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Transcript of Start (ceb) new
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Acknowledgement
It is with great pleasure recollected the successful training period as a HNDE student at the
Ceylon Electricity Board. I gained valuable experiences & knowledge of practical
application in the field of electrical engineering. I take this opportunity to express gratitude
to;
Dr. D.L.A.H.Shammika (Past Director), Mr. Sunil Parana Vithanage (Assistant
Registrar), Mr. Bandula Ekanayake (Head of the Electrical Engineering
Department), and all the academic & non-academic staff members of the Advanced
Technological Institute, Labuduwa, Galle, for guiding & supporting to training for us.
Mrs. R.M.A.P.Samaradivakara (Assistant Director), Mr. S.Kodikara (Inspector-
NAITA), Mr. S.P.Kumara (Inspector-NAITA) and all the staff members of the
National Apprentice & Industrial Training Authority (NAITA) for organizing a
valuable & effective training for us.
Then big words of thanks and appreciate to the Ceylon Electricity Board,
Piliyandale for giving me this golden opportunity to complete my 3 months special
industrial training as a special apprentice.
I am specially pleased to convey my thanks to Mr. Hirantha Jayathilaka (Area
Engineer-Mawanella), Electrical Engineer-Projects & Heavy Maintenance Unit
(Central Zone) & the all the other officers & Staff on CEB.
I like to give my special regards to my father & mother giving me helping hand &
their blessing at this event & I express my utmost & sincere gratitude to each &
everyone who were concerned in providing apprentice training to the HNDE
diplomat.
G.R.S. Wasala Herath,
Department of Electrical Engineering,
Advanced Technological Institute,
Labuduwa,Galle.
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Preface
This report is based on the in-plant training of the second three months of Higher National
Diploma in Engineering – Advanced Technological Institute, Labuduwa, Galle. My training
place was Ceylon Electricity Board, Piliyandale.
They have the tasks of Generation, Transmission, Distribution and Maintenance of the
Electrical Energy in Sri Lanka. So I was able to visit many of their working places & take
part of their ongoing projects. When I was there I could be able to get vast knowledge.
Mainly about Transmission, Distribution, Maintenance & Utilization of Electrical Energy.
This report contained with my experiences and knowledge I gathered during my training
period from 13/05/2013 to 02/08/2013 (12 weeks).
This report contains three chapters. The organizational structure of the Ceylon Electricity
Board is described as the introduction in first chapter. Second chapter is included with my
experiences which are performed during my training period. And finally I was added the
suggestions I have made to maximize the efficiency of the organization and the conclusion
which includes a summary of the training period as the Third Chapter.
Finally the references, leave record form, training schedule, report certification, organization
certificate are added as annexes.
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Contents
CHAPTER 1
INTRODUCTION TO THE CEYLON ELECTRICITY BOARD
1.1 Introduction 09
1.1.1 Vision of the CEB 09
1.1.2 Mission of the CEB 09
1.1.3 The Board’s statutory obligation 09
1.2 Objectives of the CEB 10
1.3 Environmental policy of the CEB 11
1.4 The Strength of the CEB 11
1.5 The Weaknesses of the CEB 11
1.6 Organizational structure of the CEB 11
1.7 Administrative regions of the CEB 13
1.8 Profitability 15
1.9 Usefulness to the Society 15
1.10 EPF, ETF & Leaves 15
CHAPTER 2
TRAINING EXPERIENCE ON CEYLON ELECTRICITY BOARD
2.1 Lift branch-NHSL
2.1.1 Introduction 16
2.1.2 Main types of lifts 16
2.1.3 Main Components of a Lift 17
2.1.4 Typical arrangement of a Lift 21
2.2 Air Conditioning & Refrigeration Branch-NHSL
2.2.1 Introduction 22
2.2.2 Major components of the air conditioning system 22
2.2.3 Types of air conditioning system 25
2.3 Area office-Mawanella
2.3.1 Introduction 28
2.3.2 Organizational Structure of Area Office 28
2.3.3 Consumer Center 28
2.3.4 Procedure of new service connections 29
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2.3.5 Breakdown Services 30
2.3.6 Disconnections 30
2.3.7 Meter Testing 31
2.3.8 Billing & Revenue Function 31
2.3.9 Field tests 33
2.3.10 Single phase, Three phase KWh meter & kVA meter 34
2.4 Construction Branch-LSLCP Project (Katugastota)
2.4.1 Introduction 36
2.4.2 Service of provincial construction branch 36
2.4.3 Work sites of provincial construction branch 36
2.4.4 Overhead line construction 37
2.4.5 Main components of overhead lines 37
2.4.6 Line construction 43
2.4.7 Conductors & their materials 45
2.4.8 Construction materials & Tools 47
2.5 project & Heavy Maintenance Unit (Region -02)-Kandy
2.5.1 Introduction 48
2.5.2 Line inspection, maintenance & construction 48
2.5.3 Line stringing & jointing 49
2.5.4 Selection of towers 51
2.5.5 Primary substation 52
2.5.6 Parts of a primary substation 53
2.5.7 Hot line maintenance 58
2.6 Central Work Shop- Aniyakanda
2.6.1 Introduction 59
2.6.2 Insulation Materials 59
2.6.3 Electrical Motors 60
2.6.4 Motors Winding & Rewinding 60
2.6.5 The Casting Process 62
2.7 Power Plant-Kolonnawa
2.7.1 Introduction 63
2.7.2 Generator 63
2.7.3 Battery Maintenance 64
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2.8 Safety against Electricity 65
2.81 Common safety used in CEB 67
CHAPTER 3
CONCLUSION 69
REFERENCES 71
ANNEXES
Annex 1- Leaves record form 73
Annex 2- Training schedule 73
Annex 3- Training certification 74
Annex 4- Organization certificate 75
Annex 5- Report certification 76
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LIST OF FIGURES
Figure 01: Organizational Structure of the CEB 12
Figure 02: Administrative regions of the CEB 14
Figure 03: Side view of the Elevator & Data Plate of the Elevator Motor 17
Figure 04: Roping Methods of a Typical Elevator 18
Figure 05: Control Rooms of the 2 Elevators 18
Figure 06(a): Top view of the Elevator & Front view of a Dumpvator 19
Figure 06(b): Top view of a Governor 20
Figure 07: Typical Arrangement of a Lift 21
Figure 08: Typical view of Plate type (Left) & Finned type (Right) Condenser 23
Figure 09: Front view of a Evaporator 24
Figure 10: R-22 & R-404 A Refrigerants 25
Figure 11: Cross-section of a Window Type A/C 26
Figure 12: Cross-section of a Split Type A/C 26
Figure 13: Typical arrangement of a Chilled Water System 27
Figure 14: Cooling towers of a Chilled Water System 27
Figure 15: Organizational Structure of Area Office 28
Figure 16: Typical view of a single phase KWh meter 34
Figure 17: Connection layout of a kVA meter 35
Figure 18: Cross section & Typical view of a pin type insulator 39
Figure 19: suspension type insulator 40
Figure 20: strain type insulator 40
Figure 21: Towers 41
Figure 22: Wooden poles 41
Figure 23: R.C.C. Poles 42
Figure 24: Steel Poles 42
Figure 25: ACSR, AAC, Copper Conductors 46
Figure 26: Line stringing moment 50
Figure 27: Joint compression mid span-LT 50
Figure 28: Various kind of line supports 52
Figure 29: Outdoor Substation 53
Figure 30: Indoor Substation 53
Figure 31: Various types of bus bars arrangement in Indoor & Outdoor substation 54
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Figure 32(a): Surge Arrester 57
Figure 32(b): SF6 Circuit Breaker 57
Figure 32(c): Drop Down Lift Off 57
Figure 32(d): Oil Circuit Breaker 57
Figure 33: Side view of the winding finished fan 61
Figure 34(a): Two nozzles at the hearth 62
Figure 34(b): Special type of cove 62
Figure 35: Head & Face Protect Hard Hat 67
Figure 36: Hearing protector 67
Figure 37: Protective Gloves 68
Figure 38: Eye Protector 68
Figure 39: Safety Shoes & Boots 68
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LIST OF TABLES
Table 01: PUCSL approves the new electricity tariff (2013/04/20) 33
Table 02: Material used for LV, MV, HV lines & Substation 47
Table 03: Class of insulation Vs. Temperature 59
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CHAPTER 1
INTRODUCTION TO THE CEYLON ELECTRICITY BOARD
1.1 Introduction
The Ceylon Electricity Board (also abbreviated as CEB), is the largest electricity company in
Sri Lanka. With a market share of nearly 100%, it controls all major functions of electricity
generation, transmission, distribution and retailing in Sri Lanka. It is one of the only two on-
grid electricity companies in the country; the other being Lanka Electricity Company.
Opened in 1969, the company now has a total installed capacity of 2,684 MW, of which
approximately 1,290 MW is from thermal energy, and 1,207 MW is from hydroelectricity.
Due to low wind resource, rough terrain and poor road conditions in Sri Lanka, CEB owns
only one 3 MW wind farm in Hambantota, known as the Hambantota Wind Farm. The farm
consists of five turbines, measuring 600 KW each. CEB also manages numerous
hydroelectric dams such as the Victoria Dam, and power plants such as the Norocholai Coal
Power Station.
1.1.1 Vision of the CEB
“Enrich Life through Power”
1.1.2 Mission of the CEB
“To assist the PUCSL by ensuring to develop and maintain an Efficient, Coordinated and
Economical system of electricity supply to the entire population within the licensing area ,
while adhering to our core values; Quality, Service to the Nation, Efficiency and
Effectiveness, Commitment, Safety, Professionalism and Sustainability.”
1.1.3 The Board’s statutory obligation
The Board is under a statutory duty to develop and maintain an efficient, co-ordinate and
economical system of Electricity Supply. It is also the duty of the Board to generate or
acquire supplies of electricity; to construct, maintain and operate the necessary works for the
generation of electricity by all means, to construct, maintain and operate the necessary works
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for the inter-connection of Generating Stations and Sub-stations and for the transmission of
electricity in bulk from Generating Stations and Sub-stations to such places as may be
necessary from time to time; to distribute and sell electricity in bulk or otherwise.
It is the duty of the Board to exercise its powers and perform its functions so as to secure that
the revenue of the Board are sufficient to meet its total outgoing properly chargeable to
revenue account including depreciation and interest on capital, and to meet a reasonable
proportion of the cost of the development of the services of Board.
1.2Objectives of the CEB
CEB has a set of “Strategic Themes” or “Strategies” (also referred to as “Long term
objectives”) formulated in order to realize the organizations long term Vision and Mission.
They are as follows.
Provide Electricity to all at all times within the licensing area.
Improve the quality of supply and service to customers.
Transform Ceylon Electricity Board to become a financially viable entity.
Improve CEB’s standing as a responsible Corporate Citizen;
Develop Clean Energy to the optimum level.
CEB to have a proud and competent workforce.
In order to achieve the Corporate Vision, Mission and Strategies, Ceylon Electricity Board in
2010 has adopted the Balanced Score Card (BSC), a world renowned Strategy Management
Tool. The Corporate Strategy Division of the CEB has undertaken the task of implementing
BSC within the CEB and by July 2012 has already formulated a Corporate Balanced Score
Card to monitor CEB’s performance through a set of Key Performance Indicators (KPI).
With the full implementation of the Balanced Score Card system within the CEB, the
organization will be able to better communicate its Strategies to all employees, align all its
processes towards achieving its strategies and monitor the progress in achieving the
organizational Strategies.
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1.3Environmental policy of the CEB
CEB will manage all its business activities in a manner, which cares for the natural and
manmade environment and contribute to sustainable development. By means of openness in
dealing with environmental issues, we intend to create confidence in our activities on the part
of the public, customers, authorities, employees, and owners. We will actively pursue a
policy of incorporating and integrating environmental considerations into our activities.
1.4The Strength of the CEB
CEB is currently the only power producer in Sri Lanka. And it owns assets of about Rs 300
billion. On the other hand CEB is the only place where an electrical engineer can make use of
his knowledge in maximum efficiency. Especially the opportunities they get to work at the
major hydro power plants are found in no other place of Sri Lanka except the CEB. It also
employs engineers from top to bottom of its hierarchy. And most of the top level Decision
making is done though a well experienced professional staff.
1.5 The Weaknesses of the CEB
CEB is an organization which is operated under the Sri Lanka Government. So the rights of
the employees are significantly strong. So the employees, who are not taking a part of the
critical decision makings and the critical issues, are acted in an unproductive manner. This
makes CEB a loss counting organization. And also, because of CEB is operated under the
government, some important decisions like building plants are taken through the government.
So the control of the CEB is gone out of its hand, sometimes to the people who are not having
the proper understanding of the field’s important areas. This makes the operation difficult to
CEB.
1.6 Organizational structure of the CEB
In the CEB organizational structure the general manager is the chief executive office. Only an
electrical can be promoted to this position. The corporate management of the of the CEB
consists of General Manager and seven special class officers from the electrical engineering
service and one finance manager for special class officer of accounting service. All corporate
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management members designate additional General Managers (AGM’s) except the finance
manager. The organization structure is shown in figure 01.
Figure 01: Organizational Structure of the CEB
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1.7Administrative regions of the CEB
Region 01- Colombo city
Northern Province
North Central Province
North western province
Region 2- North Central Province (Polonnaruwa district)
Eastern Province
Central Province (Kandy District)
Region 3- Uva Province
Sabaragamuwa Province
Central province
Region 4- Southern Province
Western Province South -01
~ 14 ~Figure 02: Administrative regions of the CEB
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1.8 Profitability
As said above, the CEB is conducted under huge losses. This had made the organization
unprofitable. Proposals to improve the profitability had come out time to time. But due to
some reasons, these attempts have been restrained.
1.9 Usefulness to the Society
The electricity, as said above, is an essential service. Manipulating such a sector in are liable
manner is a great social service to the country. Even though the distribution ends are having
come problems, as a macro scale picture, CEB provides a quality vice very good service
through the generation, transmission and satisfactory service through distribution. The staff in
key positions of the institute are always try to conduct a safe and reliable service to the
country. As an example, the number of blackouts is minimum and the voltages in the
transmission ends are usually kept within the range.
1.10 EPF, ETF & Leaves
To all the employees granted the EPF & ETF as employee and Board contribution 10% and
15%.
EPF (Employee Trust Fund)
10% Employee
15% Company
ETF (Employee Trust Fund)
3% Company
Leaves
CEB employee can get leaves as follows:
Annual Leaves 14 Days (Working Days)
Medical Leaves 21 Days
Casual Leaves 07 Days
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CHAPTER 2TRAINING EXPERIENCE ON THE CEYLON ELECTRICITY BOARD
2.1 Lift Branch
2.1.1 Introduction
Lift or elevator is a device which it’s used for vertical transport of passengers or freight to
different floors or levels, as in a building or a mine. Elevators consist of a platform or car
traveling in vertical guides in a shaft or hoist way.
During my training period I was able to train in the General Hospital lift branch. The depot
includes an electrical superintendent and a gang of technicians. They provide 24-hour
breakdown service in the hospital.
Designs of lift equipments are strictly related to the long standing, progressively updated,
which referred to two vital matters.
(a) Safety in operation.
(b) Recommended dimension related to load and speed, and based on the conditions
for safe operation.
Normally the lifts are operated by electric power, where AC motors and sometimes DC
motors are used to move the elevator. By controlling the speed of the motor the speed of the
elevator can be changed. The direction the movement of the car can be changed by changing
the current direction of the DC motor in the case of a DC motor or by inter changing the two
phases in the case of an AC motors.
2.1.2 Main types of lifts
Lifts can be categories in the view of applications used in different places.
- Passenger lifts
- Hospital or Bed lifts
- Freight lifts
- Good lifts (Dumbwaiters)
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2.1.3 Main Components of a Lift
All machine room we saw was in top most floor of a building. But the machine room can be
situated in the bottom of the building also. Inside it there are electric motor, control panel,
over-speed governor, etc. Control panel consists of relays, indicators, MCB and etc.
Motor:
Main motor is AC induction motor and other motors are DC motors used for the lift.
Normally, the motor use for lift is a three-phase induction motor. This motor is use to travel
the Lift car one floor level to another floor level. Direction of rotation of the motor is change
by changing two current phases. It is automatically changed inside the control panel. Motor
operates at two deferent speeds. Because car is moving faster speed as soon as start to move
and getting slowdown before stop as the floor level.
Ropes:
All electrical connection to the car is made by means of the multi core hanging flexible cable.
One end of which is connected to a terminal box fitted under the car floor. The other end to a
terminal box fitted in at approximately the mid- position. This is used to hold lift car.
Breaking strength of the rope should be 10 to 12 times the capacity of the car. There are two
roping methods.
Figure 03: Side view of the Elevator & Data Plate of the Elevator Motor
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1. One to One
In this case, the ends of the elevator ropes are connected on the car and the counter
weight as shown in figure.
2. Two to One
In this type, the both ends of the ropes are tied on suitable places of the control
room.
Control System:
Control unit consists of relays, operating switches, contactors, rectifiers, resisters and
capacitors. It receives signals from the selector and the lift. Then it controls lift according to
these signals. In early days, electro-mechanical relay panels are used as controllers. Now,
microprocessor based controllers are used.
Figure 04: Roping Methods of a Typical Elevator
Figure 05: Control Rooms of the 2 Elevators
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Counter Weight:
The object of the counter weight is to provide traction and to balance the weight of the car
plus a predetermined proposition, usually 40 to 50 percent of the maximum car load and
thereby to reduce the size of the motor. Incidentally the counter weight provider a certain
measure of safety when landing on its buffer and removing traction from the car. This can be
identifying as main part of the lift. Controller is received signal from endings. Lift car, Lift
motor etc. The signals are used to activate the lift to various positions.
Brake System:
Break unit should be capable of handling 125% of load. Normally break is kept applied.
When the lift works, solenoid will activate and it pulls back brake pads. After that, break
releases and lift starts to function. When the lift is stopped due to a power-cut or any other
failure, break is released using a handle manually.
Lift Car:
This is the container like structure that used to carry something in it belong to the requirement
of it is designed. There are floor level indicators, over weight alarm, telephone to use in the
case of emergency, switches to send the position we want to stop the lift.
Figure 06(a): Top view of the Elevator & Front view of a Dumpvator
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Guiders:
Some form of guiding is necessary for both the car & counter weight so that they will travel
in a uniformly vertical direction. The guides must be of such length that it will be impossible
for any of the car or counter weight shoes run of the guides. In the most common
arrangement two guides are required for the car & for the counter weight.
Over Speed Governor:
This is a safety device. Governor is adjusted so that,
If speed is 115% of normal speed, electrical trip occurs due to the breaking fails or
control panel fails.
If speed is 130% of normal speed, mechanical trip occurs due to rope breakdown.
When rope breaks, if load is applied to the rope attached to over speed governor then rope
operates by the safety gear. When the car speed exceeds more than 20 % of the maximum
speed of the car and power supply did not cut off or by cutting off the power supply does not
stop the car then Over Speed Governor operates. Over Speed Governor operates the safety
gears located at the bottom of the car. Safety gear is a mechanical lock that car can be stop by
locking it to the car guide.
Travelling Cables:
Control signals and communicating signals are passed through this flexible electrical cable. It
consists of number of wires inside it. One end of this flexible cable has connected to the
control panel and the other end has connected to the bottom of the car.
Figure 06(b): Top view of a Governor
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2.1.4 Typical arrangement of a Lift
Figure 07: Typical Arrangement of a Lift
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2.2 Air Conditioning & Refrigeration Branch
2.2.1 Introduction
In my training I was able to train in Air conditioning branch of the Ceylon Electricity Board,
located at the General Hospital carries out repairs and maintenances of all the air conditioners
installed in the general hospital.
Refrigeration is defined as the process of removing heat from an enclosed space or from a
substance, and rejecting it elsewhere, for the primary purpose of lowering the temperature of
the enclosed space or substance and then maintaining that lower temperature.
Air conditioning takes various forms depending upon the requirements, but essentially it is a
system of delivering cooled air to a given space and maintaining the area at a given
temperature, and sometimes humidity.
2.2.2 Major components of the air conditioning system
Compressor:
A air conditioning or heat pump compressor which compresses low pressure refrigerant gas
into a high pressure, high temperature gas. Usually the compressor is in the outdoor portion
of an air conditioning or heat pump system. The compressor is basically a high pressure
pump driven by an electric motor. The air conditioning compressor is usually packaged in the
outdoor compressor/condenser unit. Compressors used in the air conditioners can be
categorized in to four types according to the way they compress the vapor.
Reciprocating compressors
Screw compressors
Centrifugal compressors
Rotary compressors
Stationary Blade type.
Rotating blade type.
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Condenser:
A condenser or condensing unit: typically a condensing coil inside which high temperature
high pressure refrigerant gas flows, and over which a fan blows air to cool the refrigerant gas
back to a liquid state (thus transferring heat from the refrigerant gas to the air being blown by
the fan).
The condenser unit is basically a coil of finned tubing and a fan to blow air across the coil.
Usually the condenser unit is in the outdoor portion of an air conditioning system, often
packaged along with the compressor motor. The change of state of the refrigerant, from hot
high pressure gas to a liquid releases heat, including heat collected inside the building to the
outdoors.
Condensers are divided into two groups according to the construction.
Plate type
As shown in below figures there are several types of plate condenser. One type has
wire mesh connected to the Cu (or M.S.) tube. This type of condensers is used in
refrigerators. Another type has a M.S. plate connected to the tube.
Finned type
In this type of condenser there is large number of thin Al sheets inserted between Cu
tubes. There for it has a higher surface area for cooling. Therefore it has a higher
efficiency. This type of condensers is used in window type and small split type air
conditioners.
Figure 08: Typical view of Plate type (Left) & Finned type (Right) Condenser
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Expansion Valve:
Expansion valve performs two tasks. One is that it converts high pressure low temperature
liquid into mixture of low pressure low temperature liquid and vapor. Other task is that it
controls the flow of refrigerant to the evaporator. Because of this it is also known as throttling
valve and refrigerant flow control.
Types of expansion valve there are many types of expansion valve. Few of them are
explained below.
Capillary Tube
This is the simplest form of the expansion valve. It is a long tube very small diameter.
Because of this shows high resistance to the flow of refrigerant result is low pressure
appear in the evaporator side. This is used in window type air conditioners.
Automatic expansion valve
Automatic expansion valve maintains a constant pressure in the evaporator. But it
does not control the flow of refrigerant to the evaporator.
Thermostatic expansion valve
In this type of valves, flow of refrigerant to the evaporator is controlled according to
the heat of the suction line.
An evaporator coil or cooling coil:
An evaporator coil or cooling coil: typically the cooling coil is a section of finned tubing (it
looks a lot like a car radiator) into which liquid refrigerant is metered and permitted to
evaporate from liquid to gas state inside the coil. This state change of the refrigerant, from
liquid to gas, absorbs heat, cooling the evaporator coil surface and thus cooling indoor air
blown across the cooling coil. Usually the cooling coil is located inside the air handler.
Figure 09: Front view of a Evaporator
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Refrigerant:
A refrigerant is a compound used in a heat cycle that under goes a phase change from a gas to
a liquid & back. The two main uses of refrigerants are refrigerators/freezers & air
conditioners. Normally R-22 was used for A/C systems. (R-22 is a single HCFC compound)
R-404/R-404 A is used specially for mortuaries. Because it has more favorable
thermodynamics properties.R-12 is not used in now because of the “green house effect”.
2.2.3 Types of air conditioning system
Air conditioners can be categorized in to three groups according to the way they are
manufactured.
1) Window type
2) Split type
3) Chilled water system
Window Type:
That cool gas vapor will go to the compressor and come as high gas vapor through the
discharge tube.
Figure 10: R-22 & R-404 A Refrigerants
~ 26 ~
Split Type:
This type is available in small size and medium size. Here the system comes as two units;
condensing unit and air handler. Condensing unit consists of compressor, condenser coil and
fan.
.
Figure 11: Cross-section of a Window Type A/C
Figure 12: Cross-section of a Split Type A/C
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Chilled Water System:
Chilled water system is used in large buildings. In that type of buildings it is uneconomical to
use split type A.C. plants. Using gas refrigerant as cooler is not also suitable because the
length of the line needed is great. In chilled water system refrigerant is used to cool the water.
And that water is then sent to the air handler through heat insulated Cu tubes. To cool the
compressed refrigerant a water cooled condenser is used. And that water is then sent to a
cooling tower to be cooled by the air. From there it is sent back to condenser.
Figure 13: Typical arrangement of a Chilled Water System
Figure 14: Cooling towers of a Chilled Water System
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2.3 Area Office
2.3.1 Introduction
Area Engineer Office has a main role, when providing services of CEB to their consumers.
There are relevant Electrical Superintendents for the different sections and Assistant
Engineer, under the Area Engineer. The different sections of the Area Engineer Office are
Commercial, Planning, Billing, New supplies, Consumer Centers estate approval of the Area
Engineer is necessary for every new supply of relevant area. As well as every Breakdown
services, disconnecting supplies, checking of given consumer meters, Estimating for new
supplies, Examine of illegal supplies are done by the Area Engineer Office.
During my training period I was able to train in Mawanella Area Office. It carries out three
branches official, commercial & maintenance works. In here area office & other branches
were administrated by Area Electrical Engineer, Engineer Assistant & Electrical
Superintendants. Mawanella, Dippitiya, Hemmathagama are main depot of this area.
2.3.2 Organizational Structure of Area office
2.3.3 Consumer Center
CEB has established consumer service centers CSC (earlier called Depots), to carryout
various functions at distribution level. According to the organization structure of CEB, A
Eng.
AssistantChiefCleark
Clerical Staff
Figure 15: Organizational Structure of Area Office
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2.3 Area Office
2.3.1 Introduction
Area Engineer Office has a main role, when providing services of CEB to their consumers.
There are relevant Electrical Superintendents for the different sections and Assistant
Engineer, under the Area Engineer. The different sections of the Area Engineer Office are
Commercial, Planning, Billing, New supplies, Consumer Centers estate approval of the Area
Engineer is necessary for every new supply of relevant area. As well as every Breakdown
services, disconnecting supplies, checking of given consumer meters, Estimating for new
supplies, Examine of illegal supplies are done by the Area Engineer Office.
During my training period I was able to train in Mawanella Area Office. It carries out three
branches official, commercial & maintenance works. In here area office & other branches
were administrated by Area Electrical Engineer, Engineer Assistant & Electrical
Superintendants. Mawanella, Dippitiya, Hemmathagama are main depot of this area.
2.3.2 Organizational Structure of Area office
2.3.3 Consumer Center
CEB has established consumer service centers CSC (earlier called Depots), to carryout
various functions at distribution level. According to the organization structure of CEB, A
AreaEngineer
Clerical Staff
ES (Office)ES
(Commercial)
ES (AMU)
Figure 15: Organizational Structure of Area Office
~ 28 ~
2.3 Area Office
2.3.1 Introduction
Area Engineer Office has a main role, when providing services of CEB to their consumers.
There are relevant Electrical Superintendents for the different sections and Assistant
Engineer, under the Area Engineer. The different sections of the Area Engineer Office are
Commercial, Planning, Billing, New supplies, Consumer Centers estate approval of the Area
Engineer is necessary for every new supply of relevant area. As well as every Breakdown
services, disconnecting supplies, checking of given consumer meters, Estimating for new
supplies, Examine of illegal supplies are done by the Area Engineer Office.
During my training period I was able to train in Mawanella Area Office. It carries out three
branches official, commercial & maintenance works. In here area office & other branches
were administrated by Area Electrical Engineer, Engineer Assistant & Electrical
Superintendants. Mawanella, Dippitiya, Hemmathagama are main depot of this area.
2.3.2 Organizational Structure of Area office
2.3.3 Consumer Center
CEB has established consumer service centers CSC (earlier called Depots), to carryout
various functions at distribution level. According to the organization structure of CEB, A
ES (AMU)ES
(Depot)Area Store
Keeper
Figure 15: Organizational Structure of Area Office
~ 29 ~
CSC belongs to an area office. Usually one area office responsible to the three consumer
centers. In one CSC have one Electrical superintendant and few office staff and technicians. I
was at Mawanella CSC, in my training in CSC, I got the opportunity to attend;
Distribution line Repairs and New service line estimates
Giving supplies[Normal/Bulk]
Get consumers’ claims about the supplies
Breakdown services
Paying Bills[Available in some Consumer Centers]
2.3.4 Procedure of new service connections
First we have to get the application from the CSC (Customer Service Centre) and Fill
it and must certify by the Gramasewaka and the Sectional Secretary.
If the customer is not the owner of the home/land he should take the letter from the
owner that regarding he has no objections to the new supply.
That completed application must hand over to the CSC.(Should be submitted neighbor
electricity bill, ID copy, Plan of the land)
Then the responsible of CSC will visit the customer’s home and make an estimate.
Then the customer has to pay the estimated amount in PIV (Pay In Voucher).
Then the customer has to make an agreement with the CEB.
After complete the all above steps customer will get the electric supply within 14
days.
If supply line lay through other lands also
The consumer should get the agreement of that land owners with letters.
If anyone disagrees, the CEB sends D-Notices to them through the Area Engineer
according to the Electricity Act at 1985.
Then ES and Divisional Secretary of relevant area go to the place and discuss with
relevant sectors and decide the most suitable way for lay the supply line.[If anyone
disagree they can get legal actions]
After giving new connection Meter No, Current meter reading, Seal No, Supply Date
should be noted.
~ 30 ~
2.3.5 Breakdown Services
The Breakdowns of overhead lines may be happened at anytime by natural reasons, human
effects or without both of them. So there should be a good, efficient Breakdown Service to
CEB for give a better service for consumers. Because electricity is a main human need at
industrial and domestic purposes. The Breakdowns of Low Voltage lines are mainly done
through the Consumer Service Centers. There are special gangs to do High Tension line
services of whole over the island, called as Hotline Service.
The services of LV lines are mainly done according to consumers’ claims. In this process the
priority is given in danger of the breakdown. If someone is caused to the damage of the
overhead line, the relevant person has to pay for that loss to the CEB. The loss is estimated by
the CEB. The common break down is burning HRC Fuse in distribution line due to natural
reasons (like falling tree) or other reasons.
Direct contact of phase to phase
Direct contact of phase to neutral
Direct earthling of a phase
Loose connection of tapping points of distribution line and service cable
Breaking of service cable.
Breakdowns of consumers’ suppliesIf there is a breakdown on the supply of a consumer, first he should give a complain to the
Consumer Service Center of relevant area. If there isn’t caused consumer’s fault to that
breakdown, the CEB will be given the service by free of charge.
2.3.6 Disconnections
Consumers are responsible to pay their bills within the given one month period. If they do not
pay their bills The CEB officers have to get those arrears anyhow. It is not easy to apply
pressure on each consumer. So they Disconnect supply to the consumer. From that the
particular consumer and others encourage to pay their bills on time.
First the relevant area office will send a red notice to the consumer. After about two weeks,
Relevant Es & a technician visit consumer residence and ask the consumer to represent
~ 31 ~
payments made after receiving the red notice. If that person unable to represent that
payments, disconnection is done. As well as,
1) Taking electricity by illegal ways.
Most of the times some consumers are damaged to consumer meters. According to the
CEB standards the maximum error of a consumer meter should be + or - 2.5%. The
Service Meter is a property of CEB. So a consumer who cause to a damage of a
consumer Meter, has to pay for it. The CEB can be taken legal actions against them.
There is a section under the Area Engineer to Meter Checking for illegal supplies.
2) Also Natural Disasters are caused to disconnecting supplies.
Ex. Floods, Storms, Earthquakes etc.
2.3.7 Meter Testing
Consumer meter testing process is done by an area office. When a consumer requests to
check the KWH meter after completing relevant application, there we fix a text meter with
parallel to original meter.
Accuracy rate = Different of fix meter value - Different of test meter value
Different of text meter values
If the answer is more than + or - 2.5 we replace the meter. Else we keep the original meter as
it is.
2.3.8 Billing & Revenue Function
This is most important, complex & large function which handled through the area office. All
the power generation & other cost (fuel cost, depreciation cost, taxes & insurances,
maintenance cost, salaries……..etc) are covered by through this income, earn through the
electricity bill.
The rate at which electrical energy supply to consumer is known as a tariff. It depends nature
of the consumer. There are seven types of customers in the CEB(Since 2013/04/20),
1) Domestic 5.) Hotel
2) General 6.) Government
3) Industry 7.) Street Lighting
4) Religious
~ 32 ~
All the electricity consumers belong to one of the above segment. To complete this process,
meter reader act very important role. They go to read the meter within a day cycle. They can
keep minimum 20 days & maximum 45 days between two bills.
The tariff book is very important to them in this process. It’s a book which includes all the
value for 1-1200 units for different day cycle (20-45). Thorough this process always
consumer get average value of bill.
Electricity bill is very important document. We can get very important facts from a bill about
consumer & it process. We can see some important code number mention on the bill.
1) Account number
This is specific number for consumer. The consumer’s all details mention under this
number.
2) Work order number
Ex: 32-10-001
32 = Meter reader number
10 = Group number
001 = Consumer house number
~ 33 ~
2.3.9 Field tests
Field tests are done when there is a considerable change in the present meter reading with the
previously taken readings due to an error of the meter. And also it may sometimes be helpful
to identify illegal tapping of electricity.
Special portable equipment’s are available to find errors involved in the meters. Some of
these errors may adjust at the field and the meters will be subjected to test in order to make
sure whether they give the correct reading, otherwise the meters have to be brought back to
the meter testing lab for adjustments and re-calibration.
Table 01: PUCSL approves the new electricity tariff (2013/04/20)
~ 34 ~
2.3.10 Single Phase, Three phase KWh meter & KVA meter
Single Phase KWh meter:
To measure the load, the line voltage and the consumer load current must be introduced into
the meter. The current phase displacement (cos Φ) must also be measured, in order to
produce a driving torque, which is proportional to the active load.
The current is measured by driving it through a coil (the current coil) in the meter current coil
is in series with the consumer load, always in the phase wire. To measure the voltage a
second coil (the voltage coil) in the meter is connected to the line voltage between the phase
wire and the neutral wire. The ends of the both coils are connected to the terminal block
inside the meter.
The cable from the power company and the consumer wiring are connected to the outside of
the terminal box. The phase wire current enters and leaves the meter via the two terminals [1
and 4]. Two terminals [2 and 3] serve to connect the neutral wire and the voltage coil. The
other end of the voltage coil is connected internally to the current input terminal [4], which
carries phase potential.
Figure 16: Typical view of a single phase KWh meter
~ 35 ~
Three Phase KWh meter:
All the three phase energy meters have the same construction as in the single-phase meters.
The different of this type is it contains a set of voltage and current coil for each phase. All
three sets are therefore drive the disc and a single magnet are for the breaking torque.
Some meters contain two discs instead of one. Their current fluxes are in phase with the line
currents and the voltage fluxes lag the line voltage by right angle. Most of three phase meters
are programmable poly-phase meter, which can be used to measure lot of parameters such as
active energy, reactive energy, KVA demand and current, voltage and power factor of each
phase.
The adjustments are similar to single-phase kWh meters. There are two types of 3 phase kWh
meters. Those are “with CT” and “without CT” (direct supply)
kVA meter:
The kVA meters are used to measure apparent energy consumed. CEB charges for maximum
demand (kVA units) for bulk supplies. kVA demand meters are used to measure maximum
demand. In the meter the voltage coils are delta connected.
Figure 17: Connection layout of a kVA meter
~ 36 ~
2.4 Construction Branch
2.4.1 Introduction
Provincial Construction Branch is a main section of CEB Provincial Office. It is governed by
a Chief Engineer under the Deputy General Manager of Provincial Branch. High capacity
Electricity Supply projects are done through the Provincial Construction Branch. For this
purpose there are many Electrical Engineers, Civil Engineers, Electrical Superintendents
under the Chief Engineer for different sections, like;
Planning.
Estimating.
Constructions.
In my training period I was assigned to the LSLCP Project (Lighting Sri Lanka Central
Province).In here five members of engineers are working there. Likewise clerical staff also
works for the documentary works of the project. In here we familiarized with identification of
construction materials, equipments & tools. Likewise I was able to gather knowledge about
the line pegging & estimation.
2.4.2 Service of provincial construction branch
There are special gangs under the Site Engineers and Electrical Superintendents for the
construction sites. For,
Planning for new electricity projects.
Survey for new projects and estimating.
Erecting of poles and Laying supply lines for new electricity supply projects.
Erecting of Transformers for Bulk Supplies and other projects.
The CEB gets also the public contractors service for the projects of the Provincial
Construction Branch.
2.4.3 Work sites of provincial construction branch
The Provincial Construction Branch has established their work sites to continue the electricity
projects of CEB. There is a Site Engineer as the head of the site. These sites have special
gangs which are governed by Electrical Superintendents for do the construction projects.
~ 37 ~
These gangs have to cover the every area of the relevant Province. As well as the ES who is
the head of the gang examines the projects which are done by the public contractors. All of
these sites have time durations to finish the projects. The relevant Electrical Superintendents
have to make estimates to their projects. After finished the project, it handover to the relevant
Area Engineer of that area through the Provincial Branch.
2.4.4 Overhead line construction
Electric power can be transmitted or distributed either by means of underground cables or by
overhead lines. The underground cables are rarely used for power transmission due to two
main reasons.
Firstly, power is generally transmitted over long distances to load centers. Obviously, the
installation cost s for underground transmission will be very heavy.
Secondly, electric power has to be transmitted at high voltages for economic reasons. It is
very difficult to provide proper insulation to the cables to withstand such higher pressures.
Therefore as a rule, power transmission over long distances is carried out by using overhead
lines. With the growth in power demand and consequent rise in voltage levels, power
transmission by overhead lines has assumed considerable importance. An overhead line is
subjected to uncertain weather conditions and other external interferences. This calls for the
use of proper mechanical factors of safety in order to ensure the continuity of operation in the
line. .
2.4.5 Main components of overhead lines
An overhead line maybe used to transmit or distribute electric power. The successful
operation of an overhead line depends to a great extent upon the mechanical design of the
line. While constructing an overhead line, it should be ensured that mechanical strength of the
line is such so as to provide against most probable weather conditions.
Insulators:
In order to prevent the flow of current to the earth from support the transmission lines or
distribution lines are all secured to the supporting towers or poles with the help of insulators.
~ 38 ~
The insulators of a transmission line are its most important item, since the operation of a line
cannot be any better than the insulators that support the conductors. Transmission line
insulators must possess good mechanical strength and good insulating qualities under all
conditions of weather and temperature and must not deteriorate fast. Insulators are made of
glass, porcelain and patented compound, glass is cheapest material and when properly made
will produce satisfactory insulators for low-voltage work, such as telephone and telegraph,
and under favorable conditions may be used up to 25kv.though there are a number of
patented compounds on the market these seem to offer much competition with porcelain,
since porcelain has very good electrical characteristics as well as high mechanical strength.
Properties of insulators-
Insulator must posse following qualities;
High mechanical strength
High insulation resistance
Ability of with stands high temperature variations.
Types of insulators used in medium voltage line:
1) Pin type insulators
2) suspension type insulators
3) Strain type insulators
1) Pin type insulators
The part section of a pin type insulator is shown in figure 18. As the name suggests the pin
type is secured to the cross arm on the pole. There is a groove on the upper end of the
insulator for housing the conductor. The conductor passes through this groove and is bound
by the annealed wire of the same material. Pin type insulators are used for transmission and
distribution of electric power at voltages up to 33KV.Beyond operating voltage of 33KV, the
pin type insulators become too bulky, and hence uneconomical.
2) suspension type insulators
The cost of pin type insulator increases rapidly as the working voltage is increased.
Therefore, this type of insulator is not economical beyond 33KV. For high voltage (>33KV),
it is a usual practice to use suspension type insulators shown in figure 19.
~ 39 ~
They consist of a number of porcelain discs connected in series by metal link in the form of a
string. The conductor is suspended at the bottom end of this string while the other end of the
string is secured to the cross arm of the tower. Each unit or disc is designed for low voltage;
say 11KV .The number of discs in series would obviously depend upon the working voltage
.For instance, if the working voltage is 66KV, than six discs in series will be provided on the
string.
3) Strain type insulators
When there is a dead end of the line or there is corner or sharp curve, the line is subjected to
greater tension .In order to relive the line of excessive tension, strain insulators are used for
low voltage lines (<11KV), shackle insulators are used as strain insulators. However, for high
voltages transmission lines, strain insulators shown in fig 20. The discs of strain insulators are
used in the vertical plane. When the tension in the lines is exceedingly high, as at long river
spans, two or more strings are used in parallel.
Figure 18: Cross section & Typical view of a pin type insulator
~ 40 ~
Line Supports:
The supporting structure s for overhead line conductors are various types of poles and towers
called “line supports”. In general the line supports should have the following properties.
High mechanical strength to withstand the weight of conductors and wind loads etc.
Light in weight without the loss of mechanical strength
Cheap in cost and economical to maintain
Long life
Easy accessibility of conductors for maintenance
The line supports used for transmission and distribution of electric power are of various types
including wooden poles, RCC poles, steel poles and lattice steel towers .The choice of
supporting structure for a particular case depends upon the line span, cross sectional area, line
voltage, cost and local conditions.
Figure 19: suspension type insulator Figure 20: strain type insulator
~ 41 ~
Towers:
For every great heights and extra high voltage, transmission towers are used (as shown in
figure 21) various angle iron sections are used to form a close cage to form tower.
Wooden poles:
These are light in weight and cheap in comparison with all other types of poles, made up of
modern beam. These are easily affected and spoiled by atmosphere, rain water, white ant soil,
moisture, etc. These are used for temporary works and with special chemical coating for
works of permanent nature.
Figure 21:Towers
Figure 22:Wooden
poles
~ 42 ~
R.C.C Poles:
These are made by reinforcing steel rods in concrete slabs of pole shape .The usual ratio of
mixture is 1:1:5:3 for cement, sand, stone rubbles and steel rods respectively. These poles are
of permanent nature, long life, unaffected by rain sunlight etc. So are usually used nowadays.
Ducts are provided inside the poles section along its length for,
Drawing cables/wires
To keep its weight less
Steel poles:
Steel poles are of L shape, rail type and tubular in shape. These poles are heavy in weight and
cheaper than R.C.C poles. Atmospheric moisture, rain etc., affect these poles hence while
using, these poles are always painted or coated with chemicals to avoid rusting.
Figure 23:R.C.C.Poles
Figure 24:SteelPoles
~ 43 ~
Vibration dampers
Vibration dampers are used in the line near the towers. This is used to control the swing of
the line caused by the wind.
Suspension and tension clamps
These clamps are used to hold the power line with the insulator set.
End joints
End joints are used at terminal points of the power line. Some times in tower lines they are
used at points where line changes the direction.
2.4.6 Line construction
Selection of route:
Following factors should be considered when selecting a line route.
One side of the road is used as far as possible.
Amount of way leave to be cleared shall be minimized.
Inconvenience caused to the other services shall be minimized.
Swampy ground and areas liable to flood shall be avoided.
Routes which would involve excavation in rock shall be avoided
The use of taller poles at uplifts shall be avoided and construction of tension points at
uplifts also be avoided.
As far as possible route shall be least expensive to board.
Selection of poles:
All poles used in the LV lines should be concrete poles. However wooden poles may be used
in difficult terrain with the recommendation of the chief engineer (construction) of the
province. 8.3 m 100 kg RC poles shall be used for LV lines. However 9m 115 kg poles may
be used to maintain the ground clearances where necessary. 8.3 m 100 kg pre stressed poles
also may use in difficult terrain. Erection of self-supported 8.3 m 500 kg RC pole may be
recommended where erection of stays and struts is not possible due to ground conditions.
~ 44 ~
Handling and transportation of concrete pole:
Concrete poles for electrical distribution networks are designed to have a strength in the
down line direction at least ¼ the strength in the transverse direction. The shape of a section
through a typical concrete pole easily demonstrates this difference in strength. Therefore a
pole must be stored, transported, and handled at all times with its longer axis in the vertical
plane to ensure that the resulting forces are always resisted by the poles stronger direction.
Poles must not be dropped off a truck but lifted by means of crane. Poles should not be jarred
by twisting the cross arm. During erection the pole should not be allowed to bend on the flat
or wide sides, or to lurch against the side of the hole when it is dropped into place. The poles
should be transported on a suitable vehicle supported full length or with a limited amount of
overhang. The poles should be lifted by crane from the transporter and placed on the ground.
They must not be dropped.
Installation of stays and struts:
Stay arrangement
When a line changes direction, an additional force is introduced at the angle pole. This force
is the resultant of line tensions acting at the pole .The resultant force tries to move the top of
the pole in the direction that bisect the angle between the wires. These forces, due to angles,
can be considerable. The stays, struts and flying stays shall be fixed to neutralize the resultant
force on the poles. Number of stays to be used at any particular pole location is designed on
the overturning force acting on the pole.
String of Conductors
During running out, the cable drum should be securely supported on drum jacks, with and the
axle should be level. The work areas should have sufficient employees on site to ensure that
the conductors are not damaged by contact with the ground or pole equipment during running
out. Care should be taken to avoid kinking, twisting or abrading the conductor in any manner.
Conductor should not be trampled on, run over by vehicles or dragged over the ground.
Vehicles should not be used to run out conductors. Special care must be taken when running
out conductors near other existing electrical systems, whether they are alive or not.
~ 45 ~
Tensioning and binding (bare conductors):
All Aluminium 7/3.40 mm (fly) and all Aluminium 7/4.39mm (wasp) conductors shall be
used for LV line. Earth wire no: 8 shall be strung on the top of the pole before stringing the
bare conductors. Conductors shall be strung in vertical formation as per drawings. After final
tension of the conductor LV shackle insulator shall be fixed to the D brackets of the
intermediate poles.
Conductors shall be bound to the insulator at each support using Aluminium-binding wire no:
11. Only one mid span joint per conductor shall be allowed for a shackle point span .All mid
span joints shall be compression type. During stringing of conductors maximum precautions
shall be taken to prevent excessive strain and damage to the conductor. Standard sag and
tensions applicable to the particular size of conductor shall be maintained. The conductors
shall be tensioned using ratchet pullers and wire grips (come along clamps) designed to
prevent damage to the conductor using tensioning.
2.4.7 Conductors & their materials
The purposes of the conductors are to carry the load current from the generating station to the
substations and from substations to the consumer’s premises. So conductors are made of that
material which has;
High conductivity
High tensile strength
If is easily available
Cheap Following conductors are used for overhead line:
Copper
Aluminium
ACSR (Aluminium Conductor Steel Reinforced)
AAC (All Aluminium Conductor)
Copper:
From the point of view of conduct and tensile strength copper conductor is used, but being
very costly and requiring to be imported, nowadays, it is not used as conductor material for
overhead lines in our country. (Shown in figure 25(c))
~ 46 ~
ACSR:
These conductors are made up of galvanized steel surrounded by stranded Aluminium wire
as shown in figure. The size of the steel core and of the Aluminium stands is generally same.
Stranded conductor s, rather than a single conductor, is used to give flexibility to the
conductor. The steel wires provide the tensile strength, which the Aluminium wires, carries
the current. For higher size of conductor s, the no of steel wire in the core as well as the
number of Aluminium strands increases .In CEB is most used ACSR. (Shown in figure 25(a))
There are two types A.C.S.R. (aluminium conductor steel reinforced) cable is used.
1) “Racoon” 7/ 4.09 mm A.C.S.R Cable
2) “Lynx” 37/ 2.79 mm A.C.S.R Cable
AAC:
These are stranded conductors made of Aluminium wires. Stranded Aluminium conductors
are durable and flexible. Stranded Aluminium conductors are durable and light. Mainly used
of this conductor on low voltage distribution system. Aluminium has conductivity of 60%
that of copper and therefore, for the same resistance and voltage drop in carrying same
current, Aluminium conductor has 1.6 times the cross sectional area of copper.
The density of Aluminium is 2.7 gm/cc as against that of 8.89 gm/cc for copper. Taking
combined effect of low conductivity and low density of Aluminium into account, the weight
of Aluminium required for the same resistance of the line, is nearly half that of copper. This
is big advantage in favor of Aluminium. Moreover, the Aluminium is cheap and easily
available, main drawback of Aluminium is that its ultimate tensile strength is about half that
of copper and therefore, it cannot be used as such for long spans. (Shown in figure 25(b))
Figure 25: ACSR, AAC, Copper Conductors
a cb
~ 47 ~
2.4.8 Typical Conductors materials & Tools
Following materials and equipment are used in the construction branch. The materials used
for constructing a pole mounted substation and HV, MV and LV lines can be categorized as
follows;
Table 02: Material used for LV, MV, HV lines & Sub station
~ 48 ~
2.5 project & Heavy Maintenance Unit
2.5.1 Introduction
The Medium Voltage in Electrical Power system is 33 and 11 kVs. The heavy maintenance
branch of the CEB is responsible for the maintenance of the medium voltage lines, especially
the 33kV, in the whole country. Main tasks carried out by the heavy maintenance branch,
Kandy is;
Routine maintenance
Restoration of supply after major breakdowns in 33kV lines or Primary Subs.
This branch has divided its functions in to three;
Substation & Gantry Maintenance
This is mainly the primary substation maintenance & Gantry maintenance.
Line Maintenance
This can be further divided into Hot line (Live line) maintenance and Cold line maintenance.
Project planning
Planning all the things before installed new tower line.
There is a Chief Engineer who is in charge of the whole activities. Under him there are four
Electrical Engineers who look after the Line maintenance, Line construction project and the
Substation section. There are three Electrical Superintendents under each of the four EEs.
2.5.2 Line inspection, maintenance & construction
Line Inspection:
Before maintain a 33kv distribution line, first we should clearly identify what are the
problems occurred in a tower line. They may be towers, insulators or cables. We should
check whether they are working properly or not. In a line inspection the person who inspects
the line should walk along the distribution line. And he should report everything in an
inspection report. It includes tower type, missing tower plates, tower number, insulators and
cables. After completing the report it is handed over to an authorized person. After going
through the report necessary equipments and instruments are supplied to maintain the
inspected line.
~ 49 ~
Line Maintenance:
After the inspection the maintaining process is going on. Workers should replace insulators
which are damaged and they should tension distribution cables which are sagged.
Line Construction:
Medium voltage over head transmission lines are used to transmit power between two
substations or from mini power stations to the system. While constructing an over head line,
it should be ensured that mechanical strength of the line should provide protection against the
most probable weather conditions. In general the main components of a medium voltage
transmission line are;
Conductors
Supports
Insulators
Miscellaneous items
2.5.3 Line stringing & jointing
Line stringing
The tension method of stringing is employed for 33 kV lines where it’s necessary to keep the
conductor off the ground to minimize surface. Its necessary to keep the conductor off the
ground to minimize surface.
A pilot wire was first payed out in the same manner as earth wire except that the pilot wire
was passed through the rollers/travelers fixed on the cross arms.The pilot wire was then
used to pull in the conductors from the reel stands using specially designed tensioners &
pullers.
While running out of the conductors, care should be taken such that conductors don’t touch &
rub against the ground or objects which could cause scratches or damage to the strands. The
conductor shall not over strain during erection. The conductor drum was jacked upon a steel
shaft on a drum jack. The conductor shall be run out of the drums from the top in order to
avoid damage due to chafing. (Shown in figure 26)
~ 50 ~
Jointing
Joints
Mid span Joints Non-tension Joints
Mid span joints (Shown in figure 26) are used to connect two lengths of overhead line
conductor together between the pylon towers & are classed as overhead tension joints.
Tension joints are available in the majority of commonly used overhead line conductors.
If the conductor drum finished or conductor damaged, the mid span joints are used for the
connect the two conductor together. The Al tube portion of the mid span joint was slipped on
to one of the conductor. A mark was made on the conductors at a distance from their open
ends which are equal to half the length of the steel tube portion plus its elongation during
compression. The conductor strands were tied up near this mark with two rounds of binding
wire. The Al strands were cut at these marks to expose the steel core, taking care not to nick
the steel strands. The steel strands were tied up with a least two rounds of binding wire as the
Al strands were cut off.
Figure 26: Line stringing moment Figure 27: Joint compression mid span-LT
~ 51 ~
The two ends of the steel core of the conductors were inserted into the steel tube of the mid
span joint making sure that the ends are at the center of the steel tube, i.e.; equal lengths of
the steel cores of both the conductors remain outside the tube. The steel tube was then
compressed, beginning from center & then first one side & then the other side, to the
specified load & dimensions. Any sharp edges or burrs remaining after compressing the steel
tube were filed off to give a smooth finish. Grease was applied on the compressed tube.
Same as Al strands of the conductors were cleaned, particularly in the case of old &
blackened conductors. The Al tube was slipped over the steel joint taking care to ensure that
the center of the tube is in the center of the joint. Then the Al tube was compressed to the
specified load & dimensions except the portion between the holes which is marked as
“uncompressed Zone”. The compression was started from the end of the “Uncompressed
Zone” & then worked towards the end of the Al tube. Any sharp edges or burrs remaining
after compressing the Al portion were filled off to give a smooth finish.
2.5.4 Selection of towers
There are many types of line supports but steel towers are commonly used for medium
voltage lines.
Steel towers
Steel towers have grater mechanical strength; longer life can withstand most severe climatic
conditions and permit the use of longer spans. There are several types of steel towers used for
medium voltage lines. Description of each tower is given by three letters Such as TDM etc.
First letter describes the height of the tower it can be T (Tower), M (Mast) or Z. Each letter
represents a different height. But the height of the tower can be increased by a small amount.
Height of the tower is important to the length of the span.
Second letter describe the number of circuits supported by the structure;
1) S -Single circuit.
2) D -Double circuit
~ 52 ~
Third letter describe the position of the tower.
L- Line tower (Suspension) M-Medium angle tower (00<angle<300)
H-Heavy angle tower (300<angle<600) T-Terminal tower (Dead End)
Fourth letter describe the body & leg extension of the tower.
Body Extension= +0, +3, +6
Leg Extension= +1, +2, +3, -1, -2
Ex- TDH+3
Body & Leg extension +3
Tower type Heavy angle
Double circuit
SCSP DCSP DCT SCT DCT G-VSCT SCSP SCT
2.5.5 Primary substation
Primary substation plays a major part in medium voltage distribution. Main function of the
primary substation is to convert 33kV supply to 11kV supply and distribute the supply to
consumers. Primary substations receive electricity from grid substation, In order to provide
consumers with continuous supply receive electricity from more than one feeder. Most of
them receive supply through overhead lines. Some receive supply through underground lines.
Output is also given through more than one feeder. During my training period I observed
about two different types of substation.
1) Outdoor substation
Figure 28: Various kind of line supports
~ 53 ~
2) Indoor substation
Outdoor Substation:
This type of substations has an outdoor switch yard. Switch yard consists of breakers,
isolators, bus bars, insulators, current transformers; potential transformers etc. supply is
transmitted in open conductors therefore considerable amount of space should be kept
between conductors. There for large area is needed to construct an outdoor substation. But
repairs and maintenance of outdoor substation is easier than indoor substation, But operation
of outdoor substation is difficult than indoor substation.
Indoor Substation:
Indoor substations are only used up to 11kV voltage. This type of substations does not have
any outdoor switch yard. Only transformers are installed outside. Both incoming and
outgoing supplies are given through underground cables to bus bars. Bus bars are installed in
the power panel in the substation. In order to reduce the size of the panel 33kV bus bars are
kept in pressurized gas (SF6). 11 kV bus bars are kept in vacuum.
Figure 29: Outdoor Substation Figure 30: Indoor Substation
~ 54 ~
2.5.6 Parts of a primary substation
Transformers:
This is most important part of the primary substation. Power transformers installed in the
primary substation are three phase step down transformers. There are two types of
transformers in the substation.
1) 33kV to 11kV Transformers
2) 33kV to 415V Transformers
Bus bars:
When number of lines at the same voltage has to be directly connected electrically, bus bars
are used as common electrical component. Bus bars are copper or aluminium bars and
operate at constant voltage. The incoming and outgoing lines in a substation are connected to
bus bars.
Basically this bus bar arrangement is classified in to five parts. There are;
1) Single
2) Double
3) One and half
4) Ring
5) Mesh (complicated ring system)
Bus section:
Bus section is a breaker which it can connect and disconnect both side of bus bar.
Bus coupler:
Bus coupler is the circuit breaker which it can connect and disconnect two bus bars.
Figure 31: Various types of bus bars arrangement in Indoor & Outdoor substation
~ 55 ~
Surge arrestors:
Surge arrestors are guards the primary substation against excessively high voltages
which can imposed on transmission lines by direct lighting strokes. This voltage can
cause flash over across insulators on lines and insulation failure of the transformer
can be happen. The arrestor should have the capacity to discharge the high current
impulse , which can accompany with high voltage. (Shown in figure 32(a))
Voltage transformer:
The capacitor voltage transformer consists of a capacitive potential divider and an
inductive medium voltage circuit . the inductive part is immersed in mineral oil and
scaled with an air cushion inside a steel tank. One two or three capacitor units are
mounted on the steel tank and are used as capacitive potential divider . They consists
of a capacitor stack made from paper film dielectric impregnated in transformer oil
with a metal below cushion and are sealed.
Current transformer:
When a current needs to be measure in a very high voltage circuit ,ammeter cannot
be directly connected across the circuit. In such cases the current transformer is
connected to the circuit and then the ammeter is connected across the terminals of
the CT. At the same way CT are used to supply signal to the overload trip coils of
circuit breakers and to protective relays of all kinds of circuit breakers and protective
relay.
DDLO (Drop Down Lift Off):
An expulsion fuses in a holder, arranged in such a way that the expulsion fuse tube drops out
of the electrical circuit when the fuse has operated. These are commonly used in the CEB
distribution network mainly for the protection of distribution transformers and some cases for
sectionalizing spur MV lines. (Shown in figure 32(c))
Air break switch:
A switch device, which is normally, only used as a disconnection, i.e. only operated in a de
energized system. However a very limiting, making and breaking performance. Contact
velocity at making is operator dependent; an arcing horn may give a high arcing contact
~ 56 ~
velocities at oppugn sufficient for the interruption of load transformers. The switch can in
most cases be equipped with a load current interrupting device. Still, the switch has only very
limited making performance .In the CEB, the ABS were installed in area boundaries,
interconnection points and on long spur line etc. to facilitate isolation of section for fault
location, maintenance and repair works.
Load break switch:
The so-called “general purpose” switch is according to standards defined as follows;
mechanical switching device capable of making, carrying the breaking currents under normal.
A circuit condition, which may include specified operating overload conditions, such as those
of a short circuit.
It may also be capable of as those of a short circuit. It may be capable to making but not
breaking of short circuit current. The load break switch contains some special arts .One of the
interrupter head. It reduces their formed, when the switch is operated.
Line isolators:
Line isolators are used to isolate two zones of power line. And it is a mechanical device
which is able to disconnect two zones. But before isolate the zone breaker must be break first,
other vice huge arc will occur between isolating terminals and it will damage the isolator. It is
very important to isolate when doing inspection or repair in a substation. It provides provide
safety of the working staff. Isolators should operate after making the circuit breaker to the
open position. To make sure not to operate isolating switch before open the circuit breaker,
most isolating switches locked in the close position of circuit breaker. Most old isolating
switches are of manual operating type and new ones have improved to motor operated type.
SF6 Circuit Breakers:
These totally enclosed circuit breakers, insulated with SF6 gas. These are used whenever
space is less, such as in underground substations and power stations. These circuit breakers
are much smaller than any other type of circuit breakers of equivalent power and are less
noisy than others. (Shown in figure 32(b))
~ 57 ~
Oil Circuit Breakers (OCB):
Oil circuit breakers are comprises of a tank filled with insulating oil. In OCBs there are fixed
and movable contacts. It has 3 porcelain bushings, 3-phase line current set to fixed contacts.
Three movable contacts actuated simultaneously by an insulated rod, open and closed the
circuit. When the circuit breaker is closed, the line current of each phase penetrate the tank by
means of a porcelain bushing, flow through the first fixed contact to the second fixed contact,
and then out by second bushing. If an overload occurs, the tripping coil release a powerful
spring that pulls the Insulated rod, causing the contacts to open. As soon as the contacts
separated, an arc is created, which volatilized the surrounding oil. The pressure of the hot
gases creates turbulence around the contacts. This causes cool oil to swirl around the arc, so
that the arc we extinguished. (Shown in figure 32(d))
Figure 32 (a): Surge Arrester Figure 32 (b): SF6 Circuit Breaker
Figure 32 (c): Drop Down Lift Off Figure 32 (d): Oil Circuit Breaker
~ 58 ~
2.5.7 Hot line maintenance
In the CEB hot line maintenance is a one of critical task which can be harmful to life also. In
my training period I was able to observe the 33 kV hot line maintenance (Changing of tower
insulators). For this maintenance specialized equipments & tools are used. Hot line
maintenance can be categorized in to 3 methods according to using method to do that. Those
are;
Hot line maintenance
Hot Stick Method Combination of bothBare-Hand Method
Hot Stick Method
Linesman will be at ground potential working with hot sticks (tools) keeping safety clearance
from the line.
Bare-Hand Method
Linesman works with his covered hands at line potential keeping safety clearance from
ground. For this conducting suits made of 25% microscopic stainless steel & 75% “Nomex”
are being provided.
Combination of both
This method is the combination of above two methods.
Number of special equipments are used for the hotline maintenance. Those are;
Tower Saddle
Wire Tong
Cotter Key Pusher
Link Stick
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2.6 Central Work Shop
2.6.1 Introduction
In CEB I was able to train at the work shop at Aniyakanda. An Electrical Superintendent
supervises the repairing and rewinding of the motors and fans, carrying out the wiring and
checking various electrical quantities. They do motor rewinding, insulation resistance
checking, insulation paper replacing etc. All the repairs of vehicles belong to CEB is done in
mechanical work shop.
2.6.2 Insulation Materials
Insulation materials are materials which offer high resistance to flow of current and are used
in all electrical equipment to confine the flow of current to specified paths. It is the insulation
part in any cable or machine that is the most liable to fail. Apart from the electrical and
mechanical stresses, heat plays the most important part in determining the life and
performance of insulating materials, and as such the operating temperature of any part must
never be allowed to exceed the permissible limit.
Classification of Insulating Materials
The insulating materials have been classified according to their ability to withstand heat. The
recognized classes of insulating materials along with their assigned temperature as per I. S.
1271 - 1958 are as below:
Table 03: Class of insulation Vs. Temperature
~ 60 ~
The assigned working temperature for an insulating material is often less than that listed for
its class, because of the influence of several other factors like vibrations, mechanical and
electrical stresses, thickness of insulation, accessibility of insulated parts, methods of
ventilation, type of service and inability to measure the temperature of the hottest spot. There
are many types of insulation papers are used. They are;
Nomax
Milinex
Combine Paper
Plesban
Luminex
Mica
Combined paper used in motors which are in transformer oil baths. Mica is the best insulation
paper but very expensive.
2.6.3 Electrical Motors
An electric motor converts electrical energy into kinetic energy. The reverse task, that of
converting kinetic energy into electrical energy, is accomplished by a generator or
dynamo. In a rotary motor, the rotating part (usually on the inside) is called the rotor, and
the stationary part is called the stator. The rotor rotates because the wires and magnetic field
are arranged so that a torque is developed about the rotor's axis. The motor contains
electromagnets that are wound on a frame. Though this frame is often called the armature,
that term is often erroneously applied. Correctly, the armature is that part of the motor across
which the input voltage is supplied. Electric motors can classify as D-C Motors and A-C
Motors.
2.6.4 Motors Winding & Rewinding
I was able to observe how a ceiling fan motor winding was carried out. I was able to observe
how to do the starting winding & running winding of this motor. In the winding procedure
extreme care was taken by the workers to not to damage the insulation of the copper
conductors. Further I was able to observe different types of insulators which had been used
~ 61 ~
depending on the temperature of the equipment and other relevant factors. For proper
tightening of the winding a paste of varnish was applied and then the heat was supplied to
provide the rigid look to the motor. Resistance was checked after the winding for
inconsistencies of the insulation using a megger.
Types of winding connection (3 phase):
Star Connection
Delta Connection
Star Connection:
The Star connection is defined as where the finishes of each phase are connected together &
the starts are connected to the line leads.
Delta Connection:
The Delta connection is defined as where the finishes of each phase are connected to the start
of the next phase.
Rewinding procedure:
1) It’s an important in any motor work, to have clean & dry place in which to work.
2) First have to take out winding carefully from the stator.
3) Observed the winding & get an idea about how the winding is done & the pattern of
the winding.
4) Then measure the winding wire’s diameter or gauge & find new wire match with that
remove wire & do the winding accurately.
5) Then the new winding should be checked, before it sends back to the work.
6) Finally, megger the winding for find the insulation condition.
Figure 33: Side view of the winding finished fanmotor
~ 62 ~
2.6.5 The Casting Process
The Al casting wad done using scrap Aluminum from the workshop. As shown in the
apparatus below. Even the process looked simple, when the actual work was carried out there
were some issues could be seen. The fuel for the apparatus was made with the mixture of
kerosene and burned Engine oil. These two were mixed and released to the inlet of the hearth.
For proper burning of fuel a blower is used and the two nozzles were placed closely to each
other as shown in the figure below. (Shown in figure 34(a))
The scrap Aluminum was put in to this special type of cove which is made of graphite and
special type of soil which was able to withstand to extreme heat. Then the cove was kept on
fire until the scrap Aluminum become melted Aluminum. The plastic moulds were fitted with
this special type of soil called “casting soil”. Which was not adhesive with the liquid
Aluminium. The necessary shape was obtained by pouring the liquid Aluminum in to these
molds and letting it to be chilled under environment temperature.
Figure 34(a): Two nozzles at the hearth Figure 34(b): Special type of cove
~ 63 ~
2.7 Power Plant
2.7.1 Introduction
In my training at CEB I was able to train at the Standby Power Plant, Kolonnawa. In here
they Maintain generators under Ceylon electricity board and supply generators for some
important government occasions. In there I observed about the Generators, Alternator, 4-
stroke & 2 stroke diesel engines, Battery maintenance repaired. I briefly observed about the
working principles of diesel engine which was a four stroke & two stroke engines.
2.7.2 Generator
A Generator is a machine which converts mechanical energy in to electrical energy on the
principle that when magnetic flux is cut by a conductor or a number of conductors emf is
induced in the conductor or conductors and the mechanical power supplied by a turbine or an
internal combustion engine is converted into electrical power.
Generator can be divided in to 2 parts;
1) Engine
2) Alternator
Engine:
In general 4 stroke engines are used as prime movers of diesel generators. As implied by the
name, the piston of the engine is subjected to “4 strokes” repeatedly during the operation of
it. They are;
1) Suction Stroke
2) Compression Stroke
3) Power Stroke
4) Exhaust Stroke
The reciprocating motion of the piston is converted in to a rotary motion by the “crank shaft”.
A fly wheel having a large inertia is coupled to the crank shaft. Therefore a part of
mechanical energy produced by the power stroke is stored in the fly wheel. Actually power
stroke is the only Stroke that produces power. During other three strokes, the engine is driven
by the energy stored in the fly wheel.
~ 64 ~
Alternator:
Generators are used as alternate power supply. Generator is operated when there is
No main supply
Frequency less or excess than 50Hz
Difference in voltage
There are two protection types used in a generator, such as mechanical and electrical
protection. Over speed, low oil pressure and high temperature are some of the mechanical
protection methods. Electrical protection can be described as over current and over voltage
protection. Regularly, it must be read the control panel and should take the necessary actions
otherwise generator will fail. Change over switch was used to select the main supply or
generator supply.
There are three basic types of excitation is used in alternators. These are direct self excitation,
indirect self excitation and separate excitation method. The back EMF is occurred when the
generator starts and off. This back EMF cause for large current and affects to diode rectifiers.
The varrister is used to protect the diodes and this high current goes through varrister.
Actuator controls the speed of the generator by controlling fuel. When repairing the
generators, insulation resistance of the windings is tested. It is done by using a megger. Three
insulation tests are carried out.
Continuity Test
Insulation resistance between windings
Insulation resistance between earth and winding.
2.7.3 Battery Maintenance
There is a battery maintaining unit in power plant branch. This unit supplies batteries in good
condition for the diesel generators. Main tasks of this unit are battery recharging and refilling
with 98.5% CON.H2SO4 acid. Gravity meter is used to check the specific gravity of the acid.
Normally batteries are charged by using low ampere current. Acid should be filled into the
battery from negative side to positive side. Otherwise battery will be destroyed.
~ 65 ~
2.8 Safety against Electricity
Electricity makes our day to day lives Comfortable and easier, but can be a deadly hazard if
mishandled. We are committed to providing you with awareness of importance of safety
when using it. Below are some important guidelines for you to follow regarding Indoor and
Outdoor electrical safety.
Indoor Electrical Safety
Do not use electric appliances when you are bathing or standing near a sink.
Unplug all electrical appliances before repairing or cleaning.
Unplug all electrical appliances when not in use.
Unplug an appliance that has fallen into water before attempting to retrieve it.
Do not touch an electrical appliance with a metal object.
Never use any electric appliance on a wet surface, while wet or standing in water.
Make sure your hands are dry when using an appliance.
Use electrical appliances with three-pronged plugs.
Never hang clothes or place furniture near an electric heater or hot plate.
Keep electric heaters at least four (4) feet from furniture and drapes.
Keep electric heaters on a level non-flammable surface.
Never go to sleep with a heating pad or space heater turned on.
Never place appliance cords where they will come into contact with the stove or other
heated surfaces.
Always unplug an appliance that overheats, and have it checked by a qualified repair
person before using it again.
Turn off a light before replacing the bulb.
Never pull out an electrical plug by the cord.
Do not stick any object other than an electrical plug into an outlet.
Replace perished or cracked electrical cords with new ones; you can purchase these at
your local electrical or hardware store.
Keep electrical cords out of walking areas in the home.
Keep electrical cords out from under rugs and heavy furniture.
~ 66 ~
Keep appliance cords safely away from ledges where children and pets can pull them
down.
Do not overload outlets with too many appliances; make use of multiple outlets in the
vicinity.
Use extension cords minimally.
When outside, use only extension cords that are approved for outdoor use.
When replacing circuit breakers and fuses, use the correct size device.
Protect outdoor outlets with protective, weatherproof covers.
Keep outdoor wiring on a separate circuit.
Know the location of the main electrical switch in the home.
Never force a plug into an outlet.
Outdoor Electrical Safety
Never touch a power line. Some overhead power lines appear insulated but only have
weather protection. These are not safe to touch. Touching a power line with any part
of your body or any object such as ladders, tree trimmers, poles, ropes or kites can
result in serious injury or death. Remember that electricity can move through
conductive materials, i.e., water, metal, wood, aluminum, string and plastics. If you
see a wire down, keep yourself and others away and contact CEB Call Centre
immediately at 1987.
Don't work or play near power lines. When carrying long or tall items, such as
ladders, scaffolding, tree saws and pool cleaning equipment, hold them parallel to the
ground to avoid contact with power and other overhead wires. Before you raise them
into the air, make sure they’re clear of any power lines.
Always wear shoes when using outdoor electrical equipment
Maintain proper clearances. For your protection, certain critical clearances are
required by law, and minimum of 10 feet must be maintained when working below or
adjacent to power lines.
Teach children to be safe. Children should stay away from electric facilities such as
substations, transmission towers, transformers and power lines.
Do not climb trees if they are touching or near a power line
~ 67 ~
Protect outside outlets. Make sure that your outside outlets have a ground earth
leakage current interrupter to protect you from potential shock.
2.81 Common safety used in CEB
Electrical hazards cause more electrocutions and injuries in the workplace each year,
disrupting lives and impacting the productivity of companies. While electrical hazards are not
the leading cause of on-the-job injuries, accidents and fatalities, they are disproportionately
fatal and costly. To avoid these electrical hazards, Ceylon Electricity Board has introduced
some safety equipment as below.
1. Head and face protection
Protect the most critical part of the body against impact, injury heat and cold with strong and
durable hard hats.
2. Hearing protection
Preserve hearing sensitivity in noisy work environments with convenient, comfortable ear
plugs, earmuffs and other hearing protection.
Figure 35: Head & Face Protect Hard Hat
Figure 36: Hearing protector
~ 68 ~
3. Gloves
Guard hands against germs, cuts, chemicals, and burns with a full line of disposable and
reusable gloves from popular brands including Mechanixwear, Ansell, G-Tek and more.
4. Eye protectionWorkers can expect extreme comfort and protection with these face-flattering safety glasses
and goggles.
.
5. Safety shoes
Safety shoes and safety boots give an extreme protection for the foot of the workers.
Figure 37: Protective Gloves
Figure 38: Eye Protector
Figure 39: Safety Shoes & Boots
~ 69 ~
CHAPTER 3
CONCLUSION
All students of engineering field must learn both theories and practical correctly. The students
of Higher National Diploma in Engineering learn the lot of theories. After that they should be
studied the applications of that theories and also about the technical side. The best method of
satisfying the second requirement is to give a change to the student to work with the practical
engineering environment.
For achieve this, the ATI and the NAITA have done a great job to conduct industrial training
program for students at relevant and useful industries. Furthermore the knowledge gathered
through lectures is reinforced by the practical knowledge. I got a invaluable training at CEB.
The theories always support not only to make new things, but also to learn about already
made things. However the students need good skills to handling problems in vast area of the
modern industry.
I've got a good opportunity to have my second session of first industrial training in Ceylon
electricity board. CEB is the major power distributor in Sri Lanka. During this valuable
period I was able to take so many experiences about the transmission, and distribution
network of Sri Lanka and I could be able to collect faculty of knowledge with in these three
months of my industrial training. Here I should mention that I was able to get a special
opportunity to work together technicians as well as engineers and share their knowledge and
experiences.
All of the workers were really helpful to me by guiding to get working experience and
educating me to get knowledge about some are new for me. Also the resources that were
available to me were very satisfactory .In my training session I not only gained the technical
knowledge and also got the knowledge about how to dealing with working environment, how
to dealing with the officers & the workers, how to maintaining the stocks in the workshops
and their importance. Those things gave me a really good training as an engineering
diplomat. Since CEB directly deals with consumers, I could be able to get the knowledge
about how to deal with them.
~ 70 ~
But we cannot accomplish the meter lab schedule in our training period. Because that part
was removed our training schedule. If it is included we can gather a lot of knowledge about
the Types of energy Meters, Operation Principle of Single Phase Watt Hour Meter, Tests on a
Single Phase Meter, The kVA meters, Automatic energy meter test system etc.
Likewise if CEB would change their training schedule a little bit in order to get more
practical knowledge on technical side in the generation side also we can achieve accurate
training in the CEB. However I had a good training session at CEB with in my industrial
training. So, it helps me to gain a better experience and work made my training valuable and
successful.
~ 71 ~
REFERENCES
1) Annual Reports & Accounts-2010 Ceylon Electricity Board
2) E-CITY CUSTOMER GUIDE FOR COLOMBO CITY
http://www.metroceb.lk
3) SUPER LINE J SERIES THREE PHASEINDUCTION MOTOR
http://www.mitsubishielevator.com
4) http://en.wikipedia.org
5) Lift and Escalators: Basic Principles and Design
Dr. Sam C M Hui
Department of Mechanical Engineering
The University of Hong Kong
6) Air Conditioning
http://www.freeasestudyguides.com
7) CEYLON ELECTRICITY BOARD
REGION [1] DISTRIBUTION LICENSE
EL/D/09-003
Supply Services Code
8) PWS 2.3 PLUS MANUAL
Three-phase Portable Working Standard for Testing Electricity
Meters and Instrument Transformers
~ 72 ~
9) Pole mounted SF6 Gas Insulated Load Break Switch & FTU-P100-Manual
P&C Technologies Co., Ltd.
10) UltraSL™ Polymer-Housed VariSTAR™ Surge Arrester-Manual
IEC 60099-4 (IEC 99-4) for MV Systems to 36 kV
Installation Instructions
11) GUIDE FOR THE PURIFICATION OF INSULATING OIL
By I.A.R. Gray-Transformer Chemistry Services
12) Overhead Power Lines-Planning, Design, Construction
F. Kiessling • P. Nefzger • J.F. Nolasco • U. Kaintzyk
13) TENDER DOCUMENTS FOR
Construction of 33kV New Line from 132/33kV
Ransinghpur OPTCL Grid Substation to IOCL Depot
At Jatni, Odisha
14) http://www.answers.com/T/Engineering
15) Hastings-Catalog-Hot line tools & Equipments
16) Manufacturing Processes and Equipment
Casting Processes
Prof. J.S. Colton © GIT 2011
17) MAGNAPLUS GENERATOR
280-430 Frame
Installation, Operation and Maintenance Manual
~ 73 ~
ANNEXES
Annex 1- leaves record form
LEAVE RECORD FORM
Name of the Trainee - G.R.S.Wasala Herath.
Industrial Training – 2 nd 3 Months
Training establishment – Ceylon Electricity Board
Leave record:
1 st Month 2 nd Month 3 rd Month
No. of days on leave 0 0 0
Has the leave been approved by the establishment - Yes
…………………………. ………………………………
Date Signature of trainee
Annex 2- training schedule
Training Place Address From To Duration
Lift Branch National Hospital
Colombo 08 13/05/2013 17/05/2013 1 week
AC & Refrigeration Branch National Hospital
Colombo 08 20/05/2013 23/05/2013 1 week
Area Office Mawanella 27/05/2013 07/06/2013 2 weeks
Construction Branch Katugastota 10/06/2013 21/06/2013 2 weeks
Pr. & HM Unit 1 Kandy 24/06/2013 05/07/2013 2 weeks
Pr. & HM Unit 1 Kandy 08/07/2013 19/07/2013 2 weeks
Central Workshop Aniyakanda 23/07/2013 26/07/2013 1 week
Power Plant Kolonnawa 29/07/2013 02/08/2013 1 week
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Annex 3- Training certification
CERTIFICATION
I certify that the following G.R.S.Wasala Herath had been training in Ceylon Electricity
Board as an In –Plant trainee in the period of 13th May 2013 to 02nd August 2013 and this
report is based on the experience and the knowledge he gained on the following sections at
Ceylon Electricity Board.
01) A/C branch- National Hospital Colombo 08.
02) Lift branch- National Hospital Colombo 08.
03) Area Office- Mawanella.
04) Construction Branch- Katugastota.
05) Projects and Heavy Maintenance Unit P 1- Kandy.
06) Projects and Heavy Maintenance Unit P 1- Kandy.
07) Work shop- Aniyakanda.
08) Power plant- Kollonnawa.
NAME : G.R.S.Wasala Herath.
REGISTRATION NO: LAB/HNDE/F/E/2010-2011/141.
COURSE : Higher National Diploma in Engineering (HNDE).
FIELD : Electrical Engineering.
PERIO : 13th May 2013 – 02nd August 2013.
………………………… ...…………………………….
Date Signature of Trainee
………………………… ……………………………….
Date Signature of trainee Engineer/Head
(Ceylon Electricity Board)
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Annex 4- organization certificate
~ 76 ~
Annex 5- Report certification
CERTIFICATION
NATIONAL APPRENTICE AND INDUSTRIAL TRAINING AUTHORITY 2ND THREE
MONTHS REPORT OF HNDE APPRENTICE 2013
Place of Assessment Date of Assessment Field
………………………………………….. ………………………………………. Electrical Power
…………………………………………..
Inspection Report
Name of Examiner Designation Signature
~ 77 ~
Remarks & Additional Notes:
~ 78 ~