CHAPTER ONE
INTRODUCTION
1.1
History of SIWES
SIWES was established by ITF (Industrial Training Funds) in the year 1973 in order to
eradicate the conundrum of deficiency of proper skills set for employment of tertiary institution
graduates by Nigerian Industries. SIWES which stands for The Students’ Industrial Work
Scheme Experience was introduced to be a skill acquisition program to prepare and expose
students of various institutional categories which include colleges of education, polytechnics
and universities for the industrial work situation they would most probably meet after
graduation. SIWES scheme allows students the benefit of familiarizing and being exposed to
the experience and skill that are necessary in handling and managing of equipment and
machinery that are not provided by their respective institutions. (History of SIWES (Students’
Industrial Work Experience Scheme), n.d.).
In 1974, SIWES was officially certified and presented by the Federal Government. The ITF
organization single-handedly funded the scheme during its formative years but as time went
on, the financial involvement became too much to the fund, then in 1978, the fund withdrew
from the scheme. The Federal Government handed over the administration and management
of the fund to the National Universities Commission (NUC) and the National Board for
Technical Education (NBTE). In November 1984, the Federal Government returned
management and implementation of the scheme to ITF. Then in July 1985, the scheme was
taken over by the Industrial Training Fund (ITF) while the Federal Government singlehandedly did the funding. Extracted from (History of SIWES (Students’ Industrial Work
Experience Scheme), n.d.).
1.2
Objectives of SIWES
The principal objectives (culled from Detailed Manual on SIWES Guidelines and Operations
for Tertiary Institutions) of the Students Industrial Work Experience Scheme include:
1) SIWES provides an avenue for students to acquire industrial skills and experience during
their course of study.
1
2) SIWES exposes students to work methods and techniques in handling machines and
3) Equipment that are probably not available during their study of their respective disciplines.
4) SIWES is a platform to apply knowledge learnt in school to real work situations by bridging
the gap between theory and practical application.
5) SIWES enables easy and smooth transition from school by equipping students with better
contacts for future work placements.
6) SIWES introduces students to real work atmosphere that they would most likely meet after
graduation.
Extracted from (History of SIWES (Students’ Industrial Work Experience Scheme), n.d.).
1.3
Importance of SIWES
1) SIWES is a comprehensive learning platform for students in which their employability
skills can be improved.
2) It helps to nurture the leadership ability of the students and gives them the responsibility to
execute and carry out the task at hand.
3) It serves as a revenue that helps to groom the self-confidence of a student and identify their
own proficiency.
Extracted from (Importance of SIWES, n.d.)
1.4 Structure and Activities of Organization of the Training Establishment
1.4.1 Organogram of the Company
2
Fig. 1.0 Organogram of the organization
ADC ELECTRICAL COMPANY LIMITED is a leading Electrical Engineering company
registered in Nigeria. ADC ELECTRIC has completed lots of projects in the oil and gas/petroleum,
food processing, pharmaceutical industries, factories and power plants, high end domestic and
commercial buildings. Their excellence stems from highly experienced and motivated staff, précised
work methods derived from worlds best standards.
Electrical Engineering Services
Design, Construction and maintenance of all Electrical and HVAC systems, Raw and
renewable energy, Fabrication of Electrical Power Panels(LV, MV & HV), Control Panels,
Motor Control Centres. E.T.C.
Instrumentation
Design, construction and maintenance of all Instrument scope of works; Tubing, Instrument
mounting, Calibration, and Process optimization for all process plants and factories.
Technical Services
3
Deals with all electrical and instrument design reviews, third-party inspections and
certifications. demographic test, Thermographic test, All integrity and conformity tests.
Fig 1.1 Photo of ADC Electrical Company, Lagos
CHAPTER TWO
SAFETY AND TOOLS USED IN TRAINING
Safety is the state of being "safe", the condition of being protected from harm or other danger.
Safety can also refer to the control of recognized hazards in order to achieve an acceptable level of
risk.
2.1 Detailed Training on Safety
Safety was an integral and important part of operations at ADC Electrical Company. A lot of
emphasis and lectures was made to train me thoroughly on good safety practice. Here are the
safety practices that I was trained in. I was introduced to concepts such as Save Your Life,
Work at height, Firefighting, working in confined spaces and working with electricity.
4
2.2 Use of Protective Equipment
As trainees, working in areas where there are potential electrical hazards must be provided with and
use electrical protective equipment appropriate for the parts of the body to be protected and the work
performed. Protective equipment must be maintained in a safe, reliable condition and be periodically
inspected or tested. Where the insulating capability of protective equipment is subject to damage
during use, the insulating material must be protected by covering with leather or other appropriate
materials. Nonconductive head protection must be worn wherever there is danger of head injury from
electrical shock or burns due to contact with exposed energized parts. Protective equipment for the
eyes must be worn where there is danger of eye and/or face injury from electric arcs and flashes or
flying objects resulting from electrical.
2.3 PPE Dispensary
I was the following personal protective equipment and lectures on their use.
1) Harness belt: A safety harness is a system of restraints that prevent the wearer from falling
from a height. By wearing the belt or harness the risk of injury from a fall is greatly reduced.
The harness allows the user to attach themselves to a stationary object, therefore ensuring
they will not hit the ground in the event of a fall.
Fig. 2.0 Herness belt
2) Gloves: The workplace can create many hazards for your hands, whether from chemicals,
cuts or burns. Industrial safety work gloves are designed to reduce hand injuries in
complex work environment without hindering the user’s overall dexterity in the field.
They are useful during welding operations and when working with electricity.
Fig. 2.1 Hand gloves
5
3) Overalls: (also called dungarees), usually made denim or chino cloth. It is a type of
garment used as a protective clothing when working. It protects your body and garment
from harmful and harmless liquid spillages. It is also designed to not have hanging or
draping parts that can get entangled in rotating machines.
Fig.2.2 Overall
4) Helmet: This is a firm of protective gear worn to protect the head from injuries. It aids
the skull in protecting the human brain. Useful when working in an area that is prone to
fallen objects.
Fig. 2.3 Helmet
5) Safety Googles: Googles or Safety Glasses are forms of protective eye wear that usually
enclose or protect the area surrounding the eye in order to prevent particulates, water or
chemical from striking the eyes. In welding shaded googles are used to protect the eyes
against flares.
6
Fig. 2.4 Safety Googles
6) Ear mufflers: These are a style of hearing protection that fit around the external ear used
to reduce the transmission of sound from entering the ear canal. Nosie is reduced to a safer
intensity level protecting against noise-induced hearing loss. The Occupational safety and
Health Administration (OSHA) recommends the use of hearing protection devices HPD
when an employee is exposed to an average noise intensity of 85DBA over an 8 hour shift.
Fig. 2.5 Ear Mufflers
7) Safety Boots: (Also known as steel toe boot or a steel capped boot or safety shoe) is a
durable boot or shoe that has a protective reinforcement in the toe which protects the foot
from falling objects.
Fig. 2.6 Safety Boots
On the process of undergoing my industrial training, a lecture on fire as one of the main hazards that
occur in workplaces which could be as a result of unsafe acts was delivered. However, the causes of
fire hazards and its preventive measures were outlined as well as electrical hazards and its preventive
measures.
2.4 Causes of Fire Hazards
The three major components needed for a fire to start burning are;
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1) A source of ignition which could be a cooking equipment, smoking equipment, or electrical
equipment.
2) Fuel (flammable gases, liquids or solids).
3) Oxygen.
Sources of potential fire hazards include;
1. Bad electrical equipment.
2. Inappropriate installation.
3. Materials that are flammable e.g., Candles, gas or liquid fueled open-flame equipment.
4. Mechanical heat and sparks which could be as a result of faulty motor, overheated bearing,
sparks produced by grinding and cutting operations.
5. Arcing or sparking of electrical current.
2.5 Preventive measures of Fire Hazards
The preventive measures are not limited to the undermentioned.
1) Identification of all potential ignition sources in the premises.
2) Taking necessary precautions to avoid the coming together of the three components that
can start up fire.
3) Implementation of control measures such as fire detection devices like smoke alarms and
heat sensors.
4) Make sure to remove or insulate flammable materials during industrial operation such as
welding.
5) Optimization of fire escape possibilities including fire safety training and fire evacuation
plans.
2.6 Electrical Hazards
Electrical burn accidents are those accidents that can cause serious injuries which can occur
at home or at workplace.
The main hazards that are likely to occur while working with electricity are;
1) Contact with live parts can cause electric shock and burns.
2) Fire from faulty electrical equipment or installation and exposure to arcing can result to
injury.
3) Blasts from electrical apparatus or static electricity igniting flammable vapors or
dusts.(Electrical Hazards, n.d.)
4) Old wiring.
8
5) Electric cords that are under carpet.
6) Loose connectors.
7) Poor wiring: This could be as a result of substandard wiring which can lead to electrical
fires and electric shock.
Electric shocks can also lead to other types of injury, for example by causing a fall from ladders
or scaffolds etc.(Electrical Hazards, n.d.)
2.7 Tools and Equipments used during Training
1) Thermographic Camera: A thermographic camera (also called an infrared
camera or thermal imaging camera, thermal camera or thermal imager) is a device that
creates image using infrared (IR) radiation, similar to a normal camera that forms an image
using visible light. In electrical engineering, this device is used for contactless inspection of
an electrical system.
Fig. 2.7 Thermographic Camera
2) Lux meter: Light meters, sometimes referred to as lux meters, are instruments that measure
light levels or light pollution. Light meters are frequently used in workplaces, schools,
hospitals and public places to test if there is an appropriate amount of light within the
environment.
9
Fig. 2.8 Lux meter
3) Clamp meter: A clamp meter is an electrical test tool that combines a basic digital
multimeter with a current sensor. Clamps measure current. Probes measure voltage. Clamp
meters are preferred for measuring high level of current.
Fig. 2.9 Clamp meter
4) Drilling Machine: Drilling Machine is the simplest, moderate, and most accurate machine
tool used in almost all the production shops and tool rooms. Drilling is basically a singlepurpose machine tool as its main purpose is to make holes in the work piece.
Fig. 2.9.1 Drilling machine
CHAPTER THREE
EXPERIENCE GAINED AT ADC ELECTICAL COMPANY
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3.1 Earthing and Lightning Protection System:
Earthing is used to protect you from an electric shock. It does this by providing a path (a protective
conductor) for a fault current to flow to earth. It also causes the protective device (either a circuitbreaker or fuse) to switch off the electric current to the circuit that has the fault.
To achieve an efficient earthing system it is essential that a low electrical resistance to earth is
achieved, using good quality conductors with sufficient cross sectional area to carry the expected
current flow. The conductors must also have a high corrosion resistance and must meet
internationally recognised British earthing standards. A survey is required to determine ground
resistivity.
Soil moisture content: more moisture always reduces soil resistance.
Chemical composition of soil: certain salts and minerals affect soil resistivity.
Temperature: if the ground is frozen its resistance becomes much higher.
The extent of any buried services which could affect the earth termination networks.
Details of metallic service pipes, rails, tanks etc. which may need bonding into the earth system to
prevent the danger of side flashing. The area available to place earth electrodes, this may be limited.
Earth Terminations & Networks An earth electrode should be connected to each down conductor
of a lightning protection system (LPS). Earth rods need an earth inspection housing for periodic
testing of earth resistance. Earth rods are used in most applications and are driven into the ground as
close as is practicable to the structure and the down conductor. They are normally spaced at
specified intervals corresponding to the spacing on the down conductors.
Resistance to Earth: For an LPS the earth termination network as a whole should have a combined
resistance of not more than ten ohms, before bonding to building metalwork. However, the
maximum resistance value for earthing systems is application specific. A single earth rod may not
achieve the required resistance figure and several may be need to be fitted to achieve this; their
combined resistance is proportional to the reciprocal of the individual rod resistances to earth. This
rule holds true as long as each rod is situated outside the resistance area of any other. To ensure this
is the case, it is generally accepted that the minimum spacing between rods should not be less than
their driven length. The expected number of rods required to obtain a particular resistance value, e.g.
ten ohms, can be roughly calculated. To do this the soil resistivity needs to be taken into
consideration. A soil resistivity test will need to be performed. There are several methods used to
11
obtain a lower resistance value: More rods can be driven. Rods can be driven deeper. Ring
conductors connecting rods together underground can be used. Rods of a larger diameter can be
used. Where deep driving is not possible shorter rods with a larger diameter can be used; copper
earth mats and earth plates can be used in place of earth rods. A “crow’s foot” configuration can
be used where parallel connection is not possible. Where high resistance soil conditions are a
problem soil conditioning agents can be used to backfill rod holes. Conductive concrete can be used
to backfill an earth mat. Both effectively increase an electrodes cross sectional area and therefore
reduce its resistance to earth. The international standards also specify the recommended materials
used for all earthing conductors and their dimensions.
3.1.1 Type of Earthing
Following are the types of earthing system used:

Plate earthing

Pipe earthing

Rod earthing

Earthing through waterman

Strip or wire earthing
Plate Earthing
In this type of earthing, a plate made up of galvanized iron or copper is buried vertically at a depth
not less than 3m from the ground level. The dimension needed for galvanized iron plate is
60cmX60cmX6.35mm and that for copper plate is 60cmX60cmX3.18mm.
Pipe Earthing
It is the most common type of earthing system. In this type of earthing system, a perforated pipe
made of galvanized steel/iron of approved length and diameter is buried vertically. The size of the
pipe used depends on the magnitude of current and the amount of moisture content in the soil. The
diameter of the pipe is usually 40mm and length 2.75m for normal soil. The amount of soil moisture
determines the length of the pipe.
Rod Earthing
Rod earthing is similar to pipe earthing. In this method of earthing a copper rod of diameter 12.5 mm
or 16mm diameter galvanized steel or a hollow section of 25mm galvanised iron pipe of length not
12
less than 2.5m is buried vertically underground. The pipe can be buried manually or using pneumatic
hammer. The earth resistance is reduced to a desired value by the embedded electrode.
Earthing through the Water main
In this type of earthing system, the water main (galvanized iron) pipe is used for earthing. The
resistance of the galvanized iron pipes are checked and earthing clamps are used to minimise the
resistance for earthing connection. If standard conductors are used as earth wire, end of the strands
are cleaned. The earth wire must be straight and parallel to water main pipe to make firm connection
possible.
Strip or Wire Earthing
In this type of earthing, a strip electrode of cross section not less than 25mmX1.6mm is buried in a
horizontal trench of depth not less than .5m. If copper is used then the desired cross section is
25mmX4mm and if galvanized steel/iron is used then the desired cross section is 3mm2. When using
round conductors made of galvanized steel or iron, the cross sectional area should not be less than
6mm2. The length of the conductor buried should not be less than 15m.
3.1.2 Materials Needed for Earthing Installation:
1) Copper Electrode: This is classified into Copperbond and Solid Copper earth rod;
Copperbond earth rods offer installers the most of achieving a low earth resistance. Each
rod has a high tensile strength, low carbon steel core. 99.95%pure copper is applied
electrolytically and forms a metallurgical steel core and the copper. This combination makes
the rod ideal for deep driving whilst also provides lasting resistance to corrosion. The threads
are formed by a cold rolling process which ensures strength and maintains the molecularly
bonded copper covering along the full length of the threads. Cold-rolled threads are stronger
than cut-threads.
Fig. 3.1 Copperbond earth rods
13
Solid Copper earth rods are designed for use where extremely high corrosion resistance and
exceptionally long life are required. Solid copper earth rods are produced from solid copper
bar and are internally threaded for jointing. When deep driving a solid copper earth rod the
usual practice is to insert the rod into a bore hole and backfill with either Low-Resistance
Earthing Compound or Bentonite
Fig. 3.1.1 Solid copper earth rods
2) Bare Copper Tape: Copper is used for most earthing installations to link electrodes and also
as down conductors due to its high conductivity, anti-corrosive properties and its flexibility
for use in-air, in-earth and in concrete.
Fig. 3.1.2 Bare copper tape
3) Inspection Chambers: This is used to provide both protection and ease of access for testing
to the earth electrode. Can be equipped with copper earth bar to enable multiple connections.
Fig. 3.1.3 Earth inspection chamber
14
4) Digital Earth Tester: Digital Earth Resistance Tester is a very versatile and handy
instrument for checking Earth Resistance. It consists of the indicator & set of 3 spikes (stake)
and connecting wires. Earth Resistance is measured by putting the spikes in the earth at
distance of 5-10metres and switching ON the instrument indicates the Earth Resistance
directly in ohms.
Fig. 3.1.4 Digital Earth Tester
5) Earth Clamp: These clamps are used for joining earth rods to different sizes of copper tape.
The clamps have a high resistance to corrosion and are mechanically strong to ensure a
lasting connection. The ‘U’ bolt clamps can be used to connect flat tapes and stranded
cables to earth rods, reinforcing bars (re-bar) , hand rails etc.
Fig. 3.1.5 Earth clamps
6) Bentonite: is a moisture retaining clay used as an earth electrode back-fillto help lower soil
resistivity. The clay is a sodium activated montmorillonite, which when mixed with water
swells to many times its original dry volume.
Fig. 3.1.6 heap of bentonite
15
3.1.3 Procedures for Earthing System Installation:

Identify the right location for the earthing installation:
The ground rod is usually driven 8 feet into the ground, also it must not be very close to the
structure so that it interferes with it. The location for earthing installation must be identified
considering these and other factors in the earthing design.

Consider soil resistivity levels and soil treatment:
Depending on resistivity and site conditions, the earth rod can be installed directly into the
ground or earth enhancing compound can be used to improve ground resistance.

Excavate a hole of the required dimensions:
Usually, a hole of 120 to 150mm diameter and 2.4m depth is needed for driving the ground
rod into the soil. This can vary depending on the dimension of the ground rod.
Fig. 3.2 hole dug for earthing

Place the Ground Rod:
Ensure to remove all the packaging material from the rod. Place the rod at the centre of the
hole with the pointed end going deep into the soil.
16
Fig. 3.2.1 placing earth rod in hole

Use of Earth-enhancing Compound:
The earth-enhancing compound must be made into a slurry (semi-liquid mixture) using the
required water. Pour the slurry into the hole and completely fill it to the top. To ensure the
slurry completely fills the hole keep agitating the rod while pouring the slurry.
Fig. 3.2.2 poured bentonite solution

Backfill the hole:
If there is any empty space in the hole or if no earth enhancing compound is used the hole can
be filled with the excavated soil.
Fig. 3.2.3 backfilling the hole

Allow the Earthing Compound to set:
If a compound is used as a backfill, let the compound cure/set in the hole. The earth pit is
17
now ready for use and can be used for earth connections after 1-2 days of installation after
checking the resistance value.
Fig. 3.2.4 after filling up the hole

Installation of Earth Pit/ Inspection Chamber:
Earth pit or inspection housing can be fixed onto the ground rod to protect the rod from
external factors or environmental conditions. It also enables easy maintenance and
inspections in the future.
Fig. 3.2.5 After mounting Earth inspection chamber
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Fig. 3.3 Diagrammatic representation of Earthing system
3.1.4 Measurement of Earth Resistance by use of Earth Tester

For measuring earth resistance, earth tester is used. It is also called “merger”

It has a voltage source, a meter to measure resistance in ohms, switches to change instrument
range. Wires to connect terminal to earth electrode and spike.

It is measured by using three terminals earth tester instrument, the terminals are connected by
wires. As illustrated in Fig. 3.4

Potential spike and current spike. The distance between the spikes may be 1m, 2m, 5m, 10m,
35m etc.

All spikes are equidistant and in straight line to maintain electrical continuity and
measurement taken in different directions

Soil resistivity = 2πLR

R= value of earth’s resistance in Ohms

L= Distance between the spikes in cm

π= 3.142
19

P= earth’s resistivity in Ohms

Earth’s resistance value is directly proportional to the soil resistivity value
Fig. 3.4 Schematic diagram of Earth Resistance Measurement Connection
In this method earth tester terminal C1 and P1 are shorted to each other and connected to the earth
electrode (pipe) under test. Terminals P2 and C2 are connected to the two separate spikes driven in
earth. These two spikes are kept in same line at the distance of 25 meters and 50 meters due to
which there will not be mutual interference in the field of individual spikes. Normally, the length of
wires should be. Suppose, the distance of Current Spike from Earth Electrode D = 60ft, Then,
distance of Potential Spike would be 62 % of D = 0.62D i.e. 0.62 x 60 ft = 37 ft.
3.1.5 Importance of Earthing
The main purpose of grounding is to minimise the unfortunate events like accidents due to electric shock, fire as a
result of current leakage through unsought path and ensure the current carrying conductor’s potential does not
increase with respect to earth than the designed insulation. In certain cases the metallic parts of the electrical
appliances comes in conduct with the live wire, which may be due to the failure of the electrical installation or
cable insulation failure. Charges get accumulated in those metallic parts and a person gets a severe electric shock or
even death when he comes in contact with such charged metallic parts. By means of earthing these charges can be
transferred directly to earth. The following shows the necessity of earthing;
20

Protection of lives of human and animals and also provide safety to electrical appliance and
installations from leakage currents.

In case of fault in one phase the voltage in healthy phase need to be constant.

Protect the electrical system and buildings from lightning.

Provides a return path for electrical traction and communication.

Avoid the fire threat in installations.
3.1.6 Maximum allowable Earth resistance

Major power station = 0.5 Ohm

Tower= 20-30 Ohm

Major Sub-stations= 1.0 Ohm

Minor Sub-station= 2 Ohm

Neutral Bushing = 2 Ohm

Service connection = 4 Ohm

Medium Voltage Network = 2 Ohm

L.T. Lightening Arrestor = 4 Ohm

L.T. Pole = 5 Ohm

H.T. Pole = 10 Ohm
3.2 Lightning Protection
A lightning protection system (LPS) minimise the risk of damage to structures and injury to
personnel by conducting high discharge currents safely to earth. Protection against the secondary
effects of lightning to internal electrical equipment, known as transient over voltage protection is
achieved by the use of transient over voltage protectors; this is in addition to the LPS. A LPS
cannot protect against over voltage transients. Over voltage transient protectors cannot protect
against direct lightning strikes. Both are required for total structural and equipment protection.
The normal strategy in achieving protection is to capture the lightning at a preferred point by the use
of air terminations and conducting it via low impedance down conductors and earth electrodes to a
low resistance earth of less than ten ohms. Air terminations and down conductors are spaced at
regular intervals to form a mesh of conductors around the perimeter of the building and roof, known
as a Faraday cage, and are joined together by specially produced clamps and fixings or welding.
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Fig. 3.5 Lightning Arrestor Connection Diagram
3.2.1 Lightning Protection System Design Considerations
An LPS is designed according to geographical location, local terrain, soil conditions, size and
height of building, type of material used in construction, type of material stored in the building, use
of building and is based on established standards for risk assessment.
3.2.2 Required Earth Resistance For Lightning Protection
For an LPS the earth termination network as a whole should have a combined resistance of not
more than ten ohms, before bonding to building metalwork. However, the maximum resistance
value for earthing systems is application specific.
A single earth rod may not achieve the required resistance figure and several may be need
to be fitted to achieve this; their combined resistance is proportional to the reciprocal of the
individual rod resistances to earth. This rule holds true as long as each rod is situated outside the
resistance area of any other. To ensure this is the case, it is generally accepted that the minimum
spacing between rods should not be less than their driven length. The expected number of rods
required to obtain a particular resistance value, e.g. ten ohms, can be roughly calculated. To do this
the soil resistivity needs to be taken into consideration. A soil resistivity test will need to be
performed. There are several methods used to obtain a lower resistance value: More rods can be
driven.

Rods can be driven deeper.
22

Rods of a larger diameter can be used.

Ring conductors connecting rods together underground can be used.
Where deep driving is not possible shorter rods with a larger diameter can be used; copper earth
mats and earth plates can be used in place of earth rods.
A “crow’s foot” configuration can be used where parallel connection is not possible. Where high
resistance soil conditions are a problem soil conditioning agents can be used to backfill rod holes.
Conductive concrete can be used to backfill an earth mat. Both effectively increase an electrodes
cross sectional area and therefore reduce its resistance to earth. The international standards also
specify the recommended materials used for all earthing conductors and their dimensions.
3.2.3 Lightning Arrester
A lightning arrester (alternative spelling lightning arrestor) (also called lightning diverter) is a device
used on electric power systems and telecommunication systems to protect the insulation and
conductors of the system from the damaging effects of lightning.
Fig. 3.5.1 Lightning Arrestor Rod
The typical lightning arrester has a high-voltage terminal and a ground terminal. When a lightning
surge (or switching surge, which is very similar) travels along the power line to the arrester, the
current from the surge is diverted through the arrester, in most cases to earth.
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Fig. 3.5.2 Connecting the down conductor to Lightning Arrestor on site
3.3 Modern Solar Street Light
The use of Solar Powered LED Street Lights has become an interesting topic of research as
well as application in the commercial world. In today’s application, most of the common
24
High Intensity Discharge (HID) lamps, often High Pressure Sodium (HPS) lamps are being
replaced by more low powered Light Emitting Diode (LED) lamps.
A basic solar powered LED street light system components are:
1. Solar Panel
2. Lighting Fixture – LED lamp
3. Rechargeable Battery
4. Controller
5. Pole
The Solar Panel will provide electricity to charge the battery during day time. The battery’s
charging is controlled by a charge controller. The operation of the LED bulb is controlled by
a control circuit either by using sensors such as Light Dependent Resistor (LDR). All these
components will be fixed on a pole as shown in Figure 3.6. The solar panel is mounted at
the top of the pole to minimize the possibility of any shading on the panels.
Fig. 3.6 Components of a Solar Street Light
25
Therefore, these days street lights has become more modernised as it has been made more
portable and sensitive as Lithium Iron Phosphate (LiFePO4) batteries are being used which are
smaller in size and can be embedded into the solar housing as well as the LED lamp, Programmable
micro processor, controller and sensor, making all the components of a solar street light present in
on a single case as shown above;
Fig. 3.6.1 Ongoing Solar Street Light installation
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3.3.1 Components of a Solar Street Light
3.3.2 Solar panel
A Solar Panel is basically a module that converts light energy (photons) from the sun to
generate electricity in DC form. There are two types of solar panels, mainly crystalline and
thin-film types.
There are two types of crystalline solar panels
(i)
Poly-crystalline Solar Panel
(ii)
Mono-crystalline Solar Panel
As for Thin-film types, there are
(i)
Amorphous Silicon (a-Si)
(ii)
Cadmium Telluride (Cd-Te)
(iii)
Copper Indium Gallium Selenide (CIGS)
(iv)
Dye-Sensitized Solar Cell (DSC)
Fig. 3.6.3
Crystalline based solar panels are commonly used due to its maturity in terms of its
technology and price. Even though poly-crystalline solar panels are cheaper compared to Monocrystalline solar panels, Mono-crystalline panels are preferred in Street lights applications because its
smaller compared to poly-crystalline due to its higher efficiency, making the design for the pole to be
easier and cheaper too.
27
3.3.3 Battery
Batteries are used to store the electricity generated by the solar panel. During the day,
electricity generated by the solar panels are supplied to the battery and/or the load. When
the load demand is higher than the energy received from the solar panels, these batteries will
provide stable energy to the load.
Lithium-Ion (LI) or Lithium-Polymer (LP) Battery Lithium based batteries are considered the
future of batteries used in solar powered systems. This is due to a number of factors such
as high specific energy, high DOD percentage, and higher number of charging cycles.
However, due to its higher cost compared to LA type of batteries, they are still not a
preferred choice.
Fig. 3.6.4 Lithium polymer battery
3.3.4 LED lamp
A LED lamp is a light-emitting diode (LED) product that is assembled into a lamp (or light
bulb) for use in lighting fixtures. LED lamps have a lifespan and electrical efficiency that is
several times better than incandescent lamps, and significantly better than most fluorescent
lamps, with some chips able to emit more than 100 lumens per watt. Like incandescent
lamps and unlike most fluorescent lamps (e.g. tubes and CFL), LED lights come to full
28
brightness without need for a warm-up time; the life of fluorescent lighting is also reduced
by frequent switching on and off. Initial cost of LED is usually higher. LED chips need
Fig.3.6.5 Led lamp of a solar street light
controlled direct current (DC) electrical power; an appropriate power supply is needed. LED
are adversely affected by high temperature, so LED lamps typically include heat dissipation
elements such as heat sinks and cooling fins.
3.3.5 Charge controller
Charge controllers are used to control the charging of the batteries. Since the output from the solar
panels are variable and needs adjustments, charge controllers fetches the variable voltage/current
from solar panels, condition it to suit the safety of the batteries. The main functions of charge
controllers are to prevent over-charging of batteries from solar panels, over-discharging of batteries
to the load and to control the functionalities of the load.
Charge controllers are basically DC-DC converters, where PWM technique (preferred
scheme) is used to regulate the switches of the controller. There are three general types of charge
controller, mainly:
(i)
Simple ON/OFF Controller
(ii)
Pulse Width Modulated (PWM) Controller
(iii)
Maximum Power Point Tracking (MPPT) Controller
Most charge controllers operate at three stages to complete the charging cycle of the batteries.
These stages vary according to different times and battery voltages.
PWM can be employed to control the charging at the stages
(i)
BULK stage
(ii)
ABSORPTION stage
(iii)
FLOAT stage
29
Fig. 3.6.6 Three Stage Charging
a) Typical Charge Controller
b) MPPT Type Charge
Controller
Fig. 3.6.7
3.3.6 Method on using LED in solar powered street light
It is known that there is a significant use of LED as the lighting component for Solar Powered Street
light. This is due to the emergence of new technology in LED driver where more efficient LED
modules are able to perform on-par or better than conventional HID or HPS lamps. There is no
“intelligent” scheme being used or an optimization method of approach in the design. The only
energy-efficient component is the use of LED lamps which is a low powered load compared to the
conventional HID or HPS lamps
3.3.7 Utilising sensors to obtain energy-efficient solar powered street lights
Sensors such as Ultrasonic sensors, IR Sensors and LDR sensors are used to control the LED lamp
functionalities in order to achieve a more energy efficient system.
30
Figure 3.6.7, it shows a solar power management system utilising multi-sensor system to
control the light intensity of the LED. A microcontroller was used to control the charging of the
battery, the temperature compensation and also the system.
Fig. 3.6.8 Configuration of Solar Power Management System
3.3.8 Algorithm for LED Lamp Controller
Figure 3.6.8 shows the proposed algorithm for controlling the light intensity of the LED Lamp. The
algorithm starts by checking the real time clock. If the real time is between 0600 and 1800 (during
daytime), the LED lamp will be in OFF state. Once the time is between 1800 and 0600 (at night
time), the algorithm starts with checking the motion sensor input. If there is no input from the motion
sensor, the LED lamp will be at ON state, but its light intensity only at 70% or 14W. Once there is an
input from the motion sensor, the LED lamp will be at ON state at 100% or 20W. At this point a
timer will start counting from 0s to 10s. In between the 10 seconds, if there is input from the motion
sensor, the timer will reset to 0 seconds and the LED lamp will continue to light at 100%. The loop
goes on until there is no input from the motion sensor within the 10 seconds timer. After 10 seconds,
the LED lamp will decrease its light intensity back to 70% or 14W.
31
Fig. 3.6.9 Proposed Algorithm for LED Controller
3.3.9 Data Processing based on Proposed Algorithm
In order to obtain the new load profile for the LED lamp, we need to process the data from the
motion sensor based on the proposed algorithm presented earlier. All thirty days of data needs to be
processed then added up to get the average time per month. This average time is the time when there
are movements around the street light which requires its LED lamp to light up at 100%. The
remaining hours are the time when the LED lamp lights up at 70% only.
Table 3.1 shows additional columns “ADDITIONAL TIME”, “NEW TIME END” and “NEW
TOTAL TIME”. Column “ADDITIONAL TIME” adds 10
seconds to the total time following the proposed algorithm. “NEW TIME END” shows the new end
time after 10 seconds addition while “NEW TOTAL TIME” is the previous total time added with the
10 seconds timer.
Table 3.1: Motion Sensor Data Processing (add 10 seconds to TIME END)
TIME
START
01/06/22 18:05:11
TIME
END
18:05:16
01/06/22 18:07:07
18:07:15
00:00:10
18:07:25
00:00:18
01/06/22 18:07:25
18:07:31
00:00:10
18:07:41
00:00:16
DATE
ADDITIONAL NEW
NEW TOTAL
TIME
TIME END
TIME
00:00:10
18:05:26
00:00:15
32
01/06/22 18:08:00
18:08:31
00:00:10
18:08:41
00:00:41
01/06/22 18:08:45
18:09:02
00:00:10
18:09:12
00:00:27
01/06/22 18:09:45
18:09:51
00:00:10
18:10:01
00:00:16
01/06/22 18:10:10
18:10:16
00:00:10
18:10:26
00:00:16
01/06/22 18:11:01
18:11:15
00:00:10
18:11:25
00:00:24
01/06/22 18:11:35
18:11:45
00:00:10
18:11:55
00:00:20
01/06/22 18:12:10
18:12:35
00:00:10
18:12:45
00:00:35
01/06/22 18:13:30
18:13:47
00:00:10
18:13:57
00:00:27
01/06/22 18:14:23
18:14:29
00:00:10
18:14:39
00:00:16
18:14:40 18:14:48
00:00:10
18:14:58
00:00:18
01/06/22
01/06/22 18:15:02
18:15:30
00:00:10
18:15:40
00:00:38
01/06/22 18:16:00
18:16:06
00:00:10
18:16:16
00:00:16
01/06/22 18:16:10
18:16:18
00:00:10
18:16:28
00:00:18
01/06/22 18:16:40
01/06/22 18:17:10
18:16:57
18:17:17
00:00:10
00:00:10
18:17:07
18:17:27
00:00:27
00:00:17
01/06/22 18:17:25
18:17:50
00:00:10
18:18:00
00:00:35
01/06/22 18:18:39
18:18:47
00:00:10
18:18:57
00:00:18
Table 3.2 shows column “TIME DIFFERENCE”. Here it is the difference between the Time Start of
the motion sensor and the previous Time End of the motion sensor. From the sample below, there are
eight instances (row highlighted yellow) where the Time Difference is 10s and below or already
overlapping(########). Overlapping happens because of the addition of 10s in the previous table,
where the TIME START has passed the previous TIME END. Here from the algorithm, the LED
light should still continue to light at 100% because of the Timer count. Now, for the row where its
time difference is less than or equal to 10s, the NEW TIME END value is brought up to the previous
row’s NEW TIME END. The highlighted row then is removed. Same goes for the row with time
difference “#######”, its NEW TIME END value is brought up to the previous row and the
highlighted row is removed from the table.
Table 3.2: Motion Sensor Data Processing (with TIME DIFFERENCE)
33
TIME
START
NEW
TOTAL
TIME
00:00:15
TIME
DIFFERENCE
DATE
01/06/22 18:05:11
NEW
TIME
END
18:05:26
01/06/22
18:07:25
00:00:18
00:01:41
18:07:41
00:00:00
00:00:19
01/06/22
01/06/22
18:07:07
18:07:25
18:08:00
18:08:41
00:00:16
00:00:41
01/06/22
18:08:45
18:09:12
00:00:27
00:00:04
01/06/22
18:09:45
18:10:01
00:00:16
00:00:33
01/06/22
18:10:10
18:10:26
00:00:16
00:00:09
01/06/22
18:11:01
18:11:25
00:00:24
00:00:35
01/06/22
18:11:35
18:11:55
00:00:20
00:00:10
01/06/22
18:12:10
18:12:45
00:00:35
00:00:15
01/06/22
18:13:30
18:13:57
00:00:27
00:00:45
18:14:39
00:00:16
00:00:26
01/06/22
18:14:23
01/06/22
18:14:40
18:14:58
00:00:18
00:00:01
01/06/22
18:15:02
18:15:40
00:00:38
00:00:04
01/06/22
18:16:00
18:16:16
00:00:16
00:00:20
CHAPTER FOUR
PROJECTS CARRIED OUT
During the course of my IT, I was involved in a lot of projects and electricity installations such as:
 Street light installation
 Earthing system installation
 Lighting protection installation
 House maintenance
 Cathodic protection
 Conduit wiring etc
 Solar installations
 Electrical inspection
Here are some pictures taken during the course of my training:
34
Fig. 4.0 Myself and a colleague during Earthing installations
Fig. 4.1 Myself and colleagues during Lightning arrestor installation
35
Fig. 4.2 Casting the basement of a streetlight pole
Fig. 4.3 Coupling a streetlight to be mounted
CHAPTER FIVE
36
SUMMARY
5.1 Relevance of the Industrial Training to my Course of Study

It gives students the opportunity to apply the knowledge and skills they have acquired in a
real-life work situation.

It provides students with opportunities for practical, hands-on learning from practitioners in
the students’ field of study.

It gives students work experience while they are studying their chosen subject.

It S students to the work environment, common practices, employment opportunities and
work ethics in the relevant field.

It inculcates soft skills relevant to the needs of employers.

It provides opportunities for students to be offered jobs in the same organisations where they
undergo Industrial Training
5.2 Challenges Encountered During The Course Of Training

MEMORIZING THE NOMENCLATURE AND CLASSIFICATION OF TOOLS
It took me a significant amount of time to get used to the names and the classifications of
the tools we used. I had trouble working at my boss’s pace because of this. Fortunately,
over a short period, I completely understood the tools and can now tell which is which
even just by feeling.

MISHANDLING OF LITTLE PARTS AND TOOLS
Never have I been tasked with the responsibility to carefully track and keep very tiny
materials even while working, and working fast at that. At the beginning I lost some
tools, and I used to misplace parts of generators. Fortunately, over time I became better.

WORKING WITH CORRODED BOLTS AND NUTS
I had to get used to working with corroded bolts and nuts. Sometimes they can be very
difficult to handle and can even dull the edges of your fastening tool. You may know what
you need to do to get a broken down machine up and running but if you don’t know how to
lose those nuts, your knowledge would be as effective as none.

LACK OF SPEED
37
At the beginning I was very slow because I was trying to understand the working of
things, my boss had issues with me because of this. With time however, my speed increased
very appreciably.

LACK OF FINANCE FOR MY TRANSPORT FARE
I get discouraged sometimes due to the fact that I don’t get paid, thereby faced with the
challenge of not being able to transport myself from home to my place of training.
5.3 Suggestions for improved SIWES Programme

IT students should be entitled to monthly stipends that will definitely motivate most students
towards learning.

Students that were able to develop new skill/s should properly be awarded by SIWES.

IT students should be given the liberty not to go for trainings on weekends, in order to
rejuvenate themselves for the coming week.
 Routine orientations should be given to students by Industry based supervisors such that IT
students have a proper understanding of what their respective Industrial Training Company is
all about.
5.4 Conclusion
This industrial training has afforded me the basic practical and theoretical knowledge that I
may not have gotten from the lecture room. It has also given me the opportunity to know
what it looks like in the real world to be an electrical and electronics engineer, to have a feel of
what it would be like after graduating.
38
REFERENCES

Fathi, M.; Chikouche, A.; (2010), “LEDs Application to the Photovoltaic
o Street Lighting” International Conference on Renewable Energies. pp.
o 101-104.

Guijian, W.; Yingchun, Z.; (2011). “A New Intelligent Control Terminal of
o
Solar Street Light” International
Conference on Intelligent Compugation Technology and
Automation. pp. 321-324

Jha, A.R. (2010).“Solar Cell Technology and Applications.” U.S, CRC Press.
[4]
Patel, M.R. “Wind and Solar Power Systems”, New York, CRC Press.

Kiehne, H.A. “Battery Technology Handbook”, 2nd Edition, Germany, Merkel Dekker Inc.

A.N. WALLIS- Earthing & Lightning Protection Product Catalogue

dehn-catalogue-lightning-protection_3

Earthing in electrical network - purpose, methods and measurement https://electricalengineering-portal.com/earthing-in-electrical-network-purpose-methods-and-measurement

Electrical Earthing | Grounding | Electrical Tutorials |Mepits | Mepits
https://www.mepits.com/tutorial/497/electrical/electrical-earthing-grounding

Ground Rod Installation - Step by Step Procedure Explained https://axis-india.com/groundrod-installation-procedure/?amp=1

https://www.google.com/search?q=lightning%20protection%20connection%20diagram&tb
m=isch&hl=en&tbs=rimg:CQzqMdPo73eYYYTtY5o4_1oGy8AEAsgIMCgIIABAAOgQIABA
A&client=ms-android-xiaomirvo3&prmd=isvn&sa=X&ved=0CBQQuIIBahcKEwjIuave2ML7AhUAAAAAHQAAAAAQBg
&biw=393&bih=736#imgrc=bdgDxyFNIeBvsM&imgdii=h7_04Ea-mZWtdM
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