NESPAK Internship Report

8/10/2019 NESPAK Internship Report

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Internship Report

Electrical Section

Zain AlamThird Year BE (Electrical)

Bearing Roll No.: EE-072NED University of Engineering & Technology. Karachi

Internship Duration: 19th

of May to 27th

of June,2014

This report summarizes the work completed on all major projects assigned during the time spent at

NESPAK. The project work completed covers a wide range of engineering applications from the

electrical design of different projects to configuring networks.


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Abstract

National Engineering Services Pakistan and NED University have a strong relationship, and as

a result a selection of students studying their third year of Engineering have the opportunity

to complete an internship at the NESPAK design firm, located in Karachi. The purpose of this

report is to present the work completed on assigned projects during the internship.

In order to provide a substantial contribution to the project work, an understanding of the

designing processes and operations, overall lighting design and power layout and software

and design suites utilised by engineers on site was required. A summary of this background

information is detailed within this report.

This report summarises the work completed on all major projects assigned during the time

spent at NESPAK. The project work completed covers a wide range of engineering

applications from the electrical design of different projects to configuring networks. A

contribution has been made to several projects which are listed within the report. Some

projects will be covered in greater detail, highlighting required background information,

methodologies applied, project constraints and a description of the projects` outcomes. The

following projects to be discussed in greater detail are as follows:

New Benazir Bhutto International Airport, Islamabad

New Gawadar International Airport, Gawadar

Emaar-Cresent Bay

Mukhtar A.Sheikh Memorial Hospital, Multan

This report will also cover the work on the some small projects and additional work

completed outside of the assigned projects.

The internship allows the student to gain experience with industrial projects that consulting

engineer is involved with on a daily basis, creating an invaluable learning experience. This

will help the student apply the knowledge gained from university and to develop skills

needed for the workplace personally and professionally.


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Acknowledgments

I would like to thank National Engineering Services Pakistan Pvt. Ltd and NED University of

Engineering & Technology for providing me the opportunity to complete an internship with

their consulting engineering group. This internship has given me the chance to be involved

with first hand, real world Electrical design engineering projects.

My sincere gratitude is expressed towards the entire consulting group at the NESPAK. Their

guidance and relentless assistance has contributed greatly to the success of this internship.

First of all my gratitude is towards General Manager Electrical Section Engr. Rabia Bolani.

Then my gratitude is towards Senior Engr.Rabia Hasan, Engr.Sarah Amjad, Engr.Noman for

explaining us the details of communication systems in buildings, Sub Engr.Waqas for guiding

us to learn AutoCAD, Mr.Haris for guidance about CV writing and system of the organization,

and all the other professional who have helped us by giving us their kind attention and

support.

Thanks should be reserved for all the staff at NED University who have been involved with

my learning during my degree. Special thanks is required for Internship Advisor Mr.Abdul

Mateen who has overseen the internship with ongoing support and direction. All Professor

Associate Professor should also be regarded for their substantial contribution towards my

learnings at university.


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Structure of Report:

The report is categorized into three parts. First part tells about the organization

structure, field of specification and its working. The second and the most important part

consists of the stuffs and assignment that we go through the period of our internship and

the third and last part is the conclusion of the report.

Introduction to the organization

Internship work

o Electrical work

Project Hierarchy

Site engineering work- Project Procedure

Types of lights

Power load calculation

Lighting load calculation

Electrical Grounding

Grounding pit

Electrical conduits

Implementation of above techniques in sites

Phase reversible changeover switch

o Communication work

Conclusion


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Introduction To Organization:

The National Engineering Services Pakistan(reporting name: NESPAK), is amultinational and

globally competitivestate-owned enterprise ofGovernment ofPakistan. It is one of the largest and

one of the apex engineering consultant management organization in Asia and Africa, and maintains a

well international reputation.

Services Of NESPAK:

NESPAK has been performing projects under the following categories since many years:

Energy Sector

Water Resources Development & Dam Engineering Sector

Communication Sector

Architecture & Planning Sector

Public Health Engineering Sector Industrial Sector

Oil,Gas & Petrochemical Sector

Environment Sector

Information Technology & GIS

PROJECT HIERARCHY:

Project is basically an individual or collaborative enterprise that is carefully planned to achieve a

particular aim.Project to be processed owns by a client,it first comes to the consultant for designing

the structure,lighting layouts,power layouts,etc.The Consultant helps clients to identify and define

operational issues, then develop and implement operational strategies to improve organizationaleffectiveness and achieve positive bottom line results.This is the focal role within the Firm for the

delivery of business services to clients.Role of consultants basically for engineering projects are Civil

work including Architecture,Mechanical work including HVAC,Electrical work including cable sizing

and much more.Now after design work,projects goes to the contractors.Contractor is a person or

firm that undertakes a contract to provide materials or labour to perform a service or do a

job.During contracting process,someone has to offer materials for the installation in the project and

that someone is a vendor. Vendor is a person or company offering something for sale.

Electrical projects includes three categories:

HT Requirements

It includes all the equipments required for 132kV,66kV,11kV,surge arrestors,tc.

LT Switch

It includes equipments like transformers,generators,lighting,power,DBs,MCCs,earthing

lightning protection,etc.

Communication

It includes equipments for fire alarm,public addressing,CCTV for security,BMS(Building

Management System),etc.
http://en.wikipedia.org/wiki/Reporting_namehttp://en.wikipedia.org/wiki/Multinational_corporationhttp://en.wikipedia.org/wiki/Category:State_corporations_of_Pakistanhttp://en.wikipedia.org/wiki/Government_of_Pakistanhttp://en.wikipedia.org/wiki/Pakistanhttp://en.wikipedia.org/wiki/Pakistanhttp://en.wikipedia.org/wiki/Government_of_Pakistanhttp://en.wikipedia.org/wiki/Category:State_corporations_of_Pakistanhttp://en.wikipedia.org/wiki/Multinational_corporationhttp://en.wikipedia.org/wiki/Reporting_name


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Site Engineering Work - Project Procedure

(Explained by Mr.Qazi)

There are 3 main things:

Contractors time schedule.(1st

step)

It is checked out if BOQ, activities, etc are right or not.

Contractor approves submittevs.(2nd

step)

It is send to head office.

Shop drawing is approved.(3rd

step)

Shop drawing is very important.

There are 2 drawings: tender drawing, construction drawing.

Then site visit is done.

There is a weekly/ fortnightly meeting at site.

There is marking by surveyor at locations for fitting things.

EARTHING OF A APARTMENT BUILDING

In electricity supply systems, an earthing systemor grounding system is circuitry which connects

parts of the electric circuit with the ground, thus defining the electric potential of the conductors

relative to the Earth's conductive surface.In high rise structures this technique is very essential to

ensure the safe existance and relaibility of the tower or structure against the lightning surges, for

this we maintain the lighting protection system. This system is protect the electrical circuitry from

excessive power surges or from thunder lighning energy.

Lightning Energy

Lightning is a capricious, random and unpredictable event. Its physical characteristics include current

levels sometimes in excess of 100 kA and speeds approaching one third the speed of light. Globally,

some 2000 on-going thunderstorms cause about 100 lightning strikes to earth each second.


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Lightning is a product of electrically charged storm clouds. The charged clouds induce an opposite

charge (ground charge) on the surface of the earth beneath it as they travel through the

atmosphere. When the ground charge reaches a structure, the cloud charge pulls it up onto the

structure, concentrating the ground charge on and around it. If the ground charge builds to a level

exceeding the dielectric (insulation resistance) of the intervening air, an arc or lightning strike will

occur. The process begins with stepped leaders branching down from the clouds. When they comewithin close proximity to the ground, approximately 500 feet, the electric field intensity at ground

level becomes so strong that objects and structures begin to break down electronically, shooting

streamers up toward the stepped leaders. When a streamer and a stepped leader connect, a path is

created for a lightning strike.

To protect the buildings or telecommunication towers against lightning, a proper designed lightning

protection system is needed.

Conventional Lightning Protection System

The main function of the lightning protection system installed on the existing building is to capture a

lightning stroke and then conduct discharge current safely to the ground.

As shown above, the building requires number of copper rods, number of down conductors, number

of earth pits, maintenance of all this put together becomes a costly & wastage of time also. In some

conditions, however the active lightning system is the only possible method to protect from direct

lightning strokes. Due to the arguments mentioned above, we recommend to use the active

lightning protection whenever the conventional solution is inconvenient or when the former is more

preferable to the latter as in the case of the efficient protection of architect.

STORMASTER Early Streamer Emission Air Terminal

Stormaster Early streamer Emission air terminals are designed to emit a streamer early in the

streamer-formation phase of a lightning strike, thereby

becoming the preferred lightning attachment point.

As the ground charge builds immediately before the

lightning strike, the Stormaster ESE air terminal accumulates

ground charge. In the instant before the strike, when the

stepped leaders are branching down from the cloud, the

Stormaster ESE terminal emits a series of pulses of ground

charge, forming a streamer from itself before streamers

emit from other structures. Its streamer reaches thestepped leaders before competing streamers, thereby


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winning the competition. Ground charge accumulation and streamer triggering is done by LPIs

Stormaster ESE Air Terminal.

LPI Early Streamer Emission Air Terminal

LPIs reputation in the field of lightning has invested heavily in the manufacture of its STORMASTER

Early Streamer Emission Air Terminal. This has involved both fundamental research into the physical

phenomena associated with lightning, as well as extensive product development. The latest

STORMASTER series provides optimal protection against the direct effects of lightning.

LPI STORMASTER ESE terminals tested

as per NFC 17-102 (national French

Standards) & IEC 60-1:1989 standards.

LPI advance lightning protection system

not only specialized on the Airterminals, we execute the total project

with the specialized down conductor

named HVSC (High Voltage Shielded

Cable) tested as per IEC standards in

High Voltage testing laboratories. HVSC (Down Conductor) enables the customer use inside the

building, safely routed in Oil sectors, IT sectors & it provides tension free from the electromagnetic

damages created by the Lightning current when it is grounded through the normal down conductor.

LPI offers the non-resettable Lightning Strike Recorder which enables the user to have fool proof

record of the proper functioning of the system. Last but not least, LPI offers the latest technology of

Chemical Gel Earthing (GRIP Ground Resistance Improvement Powder) which dissipates the huge

amount of lightning current in a fraction of time thus avoiding the huge potential rise under theground. The glance of LPI STORMASTER protection level is shown below:

Standard Protection (Level-3) - Radius of Protection (Rp)

h = height of terminal above area to be protected (m) 2

Stormaster 60 44 87 107 109

Stormaster 50 38 76 95 98



Components of a lightning protection system

Lightning rods or 'air terminals' are only a small part of a complete lightning protection system. In

fact, the rods may play the least important role in a system installation. A lightning protection

system is composed of three main components:

1. Rods or 'Air Terminals'- The small, vertical protrusions designed to act as the 'terminal' for a

lightning discharge. Rods can be found in different shapes, sizes and designs. Most aretopped with a tall, pointed needle or a smooth, polished sphere. The funtionality of different


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types of lightning rods, and even the neccessity of rods altogether, are subjects of many

scientific debates.

2. Conductor Cables - Heavy cables (right) that carry lightning current from the rods to the

ground. Cables are run along the tops and around the edges of roofs, then down one or

more corners of a building to the ground rod(s).

3.

Ground Rods- Long, thick, heavy rods buried deep into the earth around a protectedstructure. The conductor cables are connected to these rods to complete a safe path for a

lightningdischarge around a structure.

The conductor cables and ground rods are the most important components of a lightning protection

system, accomplishing the main objective of diverting lightning current safely past a structure. The

'lightning rods' themselves, that is, the pointy vertically-oriented terminals along the edges of roofs,

do not play much of a role in the functionality of the system. A full protection setup, given good

cable coverage and good grounding, would still work sufficiently without the air terminals.

Lightning protection facts

Rods and protection systems don't attract lightning, nor do they influence where lightning

will strike.

Rods or protection systems do not and cannot prevent lightning, nor can they 'discharge'

thunderstorms.

Lightning protection systems (including placement of rods, cables, and groundings) are

custom-designed for individual structures and require complex engineering to function

properly. They should only be installed by qualified contractors.

Lightning protection systems do not always prevent damage to electronics or computers.

You should still unplug such devices during thunderstorms to ensure sufficient protection.

Types Of Lamps

Definition:

Phenomenon of light exhibit by certain crystalline material when previously absorb energy from

heating of material.

There are three basic principle of lamps

1.

Halogen lamp

2. Flourescent lamp

3. LEDs

Halogen Lamps

A lamp that consist of small amount of halogen such as iodine,bromine.When heated tungsten and

iodine combines to form tungsten iodine, which redeposits tungsten back to filament.

Advantage

1. Life is increased

2. efficiency is increased

Fluorescent Lamps
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Electric current excites mercury vapor which produce short wave U.V light which is converted into

visible light through phosporous.

LED Lights

When current flows in led, electron recombines with holes within the device, releasing energy inform of photons.

Effect is called electro lumiscence and color of light is determined by energy band gap.

Earthing Of An Apartment Building

In electricity supply systems, an earthing system or grounding system is circuitry which connects

parts of the electric circuit with the ground, thus defining the electric potential of the conductors

relative to the Earth's conductive surface. In high rise structures this technique is very essential to

ensure the safe existance and relaibility of the tower or structure against the lightning surges, for

this we maintain the lighting protection system. This system is to protect the electrical circuitry from

excessive power surges or from thunder lightning energy.

Lightning Energy

Lightning is a capricious, random and unpredictable event. Its physical characteristics include current

levels sometimes in excess of 100 kA and speeds approaching one third the speed of light. Globally,

some 2000 on-going thunderstorms cause about 100 lightning strikes to earth each second.Lightning

is a product of electrically charged storm clouds. The charged clouds induce an opposite charge

(ground charge) on the surface of the earth beneath it as they travel through the atmosphere. When

the ground charge reaches a structure, the cloud charge pulls it up onto the structure, concentrating

the ground charge on and around it. If the ground charge builds to a level exceeding the dielectric

(insulation resistance) of the intervening air, an arc or lightning strike will occur. The process beginswith stepped leaders branching down from the clouds. When they come within close proximity to

the ground, approximately 500 feet, the electric field intensity at ground level becomes so strong

that objects and structures begin to break down electronically, shooting streamers up toward the

stepped leaders. When a streamer and a stepped leader connect, a path is created for a lightning

strike.To protect the buildings or telecommunication towers against lightning, a proper designed

lightning protection system is needed.

Conventional Lightning Protection System

The main function of the lightning protection system installed on the existing building is to capture a

lightning stroke and then conduct discharge current safely to the ground.The building requires number of copper rods, number of down conductors, number of earth pits,

maintenance of all this put together becomes a costly & wastage of time also. In some conditions,

however the active lightning system is the only possible method to protect from direct lightning

strokes. Due to the arguments mentioned above, we recommend to use the active lightning

protection whenever the conventional solution is inconvenient or when the former is more

preferable to the latter as in the case of the efficient protection of architect.

Components Of A Lightning Protection System

Lightning rods or 'air terminals' are only a small part of a complete lightning protection system. In

fact, the rods may play the least important role in a system installation. A lightning protectionsystem is composed of three main components:


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Rods or Air Terminals - The small, vertical protrusions designed to act as the

'terminal' for a lightning discharge. Rods can be found in different shapes, sizes and

designs. Most are topped with a tall, pointed needle or a smooth, polished sphere.

The functionality of different types of lightning rods, and even the neccessity of rods

altogether, are subjects of many scientific debates.

Conductor Cables- Heavy cables (right) that carry lightning current from the rods tothe ground. Cables are run along the tops and around the edges of roofs, then down

one or more corners of a building to the ground rod(s).

Ground Rods- Long, thick, heavy rods buried deep into the earth around a

protected structure. The conductor cables are connected to these rods to complete

a safe path for a lightningdischarge around a structure.

The conductor cables and ground rods are the most important components of a lightning protection

system, accomplishing the main objective of diverting lightning current safely past a structure. The

'lightning rods' themselves, that is, the pointy vertically-oriented terminals along the edges of roofs,

do not play much of a role in the functionality of the system. A full protection setup, given good

cable coverage and good grounding, would still work sufficiently without the air terminals.

Lightning Protection Facts:

Rods and protection systems don't attract lightning, nor do they influence where lightning

will strike.

Rods or protection systems do not and cannot prevent lightning, nor can they 'discharge'

thunderstorms.

Lightning protection systems (including placement of rods, cables, and groundings) are

custom-designed for individual structures and require complex engineering to function

properly. They should only be installed by qualified contractors.

Lightning protection systems do not always prevent damage to electronics or computers.

You should still unplug such devices during thunderstorms to ensure sufficient protection.

Residential Load Estimation:

We made calculation of all lights installed in our homes and also determined the energy

consumption of other small and heavy loads. We found wattage of each and every equipment like

tubelights, savers, fans, AC, water electric heater, dispenser, etc. then calculated their usage

duration per day and then determined power capacity of all load per day in kW.
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Hospital Sockets Calculation

We were given Mukhtar A.Sheikh Hospital, Multan which came to NESPAK for designing . We

determined the different types of sockets after calculating the power capacity of every equipments

for installation in the hospital. We have been given a list of equipments including motorized patient

bed, patient monitor, tv, fridge, laser unit, auto clave, dental chair, etc. we searched wattages of all

equipments listed in a sheet we were given, and then found different sockets like 16A,250 V,2 PINB

EARTH,SINGLEX AND DUPLEX SCHUKO OUTLET, 15A 250 V 3 PIN SWITCH SOCKET OUTLET, etc as per

wattages of equipments.


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Site 616 Karachi:

In this project,we determined number of lights and also their types to be installed in every room of

site 616.For example we set 300 lux in office type rooms,150 lux in sailor type rooms,50 lux in wash

and toilets.According to this calculation,we placed the required no.of lights through diaLUX

software. Through this task,we got a chance to learn diaLUX and many other little things.

Electrical conduit:

An electrical conduitis a tubing system used for protection and routing ofelectrical wiring.Electrical

conduit may be made of metal, plastic, fiber, or fired clay. Flexible conduit is available for special

purposes.

Conduit is generally installed byelectricians at the site of installation of electrical equipment. Its use,form, and installation details are often specified by wiring regulations, such as the USNational

Electrical Code (NEC) or other national or local code. The term "conduit" is commonly used by

electricians to describe any system that contains electrical conductors, but the term has a more

restrictive technical definition when used in official wiring regulations

Comparison with other wiring methods:

Electrical conduit provides very good protection to enclosed conductors from impact, moisture, and

chemical vapors. Varying numbers, sizes, and types of conductors can be pulled into a conduit, which

simplifies design and construction compared to multiple runs of cables or the expense of customized

composite cable. Wiring systems in buildings may be subject to frequent alterations. Frequent wiring
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changes are made simpler and safer through the use of electrical conduit, as existing conductors can

be withdrawn and new conductors installed, with little disruption along the path of the conduit.

Cable tray

In theelectrical wiring of buildings, a cable traysystem is used to support insulated electriccables

used for power distribution and communication. Cable trays are used as an alternative to open

wiring orelectrical conduit systems, and are commonly used for cable management in commercial

and industrial construction. They are especially useful in situations where changes to a wiring system

are anticipated, since new cables can be installed by laying them in the tray, instead of pulling them

through a pipe.

Types

Several types of tray are used in different applications. A solid-bottom tray provides the maximum

protection to cables, but requires cutting the tray or using fittings to enter or exit cables. A deep,

solid enclosure for cables is called a cable channel or cable trough.[1]

A ventilated tray has openings in the bottom of the tray, allowing some air circulation around the

cables, water drainage, and allowing some dust to fall through the tray. Small cables may exit the

tray through the ventilation openings, which may be either slots or holes punched in the bottom. A

ladder tray has the cables supported by a traverse bar, similarly to the rungs of a ladder, at regular

intervals on the order of 4 to 12 inches (100 to 300 mm).

Ladder and ventilated trays may have solid covers to protect cables from falling objects, dust, and

water
http://en.wikipedia.org/wiki/Electrical_wiringhttp://en.wikipedia.org/wiki/Cablehttp://en.wikipedia.org/wiki/Electrical_conduithttp://en.wikipedia.org/wiki/Cable_tray#cite_note-Steward10-1http://en.wikipedia.org/wiki/Cable_tray#cite_note-Steward10-1http://en.wikipedia.org/wiki/Cable_tray#cite_note-Steward10-1http://en.wikipedia.org/wiki/Cable_tray#cite_note-Steward10-1http://en.wikipedia.org/wiki/Electrical_conduithttp://en.wikipedia.org/wiki/Cablehttp://en.wikipedia.org/wiki/Electrical_wiring


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CABLE LADDER:

Ladder is more suitable for more and larger cables than tray. We use it for cables stiff enough tosupport their own weight between rungs. It is used for low and medium voltage. It has the

advantage of less dust sitting on it.

GROUNDING REQUIREMENT OF POWER HOUSE:

Electrical grounding has two function,(earthing) and a (bonding function)

FUNCTION OF ELECTRICAL GROUNDING:

A major purpose of grounding is to provide a path so a short will trip a breaker,thatrequires a low

resistance path back to the power source which is the utility transformer path relies on a neutral

ground connection required at all services.

The second grounding fuction is actually the collection of three safety function

Minimize voltage between exposed metal and earth

Minimize the voltage between the power wires and earth

Provide a sink for lightning,power line crosses,and similar hazards

Required for safety ,lest fuses blow

Some discussion are given below:

Example: toaster falls into metal sink

House plumbing(grounds the plumbing)

Entering metal water pipe (grounds the system)

Grounding electrode(2 now recommended)

Continuous, no splices, water bypass

Copper ground wires and grounding conductor(corrosion resistant)

Al insulated solid conductor

Al insulated multistrand Al bare vs insulated(risk of corrosion, break in wire, loss of safe grounding)


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WHAT IS ELECTRICAL BONDING. WHY IS IT IMPORTANT?

The path from ground conductor(which is not necessarily a wire) to the service panel through the

neutral ground connection and back to the transformer via the service neutral. To provide highcurrent to trip a breaker this must be a metal path

The earth is not too far high in electrical resistance and is not allowed to be the path. In fact, this

function will work if the service is not connected to earth. This function might best be called

bonding.

Connecting exposed metal together to minimize voltage between surfaces is also a bonding function.

STEPS FOR DESIGNING THE GROUNDING SYSTEM OF A BUILDING:

STEP 1:A soil resistivity test is performed to detrrmine the soil resistivity profile and the soil model needed.

STEP 2:

The conductor size is determined considering the max possible expected current that can flow in the

system.

STEP 3:

Tolerable touch and step voltages are determined.

STEP 4:

A conductor loop should surround the entire grounded area plus adequate cross conductors areprovided for convenient access for equipment.

STEP 5:

Computer analysis is performed to compute the resistance of the equipments of the grounding

system with a higher degree of accuracy.

STEP 6:

If the touch voltages, GPR and step voltages are within tolerable limits, the desighn is successful. If

not, the desighn has to be revised.

STEP 7:If revision is required, it may include additional ground rods, smaller conductor spacing, additional

ground rods may be required at base of surge arrestors, transformer neutrals, etc.

GROUNDING REQUIREMENT OF ANY SERVICE BUILDING EQUIPMENT:

All electrical equipments require grounding. There are 2 types of grounding requirements of a

building:

1) For neutral grounding

2)

For body grounding


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NEUTRAL GROUNDING:

In this, we ground the neutral so as to make the neutral at zero voltage level. This is done for three

phase machines such as 3 phase motors. The methods for neutral grounding are:

1) Solid grounding

2)

Resistance grounding3) Resonance grounding

4) Grounding through earthing transformer

1) SOLID GROUNDING:

In this, a wire is used for grounding. This has the disadvantage that high current flows in case of

fault and when the breaker is tripped, it is tripped for a long time. It is used for


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Uses:

It is use for lightning/motor circuits wherever continuity of supply is necessary for switching andalternative source from main supply and vice versa they are switch disconnectors for independent

manual operation capable of making, breaking & carrying current, under normal circuit conditions

which may include operation overload conditions & specified abnormal conditions such as short

circuit.

Contact mechanism:

It is knife blade type self-cleaning action during operation. The fixed contact terminals in each phase

have separate main and arcing contents

Construction:


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It has a unique modular construction. It consist of 2 load switches and disconnectors coupled

together and mechanically interlocked with a common outgoing and operable by signal handle

having 1-0-11 position.

Communication:

Explained by Engr.Noman

Some main points are given below:

Structure cabling is use in CCTV internet etc. cross cable is used for communication between

computers.

There are 2 points in a workplace, one for telephone and the other for network.

NTC gives telephone lines in government organization while PTCL gives in private organization.

PABX stands for private automatic branch exchange. For using more computer on few lines for

telecommunication.

PRI stands for primary rate interface.

BRI stands for binary rate interface.

Office cabling:

1. Structured cabling network

2.

Fire alarm system

3. CCTV system

4. Public address system

5.

Access control system

6.

CATV system

Airport:

1. Flight information display system

2.

X-ray baggage machine

3.

Master clock system

Hospital:

Nurse call system.

Jacks:

There are 2 jacks


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1.

Telephone jack: RJ-11 (Registered Jack 11)

2.

Data jack: RJ-45

Office lines:

1.

Extension point2.

Direct line (has a dedicated number)

3. Fax line

4. Hot line: used at very large level and very seldom. It works through all wireless, wired ways

etc.

5. Parallel line

6. Steno line: it doesnt goes directly to high official

CAT cables:

CAT-1 to cat-7

CAT-6.7 is normally used.

Cat-3 and 5 are the backbone cables. They are used between DB to DB connections while CAT-

1.2.3.4 is obsolete.

OLT stands for optical line terminal

At every 100 sq.ft. 1 telephone and one data and 2 power points are given.

For designing a telecommunication system, a head equipment is made

BD stands for building distributor while FD stands for floor distributor.

CCTV cameras:

They are of 2 categories

1.

General monitoring

2. Security

They are of 2 types

1.

IP

2.

Conventional

They can be of the following forms

1.

Fixed dome/box camera (it cannot move and is used as at entrance and exit)

2.

Pts. dome camera (pan tilt zoom)

3. Thermal camera: used in outer premises it captures heat.

4. Artificial intelligence camera: it is expensive. If someone goes the wrong way it beeps.

Types of lenses:

1. Fixed lens


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2.

Vary focal lens (it can zoom in/out)

3.

Zoom lens (it can zoom very much)

FOH stands for field of horizontal

DTO stand for distance to object.

BMS stands building management system.

After 90m one cannot extend copper telecommunication cable.

Fiber optics cable:

1. Single mode (5 till 80 km, the wavelength is 1550,1310 nm)

2.

Multi-mode (2 km, the wavelength is 850,1300 nm)

Single mode is standard cable.

Conclusion:

In the end I would like to say that during my period in NESPAK Karachi Office as an internee I have

come across some wonderful professionals and by virtue of their commitment and dedication to

their work I have gained wonderful experience and knowledge of the corporate World and how it

functions. I would like to thank NEDUETs DIL (Directorate of Industrial Liasion) and NESPAK Karachi

Office for providing me with this glorious opportunity to be a part of this highly esteemed

organization.

Documents

NESPAK Internship Report