Electrical

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TABLE OF CONTENT 1.0 Introduction 2.0 Electrical Supply System 2.1 Literature Review 3-4 2.2 Introduction 2.3 Case Study 2.3.1 TNB High Tension (HT) Room 2.3.2 Consumer High Tension (HT) Room 2.3.3 Vacuum Circuit Breaker 2.3.4 Transformer and Low Voltage Switch Room 2.3.5 Generator Set Room 2.3.6 Main Switch Board 2.3.7 Electrical Riser Room 2.3.8 Meter 2.3.9 Distribution Box 2.3.10 Lightings 2.4 Uniform Building By Law 2.5 Analysis & Suggestions 3.0 Fire Protection System 3.1 Literature Review 3.2 Introduction 3.3 Passive Fire Protection 3.3.1 Buffer Floor 3.3.2 Beams and Columns 3.3.3 Compartment Wall 3.3.4 Fire Emergency Room 3.3.5 Ventilation in Lift Shaft 3.4 Active Fire Protection 3.4.1 Fire Control Room 3.4.2 Water Tank 3.4.3 Fire Pump Room 3.4.3.1 Jockey Pump 3.4.3.2 Booster 3.4.3.3 Duty Pump 3.4.3.4 Standby Operation Pump 3.4.4 Wet Riser 3.4.5 Dry Riser 3.4.6 Fire Alarm 3.4.7 Fire/Smoke Detector 3.4.8 Sprinkler System 3.4.9 Carbon Dioxide Suppression System 3.4.10 Fire Extinguisher 3.4.10.1 Dry Powder Fire Extinguisher 3.4.10.2 Foam Fire Extinguisher 3.4.10.3 Carbon Dioxide Fire Extinguisher 3.4.11 Fire Roller Shutter 3.4.12 Fire Hydrant 3.5 Uniform Building By Law


4.0 Mechanical Transportation System 4.1 Literature Review 4.2 Introduction 4.3 Case Study 4.3.1 Machine/Control Room 4.3.2 Elevator 4.3.3 Fire Control Switch 4.3.4 Fire Fighter’s Elevator 4.3.5 Escalator 4.3.6 Inclined Moving Walkway 4.4 Uniform Building By Law 4.5 Analysis & Suggestions 5.0 Mechanical Ventilation & Air Conditional System 5.1 Literature Review 5.2 Introduction 5.3 Case Study 5.3.1 AHU Room 5.3.1.1 Air Handling Unit System 5.3.2 Fan Coil Unit 5.3.3 Chiller Room 5.3.4 Cooling Tower 5.3.5 Fan Room 5.3.6 Smoke and Heat Exhaust Ventilation System 5.4 Uniform Building By Law 5.5 Analysis & Suggestions 6.0 Conclusion 7.0 References


Abstract This paper is based on the research work of a commercial building, First Subang. This research draws upon mostly a complete collection of reviews, published articles and journals, observations and individual analysis. The fundamental purpose of this study is to identify the relationships between the components of a functional system in a building, which is relevant to electrical supply, mechanical ventilation and air-conditioning, fire protection system and mechanical transportation. This research is mainly for education purpose.

Acknowledgment We would like to take this opportunity to acknowledge the engineer, Mr.Bai who kindly assisted us during site visit and provided relevant information in this report. Doubtlessly to say, this report would not be finished on time without Mr.Adib’s guiding, so we would like to acknowledge Mr.Adib for the lecture slides and chary guiding along. Lastly, acknowledging the facilities manager who approved us for the site visit for First Subang on time, spending his precious time to guide us around in the building and access to authorized rooms, including explaining how the machines works in details.


1.0 Introduction

First Subang was developed by Titijaya Group, a property development company who in charged of E-Tiara projects. It’s situated right in the heart of the thriving SS15, Subang Jaya. It is a composition of retail area for the first 2 levels, and topped by two office towers. It consists 2 office towers on a retail podium made up of a basement, 5 floors of parking and 3 retail floors, including purpose-built supermarket, bank and restaurant which provides convenience to the residential users, though the AEON D’Hati Supermarket has occupied most of the space at lower ground floor. It has a total of 130 office suites in Southern Tower and Northern Tower. It’s situated within a high catchment financial and convention area, and easily accessible via 7 highways. The building is also broadband-ready, with available WiFi connection at the selected common areas. This report is to enhance our ability to understand the basic building services in a multi-storey building such as mechanical ventilation and air conditioning system, electrical supply system, mechanical transportation system and fire protection system.


2.0 Electrical Supply System 2.1 Literature Review

Energy has historically been made available for useful work by burning a fossil fuel such as coal or oil. Electricity constitutes a form of energy itself, which occurs naturally only in unusable forms such as lightning and other static discharges. The primary problem in the utilization of electric energy is that, unlike fuels or even heat, it cannot be stored and, therefore, must be generated and utilized in the same instant. This is the reason on why electricity has been playing a significant role in our daily life as a source of supply to provide mechanical ventilation and artificial lightings in the building. It is essential for modern living and business in the current society. There are 3 different branch of electrical supply companies in Malaysia that provides electric, which is the Tenaga Nasional Berhad (TNB) for peninsular Malaysia, Sabah Electricity Sdn. Bhd. (SESB) for Sabah and Sarawak Energy (SE) for Sarawak. These companies are important for all the occupants in Malaysia as they are the one providing and managing the daily electrical supply to all the household and commercial buildings. The electrical distribution system starts from the electric generating station, thermal power plant and hydro electric power plant. The electric will be distributed according to the ‘power distribution grid’, the amount of voltage distributed are depending on the amount of electrical appliances used by the building’s occupants. In the process of delivering the electricity to the users, which is also known as the power distribution grid, the voltage is expected to rise or drop depending on function and location. The amount of electric and the location of the building will affect the amount of voltage transferred. In the electrical supply system, the electric from the power generating station will pass through the step up transformer to increase the power, to save the use of limited source and to cover back the energy loss due to resistance of the lines. The high current produced enables the voltage to be transformed up to 132, 275 or 400kV for national transmission. Later on, the current will pass through the step down transformer where the current is brought down as the incoming current is too high for domestic purposes. And then the current is distributed to the facilities of the area around the substation based on the need of that certain building.


The electrical equipments and systems installed in the building are known as electrical distribution equipment. It is a necessary to do a thorough analysis and calculations on the amperage load and short circuit values of each individual part of the distribution system in order to achieve an efficient electric distribution system in the building.


2.2 Introduction First Subang Mall is a commercial building which requires more energy compare to the residential buildings. Hence, essential components like TNB high tension (HT) room, consumer high tension (HT) room, transformer & low voltage switch room, vacuum circuit breaker, generator and electrical riser room have to present in the building. Beside that, for safety purpose, emergency exit noticeboard and lighting are also applied in the building according to the Malaysia UBBL 1994 Law. Below that, each of the components will be explained more detailed and analyzed their actual functionality and practicality. These systems require a significant amount of space. Because much of these systems’ hardware is normally hidden from view-within concealed construction spaces or special rooms-the layout of these systems should be carefully integrated with each other.

Diagram 2.2 Circulation of Electrical System The diagram above shows overall circulation flow of an electrical system in First Subang, from TNB High Tension Room distribute to each individual electrical room. Details for each individual room system will be explain later on.


2.3 Case Study 2.3.1 TNB High Tension (HT) Room

Figure 2.3.1 Tenaga National Berhad High Tension Room

For the building which we are studying on, the First Subang Mall, is a commercial building which requires more energy compare to the residential buildings, therefore High Tension Room has to be designed in the building to split off the current and transfer to different step down transformers to reduce the amount of voltage and able to transfer them according to the usage needs for each individuals in the building. The electric supply is following the nation grid system, which is providing multiple paths between various generation sources and loads. Also, it transfers power from one geographic area to another to achieve overall system operating economics. Finally, it helps to interconnect the bulk power facilities of individual power station so they can better withstand major disturbances.


Diagram 2.3.1.1 Lower Ground Plan

As shown in Diagrams 2.3.1, the TNB High Tension Room is located at lower ground level, along the street, for easier accessibility by the authorized personnel, such as the electrical engineers from TNB. The TNB High Tension room here supplies electric power to First Subang Mall, as well as Empire Mall and Subang Parade.

Diagram 2.3.1.2 Elevation


2.3.2 Consumer High Tension (HT) Room

Figure 2.3.2 Consumer High Tension Room

The Consumer HT room is located next to the TNB HT room. The close proximity between these rooms ensure the prevention of loss and drop in current due to the resistance inside the electric cable. This is a room containing switch gears, it’s also known as “unit substation”. The current flows from the TNB High Tension room will be split and fed into different transformers in the Consumer High Tension room, each receiving 11kV and transform them to the Incomers and MSB. Their function is to step down the voltage so it will be safer to distribute depending on the usage of each department and facility in the building. The switchboards are all dead front, meaning, they all have circuit breakers, switches, fuses and live parts completely enclosed in a metal structure. Their durable grey finishing gives an aesthetic appeal and assisting wiring in dimly lit areas. Each step down transformers are functioning for different area, though all also step down the power to 2000kV first, one is for the landlord, one is for the tenants. Landlord referring to the public areas in the mall, like lift, car parks, toilets, where as the another one is for tenants who are living there, and last one is for the chiller. Various safety precautions have been taken here. There’s rubber mat placed on the ground near to the Main Switch Board. The purpose is to prevent the maintenance crew or authorized personnel from conducting earthling, therefore minimizing the chances of getting fatal electric shocks.


Diagram 2.3.2.1 Lower Ground Plan

Consumer High Tension(HT) Room is located next to TNB High Tension(HT) Room as if break down of electrical supply occurs, maintenance checked can be done at Consumer HT Room and TNB HT Room at the same time.

Diagram 2.3.2.2 Elevation


2.3.3 Vacuum Circuit Breaker

Figure 2.3.4 Vacuum Circuit Breaker

A circuit breaker is an electromechanical device that performs the same protective function as a fuse and also acts as a switch. When an unexpected high surge of current issued, these breakers will use high density air to break the circuit from causing any unnecessary damage to the main switch boards thereby prevent power surges and fires. It breaks the circuit quicker than fuses, which is why fuses are normally used in lower voltage electrical equipment whereas vacuum circuit breaker are used in high tension room. In a vacuum circuit breaker, there’re two electrical contacts are enclosed in a vacuum. One of the contacts is fixed and one is movable. When the circuit breaker detects a dangerous situation, the movable contact pulls away from the fixed contact, interrupting the current. Because the contacts are in a vacuum, arcing between the contacts is suppressed, ensuring that the circuit remains open. As long as the circuit is open, it will not be energized.


2.3.4 Generator Set Room

Figure 2.3.4 Generator Set Room

When there is a breakdown in power supply from the TNB, the generator in Generator Set Room will be generating electricity for the building until the power supply has been regained. The generator act as a backup electric supply source when there’s a electrical shortage from the main power supply from Tenaga Nasional Berhad. However, this power supplied by generator will only be enough for the lightings which are directly connected, such as lift, lobby and toilet, but would not be supplying for the tenants' offices due to shortage of electricity supplied.


Figure 2.3.4.1 Electric Generator Set

The engine generator set comprises of three components which are fuel systems, the body set, and the exhaust facilities. The noise produced by the generator during maintenance and regular testing are extremely loud, but there’s a big fan operating to cool the generator as well which will be explained later on.

Figure 2.3.4.2 Nickel Cadmium Battery

The core of the generator is nickel cadmium battery, it’s the starter of the machine, . The nickel cadmium battery is a type of rechargeable battery using nickel oxide hydroxide and metallic cadmium as electrodes.


Figure 2.3.4.3 Diesel Fuel Tank

Battery has much lower specific energy than the fuel such as gasoline, therefore the diesel fuel is required for the workout of the generator while still using battery to operate, even though the gasolines can only be stored for a year at most, and disposal is difficult. The diesel fuel passes through the motor and allow combustion to occur. At this stage, the dynamo will generate electric field and current will be channeled to the LV Room followed by the distributing areas.


Figure 2.3.4.4 Radiator Cooling Generator Set

As the generator will be generating heat as well while generating electricity, precautions of preventing over heating and fire from occurring have been taken. There’s radiator cooled diesel engine generator set allocated right next to the generator to extract heat from the engine and pumped outside. The radiator cooling system is made up of tubes surrounded by fins.

Figure 2.3.4.5 Fresh Air Intake

Above the entrance of the generator set room, there’s a air fin to allow the air enter while still able to filter out the unwanted dust though the mesh to allow more ventilation for cooling the room. Ventilation is very important especially when the generator is operating due to the heat it produced.


Diagram 2.3.4.1 Ground Floor Plan

Generator Set Room is located above all of the other electrical rooms as the generator itself produces more heat compared to the others and so a higher location is ideal for better ventilation compared to basement and ground floor that is more stuffy.

Diagram 2.3.4.2 Elevation


2.3.5 Transformer and Low Voltage Switch Room

Figure 2.3.5 Transformer

The stepped down current from each transformer is transferred to their own respective Main Switch Boards (MSB) in the Low Voltage Room. In First Subang, there are 3 MSBs for landlord, tenant and chiller. These panels are the main power switches of the entire building, one is for the landlord, one is for the tenants and the other one is for chiller. Landlord referring to the public areas in the mall, like lift, car parks, toilets, where as the another one is for tenants who are living there. Similarly, these panels are set back from the wall to allow maintenance from the engineers. The room is extreme hot due to the heat generated by the passage of current through transformer coils due to the winding cable resistance. Therefore, extra fan is placed in the room.


Diagram 2.3.5.1 Basement Plan

Transformer Room is located one floor below Consumer High Tension(HT) Room and TNB High Tension(HT) Room as distribution of electricity can be transferred quicker through the electrical circuits in between these rooms.

Diagram 2.3.5.2 Section


2.3.6 Main Switch Board (MSB)

Figure 2.3.6.1 Main Switch Board

An electric switchboard is a device that directs electricity from one or more sources of supply to several smaller regions of usage. It is an assembly of one or more panels, each of which contains switches that allow electricity to be redirected. Switchboards consist of various electronic apparatus used to operate electric circuits. The function of a switchboard is to transmit electricity from one source to another. Normally, high voltage appliances such as lifts and elevators take their powers directly from sub-switch board whereas the low voltage appliances such as lightings are to be managed by distribution board. In other words, SSB controls high power facilities, where as the lightings go under distribution Board.

Figure 2.3.6.2 Sub Switch Board


2.3.7 Electrical Riser Room

Figure 2.3.7 Electrical Riser Room (Source: Estana Court 2014)

A riser room is where the electrical distribution equipment (Switchgears and Panels) that supplies the electrical systems of the building is located. Electrical conduits that feed the various equipment, A/C units and sub panels and fire pumps originate here.


2.3.8 Electric Meter

Figure 2.3.8.1 Electric Meter

The electric meter is an instrument that measures the amount of electric energy used by a consumer in a house, shop, offices etc. It is calibrated in kilowatt-hours. One kilowatt-hour is the amount of electric energy required to provide 1,000 watts of power for a period of one hour. The amount of electric meter in a building depends solely on the number of tenants at each floor. For most domestic electric meter it is usually enclosed in a glass case which contains a revolving disk which in turn rotates a series of numbers or dials. When the electric current passes through the meter, the disk rotates to measure the exact amount of kilowatts used whenever there is electric current that pass through the meter. The speed of rotation varies depending on how much electricity the user is using in that building for particular device such as running a washing machine, microwave and water heater etc. It is important to note that different electric appliance uses different amount of electricity for its operating.

Figure 2.3.8.2 Meter

There are meters for each sub station in First Subang as shown in figure 2.3.8.2.


Diagram 2.3.8 Lower Ground Floor Plan

As shown in diagrams 2.3.8, the meter room is situated nearby the switching room and and the previous electricity room, this is for ease of checking by the maintainers from the building and TNB. Easy access for meter checking regularly by the TNB maintainers as well to check no problem occur on the meter.


2.3.9 Distribution Room

Figure 2.3.9 Distribution Board

After passing through the electric meter, the electricity will be diverted to the distribution board which will be located inside the electric room. The distribution board is also known as panelboard or breaker panel. The main function of the distribution board is to divide the electrical power feed into subsidiary circuits while providing a protective fuse or circuit breaker for each circuit. The distribution board offers protection to users and equipment from electrical shock or fire resulting from ground faults. The electricity from the distribution board is then further delivered to Miniature Circuit Board(MCB) and Earth Leakage Circuit Board(ELCB).

Figure 2.3.9.1 Distribution Board wiring


Diagram 2.3.9.1 Ground Level Plan

As shown in diagrams 2.3.9, the meter room is situated in the building passageway for easy access for the maintenance on fuse and circuit breaker if necessary. The passageway is narrow and hidden so the normal users in the mall are less likely to use that path, as it’s meant for the maintainers.

Diagram 2.3.9.2 Elevation


2.3.10 Lighting

Diagram 2.3.10 Lighting Distribution The diagram 2.3.10 shows one of the distribution of electric to the lightings in First Subang. The type of light bulb used in the down lights in the building is the compact fluorescent light bulbs. Most commercial buildings use this type of lightings as it offers long life and high quality energy efficient task lighting. The lighting portion of the bulbs are normally a small tube structure, either in parallel form or in a swirled shape. Though the usage of lightings might seem a lot in the plan but they are all placing along the path after calculating the distance and their range of coverage, so the whole circulation path would be bright enough for the occupants’ comfort level.


2.4 Uniform Building By Law ď Ź

Section 240 (1) Every floor or zone of any floor with a net area exceeding 929 square meters shall be provided with an electrical isolation switch located within a staircase enclosure to permit the disconnection of electrical power supply to the relevant floor or zone served. (2) The switch shall be of a type similar to the fireman's switch specified in the Institution of Electrical Engineers Regulations then in force.

ď Ź

Section 241 In places where there are deaf persons and in places where by native of the occupancy audible alarm system is undesirable, visible indicator alarm signals shall be incorporated in addition to the normal alarm system.

Whereas according to Electricity Supply Act 1997 [Act 447] P. U. (A) 38/94 Electricity Regulations 1997, it is listed that: Regulation 15, Apparatus, conductor, accessory, etc. Any conductor or apparatus that is exposed to the weather, water, corrosion, under heating or use in inflammable surroundings or in an explosive atmosphere shall be constructed or protected in such a manner as to prevent danger. Regulation 16, Switch, switch fuse, fuse switch, circuit breaker, contractor, fuse, etc. Any fuse or circuit breaker shall be: (1) Constructed and arranged in such a manner so as to break the current when it exceeds a given value for such a sufficient time to prevent danger (2) Constructed guarded or placed in a manner as to prevent danger or overheating, arcing or from the scattering of hot metal or other substances or enclosure.


2.5 Analysis & Conclusion

The Cardio-Pulmonary Resuscitation(CPR) board is placed in each electrical room for safety purpose. The board provides information to prevent apparent death from electric shock as emergency procedure can be performed in an effort to manually preserve intact brain function in a case that a person is unresponsive with abnormal breathing. Even though there’s a board in every electrical room to guide the people during emergency situation, however, this is still not considerate enough especially for the OKU people. According to UBBL, visible indicator alarm signals did not use in First Subang and create danger to the deaf people. Although deaf people isn't the main group among the users, they still exist in the building and rely on the system. Hence, First Subang should consider more on the OKU people since it's a commercial building. In conclusion, electric supply system in First Subang is quite complete since it fulfill most of the Uniform Building By Law's requirements. All kind of users and it will cause trouble in special case. A good system should consider every users and fulfill their needs. Hence, local authority should enhance the system and regularly check all the components' availability.


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