5)→(5) :
No of cables : 3 (SMDB - Comm to water pump, F.F.pump ,and DB-GF )
Cable size of water pump = 1x4C×35mm² + 1x1C×25mm² Overall dia mm 32.2
Cable size of F.F.pump = 1x4C×35mm² + 1x1C×25mm Overall dia mm 32.2
Cable size of DB-GF = 1×4C×6mm² + 1x1C×6mm² Overall dia mm 19
Then, (16.1 x 2) + (32.2×3) + (19) + (9.5)= 157.3
Standard cable tray size = 200mm×200mm
(6)→ (6):
No of cables 1(DB-GF )
Cable size of DB-GF = 1×4C×4mm² + 1x1C×4mm²
Overall dia 4core DB-GF 16 = 16.9
Then, (2×8.45) + (16.9)= 33.8
Standard cable tray size = 50mm x 50mm
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
Cable Schedule
From To Size Length
MDB MCC 2x4C×300mm² 35 meters
MDB SMDB-Comm 1x4C×95mm² 10 meters
MDB SMDB-1F 1x4C x185mm² 15 meters
MDB SMDB-2F 1x4C x185mm² 20 meters
MDB SMDB-3F 1x4C x185mm² 30 meters
MDB SMDB-4F 1x4C x185mm² 40 meters
MDB SMDB-5F 1x4C x185mm² 50 meters
MDB SMDB-6F 1x4C x185mm² 60 meters
Voltage drop calculation
Note
The total voltage drop from MDB to DB or final mechanical equipment, must be less than 4% if
not, then we have to increase the cable size
Calculation of the voltage drop from MDB to DB-F64
% Vd (MDB - DB-F64) = %Vd (MDB - SMDB-6F) + % Vd (SMDB – DB-F64)
1. % Vd (MDB to SMDB-6F)
Vd = I ×L (Meter) × VD / (R× 1000)
Cable size = 1x4C x185mm²
I = current of max demand of SMDB-6F = 232.37 A
L = 60 Meters, R = 1
VD = 0.26 (See page 34, cable data table)
Vd = (232.37 × 60× 0.26)/(1000×1) = 3.63 V
%Vd = (3.63/400) ×100 = % 0. 9075
2. %Vd (SMDB-6F to DB-F64)
Vd = I ×L (Meter) × VD / (R× 1000)
Cable size = 1 x 4C x 16mm²
I = current of max demand of DB-F64 = 43.84 A
L = 20 Meters
VD = 2.5 (See page 34, cable data table)
R = 1
Vd = (43.84 × 20× 2.5)/(1000×1) = 2.192 V
%Vd = (2.192/400) ×100 = % 0.548
Voltage drop:
% vd (MDB - DB-F64) = %Vd(MDB - SMDB-6F) + % Vd (SMDB-6F – DB-F64)|
= 0.9075% + 0.548 %
= 1.46 %, (voltage drop Less than 4%, so it is acceptable sizes)
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
Calculation of the voltage drop from MDB to Chiller
% Vd (MDB- chiller1)= %Vd(MDB-MCC) + % Vd(MCC-Chiller1)
1. %Vd(MDB-MCC) :
Vd = I ×L (Meter) × VD / (R× 1000)
Cable size = 2x4C×300mm²
I = current of max demand of MCC = 589.56 A
L = 35 Meters
VD = 0.185 (See page 34, cable data table)
R = 2
Vd = (589.56 × 35× 0.185)/(1000×2) = 1.9087 V
%Vd = (1.9087/400) ×100 = % 0.48
2. % Vd(MCC-Chiller1):
Vd = I ×L (Meter) × VD / (R× 1000)
Cable size = 1x4C×150mm²
I = current of max demand of MCC = 180.42 A
L = 30 Meters
VD = 0.30 (See page 34, cable data table)
R = 1
Vd = (180.42 × 30× 0.30) / (1000×1) = 1.62378 V
%Vd = (1.62378/400) ×100 = % 0.406
Thus, % Vd (MDB- chiller1) = %Vd(MDB-MCC) + % Vd(MCC-Chiller1)
= 0.48 % + 0.406%
= 0.886 % (< 4 % “less than 4%)
So, the sizes of all cables are in acceptable range, the cables are OK
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
Short circuit calculation
Method to be used for calculation: Per- unit method
Z → Impedance
P.u→ per unit
Assume base MVA = 100MVA
Collect information from nearest substation about the fault level.
Fault level = 350 MVA
Steps:
(1) Zpu network = Base MVA/ Fault MVA
(2) Zpu T/F = (Z% × Base MVA)/(100×T/F MVA)
T/F = 2000 kVA = 2 MVA * T/F = Transformer
(3) Zpu cable:
Z cable = (Z/Km× L(Meters))/(R×1000)
Z/Km = page no .106
Zpu cable = (base MVA×Zcable)/ (KV)²
V=400 = 0.400 kV
(4) Total Zpu MDB = Zpu net + Zpu T/F + Zpu cable
(5) Fault MVA at MDB = Base MVA/Totale Zpu
(6) Short –circuit rating of MDB = Fault MVA/ (√3×kV) = kA
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
Calculation of the short circuit current for MDB, SMDB-1F, DB-F11
(1) Zpu network = Base MVA/ Fault MVA
= (100 MVA)/(350MVA)= 0.286Pu
(2) Zpu T/F = (Z% × Base MVA)/(100×T/F MVA)
T/F = 2000KVA = 2MVA
= (5×100MVA)/(100×2MVA)= 2.5Pu
(3) Zpu cable: (T/F to MDB) 4×4C×300mm²
Z cable = (Z/Km× L(Meters))/(R×1000)
Z/Km = 0.1212 , L (Meters) = 15 meters
= (0.1212 × 15)/(5×1000) = 0.0003636 Ω
Zpu cable(T/F to MDB) = (base MVA×Z cable)/ (KV)²
V=400 = 0.400 KV
= (100MVA×0.0003636)/(0.400)²
= 0.22725 Pu
(4) Total Zpu MDB = Zpu net + Zpu T/F + Zpu cable
= 0.286 + 2.5 + 0.22725 = 3.01325 pu
(5) Fault MVA at MDB = Base MVA/Total Zpu
= (100MVA)/(3.01325) = 33.187 MVA
Short –circuit rating of MDB = Fault MVA/ (√3×kV)
= (33.187 MVA)/(1.732×0.400 kV) = 47.9027 kA
Standard short-circuit rating at MDB = 50 KA
(1) Zpu cable : (MDB to SMDB-1F) : 1×4C×185mm²
Z cable = (Z/Km× L(Meters))/(R×1000)
Z/Km = 0.184 , L meters = 35meters
= (0.184 × 35) / (1×1000) = 0.00644Ω
Zpu cable (MDB to SMDB-1F) = (base MVA×Z cable)/ (kV) ²
V= 400 V = 0.400 kV
= (100MVA×0.00644)/(0.400)²
= 4.025 Pu
(2) Total SMDB-1F = Zpu MDB + Zpu cable (MDB TO SMDB-1F)
= 3.01325 + 4.025 = 7.03825 pu
(3) Fault MVA at SMDB-1F = Base MVA/Total Zpu
= (100MVA)/ (7.03825) = 14.208 MVA
Short –circuit rating of SMDB-1F = Fault MVA/ (√3×kV)
= (14.208 MVA)/(1.732×0.400 kV) = 20.51 kA
Standard short-circuit rating at SMDB-1F = 25 KA
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
(3) Zpu cable : (SMDB-1F to DB-F11) : 1×4C×10mm²
Z cable = (Z/Km× L(Meters))/(R×1000)
Z/Km = 2.336 From page no (106) in the manual
= (2.336 × 20)/(1×1000) = 0.04672Ω
Zpu cable (SMDB-1F to DB-F11) = (base MVA×Z cable)/ (kV)²
V= 0.400 = 0.400 kV
= (100MVA×0.04672)/(0.400)²
= 29.2 pu
Total Zpu(SMDB-1F toDB-F11
= Zpu SMDB-1F + Zpu cable (SMDB1Fto DB-F11)
= 7.03825 + 29.2 = 36.23825 pu
Fault MVA at DB-F11 = Base MVA/Total Zpu
= (100MVA) / (36.23825) = 2.76 MVA
Short –circuit rating of DB-F11 = Fault MVA/ (√3×kV)
= (2.76 MVA) / (1.732 × 0.400 kV) = 3.98 KA
Standard short-circuit rating at DB-F11 = 6 KA
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
Drawings:
Civil Layout Drawing No (1)
Lighting Layout Drawing No (2)
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
Lighting Shop Drawing No (3)
Power Layout drawing No (4)
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
Power Shop Drawing No (5)
Ground Floor Cable Tray Layout Drawing No (6)
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
Civil Layout Drawing No (7)
Furniture Layout Drawing No (8)
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
Lighting Layout Drawing No (9)
Lighting Shop drawing No (10)
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
Power Layout Drawing No (11)
Power Shop Drawing No (12)
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
Civil Layout Drawing No (13)
Furniture Layout Drawing No (14)
Lighting Layout Drawing No (15)
Building Electrical Installation Design Project
Designed by: Mohnad Ibrahim Abdalla Jobbara
Lighting Shop Drawing No (16)
Power Layout Drawing No (17)
Power Shop Drawing No (18)