electrical design philosophy for major types of buildings

7/22/2019 Electrical Design Philosophy for Major Types of Buildings

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Electrical Design Philosophy for Major Types of Buildings:

Introduction:

fig (1)

Look around in your region, you will discover that a lot of different size buildingssurround you and of course each one of them is constructed for a certain purpose (seefig.1), these different purposes give us a guide for classification of these buildings i.e. allthese Buildings will be classified according to their usage but before we list differenttypes of buildings, we need to focus on the following Important facts about buildings:


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Buildings are usually created for a specific function; Abuilding's function strongly influences its design and construction.

A building is a product, a product is not more than a

packaging of functions, and you must have best design & goodselection of product materials to realize its best functions and toget a product (building) satisfy your anticipations.

Design is information processing, Output is not a building, butinformation to enable others to utilize that building.

Why an electrical designer must be familiar with the Major Types of buildings?That is because that the electrical network configuration is determined dependent on therequirements resulting from the buildings use and other additional factors which makesevery building to be unique in its own way.

As professionals want to make efficient Electrical Design, it is important to have apreliminary imagination for every building type and that we will do in the followingtopics.

Major Types of buildings: see fig.2

1. Industrial buildings

2. Commercial buildings

3.

Residential buildings4. Agricultural buildings

5. Educational buildings

6. Transportation buildings

7. Religious buildings

8. Parking and storage

9. Military buildings

10. Governmental buildings

11. Cultural buildings

12. Other buildings


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fig (2): Major Types of buildings

1- Industrial buildings:

A building designed to house industrial operations and provides the necessary conditionsfor workers and the operation of industrial equipment.

2- Commercial buildings:A building with more than 50 percent of its floor space used for commercial activities.Commercial buildings include, but are not limited to, office buildings, industrial property,medical centers, hotels, malls, retail stores, shopping centers, farm land, multifamilyhousing buildings, warehouses, and garages.

3- Residential buildings:A building used or designed to be used in whole or in part for residential purposes andincludes an associated outbuilding of and other improvement to a building used or

designed to be used in whole or in part for residential purposes, but does not include afloating mobile home.

4- Agricultural buildings :Agricultural buildings are structures designed for farming and agricultural practices,including but not limited to: growing and harvesting of crops and raising livestock andsmall animals.

5- Educational buildings :Buildings used for academic or technical classroom instruction, such as elementary,middle, or high schools, and classroom buildings on college or university campuses.

Buildings on education campuses for which the main use is not classroom are included inthe category relating to their use. For example, administration buildings are part ofOffice, dormitories are Lodging, and libraries are Public Assembly.

6- Transportation buildings :A building Include machines that used as means of transportation, they include, but arenot limited to, railway station, airports, and sea ports.


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7- Religious buildings:Buildings in which people gather for religious activities, (such as chapels, churches,mosques, synagogues, and temples)

8- Parking and storage:A building /Space in which to park vehicles.

9- Military buildings :They are any structure designed to house functions performed by a military unit.

10-Governmental buildings :A building that houses a branch of government.

11-Cultural buildings:A building contain any type of Cultural Heritage they include, but are not limited to,museums, libraries, theaters, cinemas.

12-Other buildings:A building that is not included in all building types above like mobile homes.

Buildings Basic electrical design philosophy :see fig.3


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fig (3):Examples for different types of building useand their impact on electric design Philosophy

The following basic considerations are fundamental to any power system design:

1- Basic Safety:The power system must be able to perform all of its basic functions, and withstand basicabnormal conditions, without damage to the system or to personnel.

2- Basic Functionality:The power system must be able to distribute power from the source to the connected


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loads in a reliable manner under normal conditions.

3- Reasonable Cost:The power system cost to obtain basic safety and functionality should be reasonable.

4- Code Compliance:All applicable codes must be complied with.

Above and beyond the basics are a multitude of considerations, some of which will applyto each particular system design:

1- Enhanced Safety:The ability to withstand extremely abnormal conditions with a minimum of risk topersonnel

2- Enhanced Reliability:

The ability to maintain service continuity during abnormal system conditions

3- Enhanced Maintainability:The system can be maintained with minimum interruption to service and with minimumpersonnel protective equipment.

4- Enhanced Flexibility:The ability to add future loads to the system, and with loads of a different nature thancurrently exist on the system

5- Enhanced Space Economy:

The power system takes up the smallest possible physical space.

6- Enhanced Simplicity:The power system is easy to understand and operate.

7- Reduced Cost:The power system costs, both first cost and operating cost, are low.

8- Enhanced Power Quality:The power system currents and voltages are sinusoidal, without large amounts ofharmonics present. System voltage magnitudes do not change appreciably.

9- Enhanced Transparency:The power system data at all levels is easily acquired and interpreted, and the powersystem is easily interfaced with other building systems. Enhanced control of the system isalso possible.


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In the previous topic,Electrical Design Philosophy for Major Types of Buildings,We talkabout the different types of buildings and how the building type (function) influence itselectrical design.

This was very clear in our previous discussions for the electrical design requirements ofthe industrial buildings which were included in the following topics:

Electrical Design Requirements for Industrial Building

Specific Electrical Design Requirements for IndustrialBuildings Part One

Specific Electrical Design Requirements for IndustrialBuildings Part Two

Today, I will explain the second type of buildings which is Commercial buildings andclarify the electrical requirements of this type of buildings.

Commercial building definition:

A building with more than 50 percent of its floor space used for commercial activities.

Commercial buildings include, but are not limited to, office buildings, industrial property,medical centers, hotels, malls, retail stores, shopping centers, farm land, multifamilyhousing buildings, warehouses, and garages.

Commercial building Classifications:

The commercial buildings category include many types of buildings vary from traditionalbuildings like offices, Retail, Multi Family, self storage, etc. and Non-Traditional buildingslike Auto Repair Shops, Hotels & Motels, Pharmacies, Daycare Centers, OutdoorEntertainment Centers, etc.

However, the commercial buildings can be classified to main five categories included in

the following table:

# Category Examples

1 Leisure hotels, public houses, restaurants, cafes, sports facilities
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2 Retail retail stores, malls, shopping centers, shops

3 Office office buildings, serviced offices

4 Residential multifamily housing buildings

5 Healthcare medical centers, hospitals, nursing homes

Commercial building types examples per category:

First: Leisure category

1- Hotel

Hotel applies to buildings that rent overnight accommodations on a room/suite basistypically including a bath/shower and other facilities in guest rooms.

Hotel properties typically have daily services available to guests including housekeeping/laundry and a front desk/concierge. The total gross floor area should include thefollowing spaces:

all interior space, including guestrooms, halls, lobbies, atria,food preparation and restaurant space, conference and banquetspace, health clubs/spas, indoor pool areas, and laundry facilities.

as well as all space used for supporting functions such aselevator shafts, stairways, mechanical rooms, storage areas,employee break rooms, back-of-house offices, etc.

Hotel does not apply to properties where more than 50% of the floor area is occupied byfractional ownership units such as condominiums or vacation timeshares. Hotel propertiesshould be majority-owned by a single entity and have rooms available on a nightly basis

2- Restaurant


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Restaurant is a commercial building where meals are prepared and served to customers,it typically include the following spaces:

Entry and Waiting Area.

Dining Room.

Bar or Lounge.

Walk-up Service or Take Out Counter.

Restrooms (ADA compliant).

Kitchen.

Hostess and Wait Stations.

Ample Aisle and Circulation Space.

Dry and Refrigerated Storage.

Office and Employee Amenities.

3- Sports Facilities

Are building where people can go to play many different types of sports.

Sports facilities typically include the following spaces:

ADMIN BUILDING/INDOOR

GYMNASIUM

INDOOR SPORTSFACILITY

OUTDOORFACILITIES

OTHERFACILITIES

Lobby Table TennisS-Lane, Track &Field Court/Soccer

Parking Spaces

waiting area Dartslong and Triplejump

Bleachers

Admin Office Squash High jump Security Off

Manager's Office Billiards Pole VaultCanteen/s/ FoodCourt

Accounting Badminton Hummer throw Sleeping areas

Bookingweight Training/Fitness Gym

Discuss throw Dining Areas

Personnel Javelin Throw Souvenir Shops

ConferenceRoom/s

Putting & ShotTrophy Case/Bulletin board

Ticket Area Basketball


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Courts/s

Clinic/EmergencyFacility

Volleyball Court/s

Toilets Baseball field

Storage Space Lawn Tennis

50 meter/ 8lane/s swimmingpool

Diving (SpringBoard Platform

Second: Retail Category

1- Retail Store

Retail Store applies to facility space used to conduct the retail sale of consumer productgoods.

Stores must be at least 5,000 square feet and have an exterior entrance to the public.The total gross floor area should include All supporting functions such as kitchens andbreak rooms used by staff, storage areas, administrative areas, elevators, stairwells, etc.

Retail segments typically included under this definition are: Department Stores, DiscountStores, Supercenters, Warehouse Clubs, Drug Stores, Dollar Stores, Home

Center/Hardware Stores, and Apparel/Hard Line Specialty Stores (e.g. books, clothing,office products, toys, home goods, and electronics).

Retail segments excluded under this definition are: Supermarkets (eligible to bebenchmarked as Supermarket space), Convenience Stores, Automobile Dealerships, andRestaurants.

2- Supermarket


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The Supermarket/Grocery Store space type applies to facility space used for the retailsale of food and beverage products. The total gross floor area should include allsupporting functions such as kitchens and break rooms used by staff, storage areas(refrigerated and non-refrigerated), administrative areas, stairwells, atria, lobbies, etc.

Third: Office Category

1- Office buildings

Office applies to facility spaces used for general office, professional, and administrativepurposes. The total gross floor area should include all supporting functions such askitchens used by staff, lobbies, atria, conference rooms and auditoria, fitness areas forstaff, storage areas, stairways, elevator shafts, etc. The following information is requiredfor an Office Space

Forth: Residential Category

1- Multifamily Housing

The Multifamily space type as a residential building equal to or larger than 3 units whichis either rented, leased, let or hired out, to be occupied, or is occupied, as the residenceor home of three or more families living independently of each other. Multifamily spacetypes include all square footage in the residential units, common areas, andunconditioned space (boiler room). Occupants of Multifamily housing can include tenants,
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cooperators, and/or individual owners

2- Single Family Housing

A single-family house is contained within walls extending from the basement (or theground floor, if there is no basement) to the roof.

Fifth: Healthcare Category

1- Hospital (General Medical and Surgical)

Hospitals are Buildings used as diagnostic and treatment facilities for inpatient care. itapplies to a general medical and surgical hospital that is either a stand-alone building ora campus of buildings.

These facilities provide acute care services including emergency medical care, physician'soffice services, diagnostic care, ambulatory care, surgical care, and limited specialtyservices such as rehabilitation and cancer care.

The definition of Hospital accounts for all space types that are located within theHospital building/campus, such as medical offices, administrative offices, and skillednursing. The total floor area should include the aggregate floor area of all buildings onthe campus as well as all supporting functions such as: stairways, connecting corridorsbetween buildings, medical offices, exam rooms, laboratories, lobbies, atria, cafeterias,storage areas, elevator shafts, and any space affiliated with emergency medical care, ordiagnostic care.

2- Medical Office

Medical Office applies to facility space used to provide diagnosis and treatment formedical, dental, or psychiatric outpatient care. The total gross floor area should includeall supporting functions such as kitchens used by staff, laboratories, lobbies, atria,
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conference rooms and auditoria, fitness areas for staff, storage areas, stairways, elevatorshafts, etc.

General Electrical System requirements for Commercial buildings:

The fundamental objective of commercial building design is to provide a safe,comfortable, energy-efficient, and attractive environment for living, working, andenjoyment. The electrical design must satisfy these criteria if it is to be successful.

Todays commercial buildings, because of their increasing size and complexity, havebecome more and more dependent upon adequate and reliable electric systems.

One can better understand the complex nature of modern commercial buildings byexamining the Electrical System requirements systems.

The systems, equipment, and facilities that must be provided to satisfy functionalrequirements will vary with the type of facility, but will generally include some or all ofthe following:

1. Building electric service.

2. Power distribution system.

3. Lighting Interior and exterior, both utilitarian anddecorative; task and general lighting.

4. Communications Telephone, facsimile, telegraph,satellite link, building-to-building communications (includingmicrowave, computer link, radio, closed-circuit television,

code call, public address, paging, fiber optic and electronicintercommunication, pneumatic tube, doctors and nursescall, teleconferencing), and a variety of other signalsystems.

5. Fire alarm systems Fire pumps and sprinklers, smokeand Fire detection, alarm systems, and emergency publicaddress systems.

6. Transportation: Elevators, moving stairways,dumbwaiters, and moving walkways.

7. Space conditioning: Heating, ventilation, and airconditioning.

8. Sanitation: Garbage and rubbish storage, recycling,compaction, and removal; incinerators; sewage handling;and document shredders and pulpers.

9. Plumbing: Hot and cold water systems and watertreatment facilities.

10. Security watchmen, burglar alarms, electronic accesssystems, and closed-circuit surveillance television.


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11. Business machines: Typewriters, computers,calculators, reproduction machines, and word processors.

12. Refrigeration equipment.

13. Food handling, catering, dining facilities, and foodpreparation facilities.

14. Maintenance facilities.15. Lightning protection.

16. Automated building control systems.

17. Entertainment facilities and specialized audiovisualsystems.

18. Medical facilities.

19. Recreational facilities.

20. Legally required and optional standby/emergencypower and peak-shaving systems.

21. Signing, signaling, and traffic control systems; parking

control systems including automated parking systems.

Commercial buildings voltage classifications:

commercial buildings are primarily people- and public-oriented and because of theirdifferent sizes and types, they can need electrical supply with different voltage classes ,for examples simple residential building will need an electrical supply with low voltageclass (under 1000 V) from public Low Voltage grid while a commercial building used ashealth care facilities will need an electrical supply with medium voltage class (UP to

20KV) Via public or in-house MV substations, for more information about different voltageclasses , please review the following links:

Course EE-1 : Voltage Ranges -Part One

EE-1 Course: Voltage Ranges - Part Two

For more information aboutElectrical System Configurationspress on the link.

In the next topic, I will explain the specific electrical design requirements forcommercial buildings. So, please keep following.
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Introduction:In the previous Topic General Electrical Design Requirements for CommercialBuilding", I explain the types of Commercial building and the general outlines of electricalrequirements for these buildings.

Commercial buildings

Today, I will explain in detail the specific Electrical Requirements for CommercialBuildings which must be known for any engineer wants to learn or practice the electricaldesign engineering.The following aspects should be taken into consideration when designing electric power

distribution systems for Commercial buildings:

Simplification of operational management by transparent, simple power systemstructures.

Low costs for power losses, e.g. by medium-voltage-side power transmission to theload centers.

High reliability of supply and operational safety of the installations even in theevent of individual equipment failures (redundant supply, selectivity of the power systemprotection, and high availability).

Easy adaptation to changing load and operational conditions.

Low operating costs thanks to maintenance-friendly equipment.

Sufficient transmission capacity of equipment during normal operation and also inthe event of a fault, taking future expansions into account.

Good quality of the power supply, i.e. few voltage changes due to loadfluctuations with sufficient voltage symmetry and few harmonic distortions in the voltage.

Compliance with applicable standards and project related stipulations for specialinstallations.
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It is known for all designers that the general factors affecting the network configurationselection and design in commercial buildings are as follows:

1. The respective supply task.

2.

The building dimensions.3. The number of stories above / below ground.

4. The building use.

5. The building equipment and power density.

any designer wants to optimize his design by completely satisfying the individual needs ofthe building users, and in case of Commercial building design , these individual needs willbe generally as follows:

1. Low investment.

2. Straightforward network configuration.

3. High reliability and quality of supply.

4. Low power losses.

5. Favorable and flexible expansion options.

6. Low electromagnetic interference.

And any network configuration must be characterized by the following:

Number of feeder points.

Type of meshing and size of the power outage reserve.

Size and type of power sources.

Types of LV networks configurations:

The stated characteristics in above divide network configurations into two main types asfollows:

1. Radial networks.

2. Ring / Mesh networks.

1- Radial networks:


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Radial Network

Low-voltage-side power distribution within buildings is preferably designed in a radialtopology and generally the radial networks have the following advantages:

Easy monitoring of the power system.

Fast fault localization.

Easy and clear power system protection.

Easy operation.

2- Ring / Mesh networks


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Ring / Mesh Network

Operating a meshed low-voltage system with distributed transformer feed-in locationsplaces high requirements on the design and operation of the power system. For thisreason, ring-type systems in combination with high-current busbar trunking systems arepreferred today, in particular in highly consumptive industrial processes. The advantageof a ring-type system with distributed transformer feed-in locations in the load centers ascompared to central feed-in with a radial network will be as follows:

The reliable and flexible supply of power consumers,

The better voltage maintenance, in particular in case of load changes,

Lower power losses.

In theBasic Electrical design course EE-2 Level I, I will explain in detail the using ofradial and ring networks concepts in the following stages (see fig.1):

Configurations of LV side power distribution within buildings

Connection to the upstream Networks (MV side power distribution)

Configurations of MV side power distribution
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Fig.1

In this course ,EE-1: Beginners' Electrical design course, We will study the famouspower system architectures for the commercial buildings which can be counted as

references can be modified/ extended to meet specific customer project requirements.

These famous power system architectures for the commercial buildings include:

Low building, type 1: One supply section.

Low building, type 2: Two supply sections.

High-rise building, type 1: Central power supply, cables.
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High-rise building, type 2: Central power supply, busbars.

High-rise building, type 3: Transformers at remote location.

High-rise building, type 4: Distributed supply, cables.

High-rise building, type 5: Distributed power supply, busbars.

In the previous Topic;Specific Electrical Design Requirements for CommercialBuildings, I listed the famous power system architectures for the commercial buildings asfollows:

1. Low building, type 1: One supply section.

2. Low building, type 2: Two supply sections.

3. High-rise building, type 1: Central power supply,cables.

4. High-rise building, type 2: Central power supply,busbars.

5. High-rise building, type 3: Transformers at remote

location.

6. High-rise building, type 4: Distributed supply, cables.

7. High-rise building, type 5: Distributed power supply,busbars.

And today, I will explain these types in detailed.

Low building, type 1: One supply section

Conditions for using this power system architecture:1- If the following rule is verified:

The number of building floors must not exceed the max. Number of floors for one supplysection (i) calculated by equation#1.

If:Max. Side length of the building = a (in meter)

One Floor area A = a2 (in square meter)

Height per floor = h (in meter)

Then:

Max. Number of floors for one supply section (i) (100 2a) / h (equation#1)

If the number of floors exceed the max. Number of floors for one supply section (i)calculated by equation#1, then we must use other types of power system architecture.
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Note:all buildings have number of floors 4 are low rise buildings.

2-If the (Ground area / total area) of the building 2,500 m2 / 10,000 m2

Note:if floor area 2,500 m2, so there will be only one central equipment room per floorfeed from the LVMD (Low Voltage Main Distribution switchgear)

3- If the power density of the building loads have the following limits: Power required 1,000 to 2,000 kW

Segmentation of power required 85 % utilized area (i.e.functional area like Offices, Briefing rooms, Data center, Canteenkitchen with casino, Heating/ventilation/air conditioning, Fireprotection and Transport) And 15 % side area (i.e. shafts,fountains, green area, sky lighting area and etc.)

4- If the power supply needed for the building have the following requirements:

Supply types 100 % total power from the public grid; (Supplyof all installations and consumer Devices available in the building).

1030 % of the total power for safety power supply (SPS) fromgenerators; (Supply of life-protecting facilities in case of danger,e.g.: Safety lighting, Elevators for firefighters, Fire-extinguishingequipment).

520 % of the total power for uninterruptible power supply(UPS); (Supply of sensitive consumer devices which must beoperated without interruption in the event of a NPS failure / fault,e.g.: Tunnel lighting, airfield lighting, and Servers / computers andCommunications equipment).

Example for one supply section power system architecture:

We have a building with 1200 VA total load power, 4 floors and floor area 2,500 m2 withtotal area 10,000 m2.

Solution selected for this building is using the one supply section power system

architecture as follows:

Design solutionAdvantages of this

solutionBenefits from this

solution

Using Central transformersupply close to load center

Supply at the load center,short LV cables, low losses

Low costs, time savingsduring installation


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Radial network Transparent structureEasy operation andfault localization

Transformer module with 2 630 kVA,

Voltage stability, lighterdesign

Optimized voltagequality, economical

Redundant supply unit: Generator 400 kVA (30 %)(the smaller the generator,the greater the short-circuit current must be inrelation to the nominalcurrent)

UPS 200 kVA (15 %)

Supply of importantconsumers on all floors inthe event of a fault,e.g. during power failureof the public grid

Increased reliability ofsupply

Safety power supplySafety power supply inacc. with DIN VDE0100-718

Supply of sensitive andimportant consumers

Uninterruptible supply

ofconsumers, e.g. duringpower failure of thepublic grid

Use Medium-voltageswitchgear from type SF6gas-insulated

Compact switchgear;independent of climate

Minimized spacerequirementsfor electric utilitiesroom; no maintenancerequired

Use Transformer from typecast-resin with reducedlosses

Low fire load, indoorinstallation

Economical

Use Low-voltage maindistribution with centralgrounding point( whichsplitting of PEN in PE and Nto the TN-S system)

EMC-friendly power system

Protection fromelectromagneticinterference (e.g. topreventlower transmissionrates atcommunication lines)

Use Wiring / main route ascables

Central measurement ofcurrent,voltage, power,e.g. for billing, cost centerallocation

Cost transparency

Use Connection inside Easy installation


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substation ( Transformer LVMD- NPS SPS) as busbars

And the power system architecture will be as follows:

one supply section power system architecture

Where:


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NPS Normal power supply

PCO Power company or system operator

FF Firefighters

HVAC Heating Ventilation Airconditioning

MS Medium-voltage switchboardLVMD Low-voltage main distribution

SPS Safety power supply

UPS Uninterruptible power supply

z Power monitoring system


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In the previous Topic;Power system architectures for the commercial buildings PartOne, I explained the first type of Power system architectures for the commercialbuildings which was Low building, type 1: One supply section and today I will explainthe second type; Low building, type 2: Two supply sections as follows.

You can also review previous topics about electrical design requirements for commercialbuildings for good following-up:

General Electrical Design Requirements for CommercialBuildings

Specific Electrical Design Requirements for CommercialBuildings

2- Low building, type 2: Two supply sections

Conditions for using this power system architecture:

1- If the following rule is verified:

The number of building floors must not exceed the max. Number of floors for Two supplysections (i) calculated byequation#1.

If:

Max. Side length of the building = a (in meter)

One Floor area A = a2 (in square meter)

Height per floor = h (in meter)

Then:

Max. Number of floors for Two supply sections (i) (100 2a) / h (equation#1)

If the number of floors exceed the max. Number of floors for one supply section (i)calculated by equation#1, then we must use other types of power system architecture.

Note:all buildings have number of floors 4 are low rise buildings.

2- If the floor area of the building > 2,000 m2.

Note:if floor area > 2,000 m2, so there will be more than one ( 2) central equipmentroom per floor feed from the LVMD (Low Voltage Main Distribution switchgear).
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3- If the power density of the building loads have the following limits:

Power required >2,000 kW.

Segmentation of power required 85 % utilized area (i.e.functional area like Offices, Briefing rooms, Data center, Canteenkitchen with casino, Heating/ventilation/air conditioning, Fireprotection and Transport) And 15 % side area (i.e. shafts,fountains, green area, sky lighting area and etc.).

4- If the power supply needed for the building have the following requirements:

Supply types 100 % total power from the public grid; (Supplyof all installations and consumer Devices available in the building).

1030 % of the total power for safety power supply (SPS) fromgenerators; (Supply of life-protecting facilities in case of danger,e.g.: Safety lighting, Elevators for firefighters, Fire-extinguishingequipment).

520 % of the total power for uninterruptible power supply(UPS); (Supply of sensitive consumer devices which must beoperated without interruption in the event of a NPS failure / fault,e.g.: Tunnel lighting, airfield lighting, and Servers / computers andCommunications equipment).

Example for "Low building, type 2: Two supply sections " power system architecture:

We have a building with 2,400 KVA total load power, 4 floors and floor area 2,500 m2with total area 10,000 m2.

Solution selected for this building is using the Two supply section power systemarchitecture as follows:

Design solutionAdvantages of this

solutionBenefits from this

solution

Using Two supply sectionsper floor

Supply at the load center,short LV cables, low losses

Low costs, time savingsduring installation

Radial network Transparent structureEasy operation andfault localization

Transformer module with 2 1200 kVA,

Minimization of voltagefluctuations, lower staticsrequirements onbuilding structures

Optimized voltagequality, Costminimization in thebuilding construction


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work

Redundant supply unit: Generator 730 kVA (30 %)(the smaller the generator,the greater the short-circuit current mustbe compared to thenominal current) UPS 400 kVA (15 %)

Supply of importantconsumers on all floors inthe event of a fault, e.g.

during power failure of thepublic grid

Increased reliability ofsupply

Safety power supplySafety power supply inacc. With DIN VDE0100-718

Supply of sensitive andimportant consumers

Uninterruptible supplyofconsumers, e.g. duringpower failure of thepublic grid

Use Medium-voltageswitchgear from type SF6gas-insulated

Compact switchgear;independent of climate

Minimized spacerequirements forelectric utilities room;nomaintenance required

Use Transformer from typecast-resin with reducedlosses

Low fire load, indoorinstallation

Economical

Use Low-voltage maindistribution with centralgrounding point( whichsplitting of PEN in PE and Nto the TN-S system)

EMC-friendly power system

Protection fromelectromagneticinterference (e.g. topreventlower transmissionrates atcommunication lines)

Use Wiring / main route ascables

Central measurement ofcurrent, voltage, power,e.g. for billing, cost center

allocation

Cost transparency

Use Connection insidesubstation ( Transformer LVMD- NPS SPS) as busbars

Easy installation

For this example the power system architecture will be as follows:


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" Low building, type 2: Two supply sections " power system architecture

Where:

NPS Normal power supply

PCO Power company or system operator

FF Firefighters

HVAC Heating Ventilation Air

conditioningMS Medium-voltage switchboard

LVMD Low-voltage main distribution

SPS Safety power supply

UPS Uninterruptible power supply

z Power monitoring system
http://4.bp.blogspot.com/-qr0ZeIOulcQ/TzvgTSkymMI/AAAAAAAABK8/WJt667czSCQ/s1600/2.JPG


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electrical design philosophy for major types of buildings

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