Fitter Electrical Assembly RPL Participant...
Transcript of Fitter Electrical Assembly RPL Participant...
Fitter – Electrical Assembly RPL Participant Handbook
Fitter – Electrical Assembly
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Table of Contents
S.No. Modules and Units Page No.
1. Introduction 2
Unit 1.1 – Role of Fitter – Electrical Assembly 3
2. Occupational health and safety (OHAS) 4
Unit 2.1 – Hazard 5
Unit 2.2 – Safe working practices 8
Unit 2.3 – Emergencies and first aid procedures 11
Unit 2.4 – Reporting and documentation 15
3. Basic principles of electricity 17
Unit 3.1 – Basic principles of electricity 19
4. Tools, Measuring instruments and Machines required 23
Unit 4.1 – Tools and measuring instruments required 24
Unit 4.2 – Electrical components and machines 27
Unit 4.3 – Electrical symbols 34
5. Assembly and testing of electrical machine 39
Unit 5.1 – Assembly of electrical machine 40
Unit 5.2 – Testing 45
6. Work effectively with others 48
Unit 6.1 - Effective communication at work place 49
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1. Introduction
Unit 1.1: Role of Fitter – Electrical Assembly
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Unit 1.1: Role of Fitter – Electrical Assembly
Career as an electrical assembler
An electrical equipment assembler, also known as a fabricator, mounts, connects, assembles and
secures parts and components of electrical equipment. The assembler works behind the scenes to bring
together the pieces of equipment we use every day, such as motor, generator, electrical devices and
engines.
A very important part of the job is quality control. Workers must conduct quality checks to identify
faulty components and replace them at the source. Problems need to be fixed as early as possible in the
stream, before large-scale manufacturing of defective products can occur.
Workers mount and fasten parts, align and adjust small components and connect complex wiring. It also
requires fine hand assembly or mechanical parts may need to be assembled onto frames or shelves.
examine detailed drawings to find out job, material and equipment requirements
Lay’s out, positions, and secures parts and assemblies according to specifications.
Set up and adjust electrical and electrical machines and equipment.
fit and assemble metal parts, tools or sub-assemblies.
dismantle faulty tools and assemblies and repair or replace defective parts
Install and repairs equipments
set up and-or operate hand and machine tools
Check accuracy and quality of finished parts, tools or sub-assemblies.
Personal requirements for a fitter job
Following are the personal requirements for a fitter job:
enjoy technical work and have practical ability
be physically fit and have good hand-eye coordination
be able to work independently and as part of a team
have attention to detail
be safety conscious
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2. Occupational health and safety (OHAS)
Unit 2.1 – Hazard
Unit 2.2 – Safe working practices
Unit 2.3 – Emergencies and first aid procedures
Unit 2.4 – Reporting and documentation
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Unit 2.1: Hazards
Hazard
A hazard is something that has the potential to cause injury, disease or death in a workplace. A slippery
floor could result in someone falling and breaking an ankle.
There are a number of aspects to the development of a safe workplace environment:
• the development of policies
• the development of consultative processes
• Hazard identification, assessment and control.
Implications from hazards/risks can be accessed through:
• accident/injury reports
• information on risk from chemicals from data sheets
• review of accident/injury statistics
• information from government health and safety agencies
• Who is exposed, how much, how might they be affected.
Types of Hazard
Physical hazards
During the coal unloading, preparation and handling operations, thousands of tones of coal are
manipulated, producing dust, noise and vibrations. The presence of large quantities of accumulated dust
can produce an explosion hazard in addition to the inhalation hazard.
• During coking, ambient and radiant heat are the major physical concerns, particularly on the
topside of the batteries, where the majority of the workers are deployed.
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• Noise may be a problem in mobile equipment, primarily from drive mechanism and vibrating
components that are not adequately maintained.
Chemical hazards
• The major health concern associated with coking operations is emissions from the ovens during
charging of the coal, coking and pushing of the coke.
• Materials utilized for sealing leaks in lids and doors may also be a concern during mixing and
when lids and doors are removed.
Mechanical hazards
• The mechanical hazards of greatest concern are
associated with the mobile equipment on the
pusher side, coke side and the larry car on top of the
battery. Caught-between and struck-by accidents
associated with mobile rail-type equipment account
for the highest number of fatal coke-oven
production incidents.
• Skin surface burns from hot materials and surfaces and eye irritation from dust particles are
responsible for more numerous, less severe occurrences.
Electrical hazards
The main hazards of working with electricity are:
electric shock and burns from contact with live parts
injury from exposure to arcing, fire from faulty electrical equipment or installations
explosion caused by unsuitable electrical apparatus
Common causes of hazard in steel plant
• slips, trips and falls on the same level and falls from height;
• unguarded machinery;
• falling objects;
• moving machinery, on-site transport, forklifts and cranes;
• exposure to controlled and uncontrolled energy sources;
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• exposure to asbestos;
• inhalable agents (gases, vapours, dusts and fumes);
• skin contact with chemicals (irritants (acids, alkalis), solvents and sensitizers);
• fire and explosion;
• extreme temperatures;
• radiation (non-ionizing, ionizing);
• noise and vibration;
• electrical burns and electric shock;
• manual handling and repetitive work;
• failures due to automation;
• ergonomics;
• inadequate accident prevention and inspection;
• inadequate emergency first-aid and rescue facilities;
Control measures
To ensure the health, safety and security, you have to follow the following methods:
• Carry out assigned tasks and duties in a safe manner, in accordance with instructions, and to
comply with safety rules/procedures, regulations and codes of practice.
• Wear PPE all the time at workplace.
• Obtain and use the correct tools/equipment for the work and not to use any that are unsafe or
damaged.
• Ensure that all guards are securely fixed.
• Not to operate any equipment unless authorized.
• To report any accident, dangerous occurrence or dangerous condition to line management.
• To switch off and secure unattended plant or equipment.
• To avoid improvised arrangements and suggest safe ways of eliminating hazards.
• Always attend the health and safety training sessions organized by organization.
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Unit 2.2 Safe working practices
Safe working practices
Safe practices for avoiding general shop hazards
Never use compressed air to blow chips away from a machine
Keep the floor clear of stock and tools, and clean spilled oils or coolants
Know where the fire extinguisher is kept and how to use it
Always keep machines turned off when making adjustments to them
Things you must do
To make sure that chemicals are stored and handled safely at your workplace you must:
• store the chemicals according to manufacturer instructions
• use and handle the chemicals according to manufacturer instructions
• ensure that stored chemicals cannot mix or react with incompatible substances. This may
include apparently harmless substances, such as dust, air or water
• make provision for containing spillages of chemicals so that they cannot come into contact or
mix with incompatible substances through spillage or leakage, as this may release toxic gases,
cause fire or an explosion
• ensure that chemicals are not allowed to contaminate food, food packaging or personal use
products, including animal food and ingredients for either human or animal consumption
• identify potential ignition sources and ensure they are kept away from flammable chemicals –
this can be done by providing adequate protection or by separation. This is particularly
important if maintenance is carried out involving welding or gas cutting
• ensure that bulk containers for chemicals have stable foundations and supports
• ensure that all risks are controlled when transferring chemicals within, to, or from the premises
• ensure all chemical containers are protected from damage that may be caused by impact, load
or mechanical stress. This includes pipe work, attachments and other equipment
• minimise the risk of fire spreading to or from the chemicals. Providing protection, such as fire-
rated barriers or distances between sheds may assist.
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Personal protective equipment (PPE)
Personal protective equipment serves as the last resort for controlling hazards and is one, but not the
only, ancillary or temporary measure. To make full and proper use of personal protective equipment,
one should first make sure that the equipment can fulfill the working requirements.
Personal Protective Equipment
• Safety helmet: Safety helmets protect the head of the wearer from injuries caused by falling or
wavering objects.
• Earmuffs, earplugs: Earmuffs and earplugs protect the ears of the wearer from injuries by loud
noises.
• Goggles, visor: Goggles and visors protect the eyes of the wearer from
injuries caused by strong light or flying objects.
• Safety boots: Safety boots protect the feet of the wearer from injuries,
puncture wounds and slipping.
• Hand Protection: Gloves should fit snugly. Workers wear the right
gloves for the job (for example, heavy-duty rubber gloves for concrete
work, welding gloves for welding, insulated gloves and sleeves when exposed to electrical
hazards).
Safe material Handling Every worker has to lift and move heavy material during the job whenever required. He may be required
to move the job manually or by using forklift for lifting and moving. Extreme care should be taken while
lifting or moving the job so that no damage occurs to the job or plant and also to prevent accidents at
work place.
• Lifting and moving the job manually
• Lifting or moving the job using fork lift
• Assist in lifting of heavy job
• Attaching the job to the overhead crane’s sling / hook in a proper and balanced manner.
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Points to be taken care of while lifting / moving material
• Lift the materials in correct posture.
• Do not try to lift too heavy materials alone.
• Ensure the grip is right so that the job doesn’t slip from hand and fall
• Put down the job at the destined place properly.
• Do not throw the job on ground.
• Avoid double handling.
• Take rest breaks during heavy or repetitive work
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Unit 2.3: Emergencies and first aid procedures
Dealing with emergency situations
You can encounter emergencies day in day out. Neither should they be ignored nor should you panic. In
case of an emergency,
stay calm;
do not panic;
ensure people around you also stay calm;
inform your immediate supervisor;
if you need to stay with the victim, ask someone from your team to inform your supervisor;
inform supervisor so that the victim receives first aid.
Classification of Fire and Fire Extinguishers
At site, fire may be caused by:
1. heating of metal;
2. electrical heating or short circuits;
3. loose fires caused by welding or smoking;
4. ignition of combustible material;
5. chemical fires;
6. lack of proper housekeeping and/or accumulation of waste.
Tips to Deal with Fire
Keep the work area clean.
Containers with remnants of flammable materials must be filled with water.
Never wear inflammable material like nylon at work.
Ensure there are no unattended cables or wires lying around the work area.
Avoid using power tools near combustible materials.
Avoid using power tools near combustible materials.
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Keep an eye on sparks and metals falling off at all times.
Immediately report about any emergency situation that may cause fire to your senior at work.
Types of Fire Extinguishers
Method of Using a Fire Extinguisher
Free a person from electrocution
It may not be immediately clear, but if you think someone is suffering from electric shock, approach with
extreme caution.
1. The first step is to separate the person from the source of electricity as quickly as possible. The
best way of doing this is to turn off the supply, for example, by unplugging the appliance or by
turning the mains off at the fuse box (consumer unit).
2. If this isn’t possible, then try to remove the source of electricity from the person using a piece of
insulating material, such as a length of wood.
3. Never touch the person receiving the electric shock or you could suffer one too.
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4. After removing the person from the source of electricity, if the person is unconscious call for an
ambulance immediately. Only those with the necessary knowledge and skill should carry out
first aid.
5. Where the person is conscious and seems well, it is still advisable to monitor their condition, as
the effects of an electric shock may not be immediately obvious.
First aid victims in case of bleeding, burns, choking, electric shock,
poisoning etc
Following are some basic first aid procedures for treating shock, bleeding and wounds, burns, choking,
electric shock, eye injury, fainting, heat stroke, hypothermia, and unconsciousness. These techniques
can be used in the workplace or at home and being prepared will help make the most of a serious
situation.
Shock
Shock can be life threatening. Symptoms include cold sweat, weakness, irregular breathing, chills, pale
or bluish lips and fingernails, rapid weak pulse and nausea.
1. Do not give the victim anything to eat or drink.
2. Lay the victim on his/her back, but do not move him/her if there's a back or neck injury. If the
victim is unconscious, vomiting or has severe injury to the lower face or jaw, lay him/her on
his/her side and be sure the victim is getting adequate air.
3. Keep the victim warm (not hot) by use of blankets or clothes.
4. Raise the victim's feet and legs with a pillow.
Bleeding and Wounds
1. Place a clean cloth or gauze and gloved hand over the wound; apply firm, steady pressure for at
least 5 minutes.
2. Elevate an injured arm or leg above the level of the victim's heart if practical.
3. When bleeding stops, secure the cloth with a bandage. Do not lift the cloth from the wound to
check if bleeding has stopped. Be sure the bandage is not too tight—it may cut off circulation.
4. Check the victim for shock.
Burns
1. If necessary, use water to stop actual burning of skin.
2. If the skin is not broken, submerse the burned area under cool running water, or gently apply a
cool compress until pain is relieved. Bandage with a clean, dry cloth.
3. Do not break a blister if one forms.
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4. Do not apply ointments or creams.
5. If skin is broken, or if burns are severe:
o Do not clean the wound or remove embedded clothing.
o Cover the burn loosely with a clean, dry cloth.
o Expect shock and treat accordingly.
Choking
The victim can speak or cough forcibly and is getting sufficient air, do not interfere with his/her attempts
to cough the obstruction from the throat. If the victim cannot speak or is not getting sufficient air, have
someone call on emergency number.
1. Stand directly behind the victim and wrap your arms around the stomach.
2. Make a fist with one hand and place that fist just above the navel and well below the ribs, with
the thumb and forefinger side toward you.
3. Grasp this fist with the other hand and pull it quickly toward you with an inward and slightly
upward thrust. Repeat if necessary.
If the victim becomes unconscious:
1. Lay the victim on their back.
2. If the object that is blocking the airway is visible, reach a finger into the victim's mouth (along
the inside of the cheek) and try to sweep the obstruction out of the victim's throat, being careful
not to push the object deeper into the victim’s airway.
3. Even if this is not successful, attempt rescue breathing.
4. If the victim is still not breathing or moving, begin chest compressions (CPR).
Basic techniques of bandaging
The key points when applying a bandage are:
1. Make sure the person is comfortable.
2. First clean the wound and apply the antibacterial cream over it.
3. Keep the injured part of the body supported in the position it will be in when the bandage is on.
4. Make sure you use the right size bandage.
5. If possible, do not cover fingers or toes when bandaging a limb, so that you can easily check the
circulation.
6. Apply the bandage firmly, but not tightly, and secure the end by folding it over and tying a knot
in the end. You can also use a safety pin, adhesive (sticky) tape, or a bandage clip.
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Unit 2.4: Reporting and documentation
Accidents and incidents reporting
It is extremely important to report accidents and incidents right away, no matter how minor it may be.
Even if the injury is minor or if there is no initial injury and you feel it is not worth reporting, the incident
must be documented.
Reporting and documentation is necessary for several reasons:
• Reporting enables the correction of the situation and helps prevent similar future occurrences.
• If an incident results in long term leave or lost �me and you wish to claim compensation, the
proper documentation is required in order to receive approval.
• For legislative purposes, the accident resulted in serious injury to or the death of a worker must
be reported
Reporting format
Always report an accident to management immediately. There should be a form at each workplace that
you (or the person involved) and any witnesses can fill out, where possible, otherwise it can be
completed by a health and safety representative (HSR) if necessary. The form should cover the following
areas:
Description of the occurrence – what was the event that occurred, which required this report to
be completed?
Nature of injury or disease – select the most appropriate description from a range of options.
What injury or disease happened as a result of the occurrence?
First aid, medical treatment or hospital admission – this section asks for a description of what
was done to treat the injury or disease.
Part of the body affected – tick off which part or parts of the body were affected as a result of
the occurrence.
Source of injury – what actually caused the person to be injured or acquire a disease? This could
be a piece of machinery or other hazardous materials for example.
Probable cause or causes of injury – how was the source listed above actually responsible for
the injury?
Investigation – this asks a series of questions that seek to find out why the person has been
injured or has acquired a disease.
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Notification checklist – this checklist makes sure that everyone who should have been contacted
regarding the matter has been contacted and asks whether appropriate action has been taken
by the authorities.
Preventative action – this asks whether or not any action has been taken to prevent the
occurrence from happening again.
Witness details – this part is to be filled out if someone saw the occurrence happen. It is
essential if any sort of legal action is to be taken.
Filling reports and documents properly
In completing the documentation effectively, follow the established pro-forma. It is important to make
sure that regardless of reporting format, all information is recorded in a manner that is:
written in proper language
correct
timely
According to organization reporting protocols.
The following suggestions will assist you in accurately completing appropriate reports:
Use pen, not pencil.
Do not use erasers or liquid paper. If you need to make a correction, put a line through the word
or phrase and write the correction above it. Initial and date the change.
Be thorough. Write down everything that is important.
Write your notes as soon as practicable after the incident. Most critical incident reports will
specify a time by which the documentation is to be completed.
Use it with particularly important information.
Be legible
In describing an event, be clear, organized and sequential. Write down what happened in the
order it happened.
If you have any concerns about the process of documentation, discuss this with management.
Ensure the report is dated and signed after each entry.
We have looked at a number of aspects of accident/incident reporting, from what we need to report,
e.g. equipment difficulties, damage or malfunction to recording to recording forms required, e.g.
incident reports, fault reports, accident and prevention reports.
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3. Basic principles of Electricity Unit 3.1 – Basic principles of electricity
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Unit 3.1: Basic principles of electricity
Electricity
Electricity is the movement of electrons from one atom to another.
The dense center of each atom is called the nucleus.
The nucleus contains:
Protons , which have a positive charge
Neutrons , which are electrically neutral (have no charge)
Electrons, which have a negative charge, surround the nucleus in orbits. Each atom contains an equal
number of electrons and protons. It is the number of electrons and protons in the atom that determines
the material and how electricity is conducted. Because the number of negative-charged electrons is
balanced with the same number of positive-charged protons, an atom has a neutral charge (no charge).
Conductors, semiconductors and insulators
Conductors: a conductor is an object or type of material that allow the flow of electrical current in one
or more directions. A metal wire is a common electrical conductor. Examples of other commonly used
conductors include:
Silver
Gold
Aluminum
Steel
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Cast iron
Insulators : An electrical insulator is a material whose internal electric
charges do not flow freely, and therefore make it nearly impossible to
conduct an electric current under the influence of an electric field.
Examples of insulators include plastics, wood, glass, rubber, ceramics
(spark plugs), and varnish for covering (insulating) copper wires in
alternators and starters.
Semiconductors: A semiconductor is a substance, usually a
solid chemical element or compound that can conduct
electricity under some conditions but not others, making it a
good medium for the control of electrical current.
Examples of semiconductors include:
Silicon
Germanium
Carbon
Semiconductors are used mostly in transistors, computers, and other electronic devices.
How electrons move through a conductor
Current flow
An electric current is a flow of electric charge. In electric circuits this charge is often carried by
moving electrons in a wire.
The SI unit for measuring an electric current is the ampere.
The following events occur if a source of power, such as a battery, is connected to the ends of a
conductor— a positive charge (lack of electrons) is placed on one end of the conductor and a negative
charge (excess of electrons) is placed on the opposite end of the conductor. For current to flow, there
must be an imbalance of excess electrons at one end of the circuit and a deficiency of electrons at the
opposite end of the circuit.
The negative charge will repel the free electrons from
the atoms of the conductor, whereas the positive
charge on the opposite end of the conductor will attract
electrons.
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As a result of this attraction of opposite charges and repulsion of like charges, electrons will flow
through the conductor.
Circuits
A circuit is a complete path that electrons travel from a power source (such as a battery) through a load
such as a light bulb and back to the power source.
Parts of a circuit
Every complete circuit contains the following parts
A power source, such as a battery
Protection from harmful overloads
(excessive current flow). Fuses, circuit
breakers, and fusible links are examples of
electrical circuit protection devices.
The power path for the current to flow
through from the power source to the
resistance (This path from a power source
to the load—a light bulb in this example—is usually an insulated copper wire.)
The electrical load or resistance which converts electrical energy into heat, light, or motion
A return path (ground) for the electrical current from the load back to the power source so that
there is a complete circuit.
Switches and controls that turn the circuit on and off.
Circuit Fault Types
Open circuits: An open circuit is any circuit that is not complete, or that lacks continuity, such as a
broken wire.
Open circuits have the following features:
No current at all will flow through an open circuit.
An open circuit may be created by a break in the circuit or by a switch that opens (turns off) the
circuit and prevents the flow of current.
A fuse will blow (open) when the current in the circuit exceeds the fuse rating. This stops the
current flow to prevent any harm to the components or wiring as a result of the fault.
Short-to-voltage: A short-to-voltage occurs when the power side of one circuit is electrically connected
to the power side of another circuit.
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A short circuit has the following features:
It is a complete circuit in which the current usually bypasses some or all of the resistance in the
circuit.
It involves the power side of the circuit.
It involves a copper-to-copper connection (two power-side wires touching together).
It may or may not blow a fuse.
Ohm’s Law
Ohm’s law tell us that a current flowing in a close circuit has a direct relationship with the voltage given
to that circuit and is inversely proportional to the resistance of that circuit, provided the temperature
and physical condition is constant.
If, for example, the current ( I ) is unknown but the voltage ( E ) and resistance ( R ) are known, then
Where,
I = Current in amperes (A)
E = Electromotive force (EMF)
in volts (V)
R = Resistance in ohms (Ω)
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Ohm’s law applied to simple circuits
If a battery with 12 volts is connected to a resistor of 4
ohms, as shown in the figure below, how many amperes
will flow through the circuit?
Using Ohm’s law, we can calculate the number of
amperes that will flow through the wires and the
resistor. Remember, if two factors are known (volts and
ohms in this example), the remaining factor (amperes)
can be calculated using Ohm’s law.
Types of electric circuit
Series Circuit: A series circuit is a circuit that has multiple loads and a single
path to go through. Such as a circuit that is connected with a battery and three
light bulbs. First a current has to connect to one load, then the other, and
finally it will flow through the last load and back to the battery. The current can
be calculated with this
Parallel Circuit: Like the series circuit, the parallel circuit passes through more
than one load. However, the circuit gives the current more than one path to
complete the circuit with. Since it has multiple paths, the current will
encounter less resistance by moving through all of the paths at the same time.
Series Parallel Circuit: The type of circuit is a combination of both series and parallel. Electric current
travels through both circuits.
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4. Tools, Measuring instruments and Machines required
Unit 4.1 – Tools and measuring instruments required
Unit 4.2 – Electrical components and machines
Unit 4.3 – Electrical symbols
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Unit 4.1: Tools and measuring instruments required
TOOL USAGE IMAGE
Screwdrivers Screw driver is a tool used for driving in or removing a
screw. To use a screwdriver:
• Select the appropriate tip and size to fit the fastener's
head.
• If required make a starter hole with a drill or by
pressing the tip into the material.
• Insert the screwdriver tip into the screw head and turn
the handle clockwise, applying pressure on the handle
to hold the tip firmly in the head.
• Continue turning the screwdriver firmly and make sure
the screw remains straight as it enters the material.
• Make sure your hand is away from the screw in case
the screwdriver slips off the screw head.
Pliers
• Combination
• Slip joint
• Side cutters
• Long nose
Pliers are used for gripping, twisting and cutting wires. To
use pliers:
• Determine the type of pliers required.
• Then, make adjustments needed to the slip joint, if
any.
• Locking pliers may require adjustment before use.
• Close the jaw around the object by pressing the
handles closer together.
• Rotate the tool as needed to bend or turn the object.
• For safety, make sure that fingers and skin are not
pinched by the handles, pivot, or jaw.
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Hammers
• Ball peen
hammer
• Engineers
hammer
• Soft faced
• Rubber mallet
• Dead blow
• Brass
• Leather
Hammers are used to drive nails, fit parts, forge metal, and
break apart objects. To use a hammer:
• Select the weight of the hammer appropriate to the
fastener to be struck.
• Firmly grasp the lower half of the handle, slowly swing
the head face, and touch the fastener head squarely to
determine trajectory.
• Make sure your hand will not be struck by the hammer
head or handle.
• Then swing the hammer with more force to strike the
fastener head.
• Continue striking the fastener head squarely to drive it
into the material.
Testing Lamps
A test light is a simple but extremely useful tool to
diagnose and troubleshoot an electrical problem.
Ampere Meter
It is used to measure electrical current in an appliance. To
use it break the circuit and attach the instrument to allow
the electrical current to flow through the meter for
measuring.
Volt Meter Volt meter is used to measure AC or DC voltages of
electrical components. This instrument will let you check
to see if there is voltage present on a circuit.
Megger
- Manual
Megger
- Electronic
Megger
The device is used to measure electrical leakage in wire.
The equipment basically use for verifying the electrical
insulation level of any device such as motor, cable,
generator winding, etc. Not necessary it shows us exact
area of electrical puncture but shows the amount of
leakage current& level of moisture within electrical
equipment/winding/system.
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Wire wrapping
tool
Wire wrap is a method to construct electronic circuit
boards. Electronic components mounted on an insulating
board are interconnected by lengths of insulated wire run
between their terminals, with the connections made by
wrapping several turns around a component lead or a
socket pin.
Crimping Tool Crimping is joining 2 pieces of metal or other ductile
material (usually a wire and a metal plate) by deforming
one or both of them to hold the other. The bend or
deformity is called the crimp.
Static Safe
Tweezers
Ideal for picking or placing small electronic components on
SMD and through-hole PCBs, these well-made tweezers
are an inexpensive solution to your soldering needs. The
non-metallic/non-static material makes these tweezers
suitable for use with voltage sensitive devices and reduces
the risk of scratching or damaging components.
Wire Stripper A wire stripper is a small, hand-held device used to strip
the electrical insulation from electric wires.
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Unit 4.2: Electrical components and machines
Understanding of electrical components
Electrical wiring is required in almost every machine so fitter – electrical assembly needs to be familiar
with basic electrical components and equipments used in electrical fittings.
1. Cables: Electric power is transmitted or distributed either by Overhead cables or by underground
cables. Different types of electrical cables are used as per the current load that will pass through the
cable.
Classification of cables
a) Low tension (LT) cable – up to 1000V
b) High tension (HT) cable – up to 11,000V
c) Super tension (ST) cable – up to 33 KV
d) Extra high tension (EHT) cable – 3 KV to 66 KV
Cable carrier and support
The wiring cable can’t be run or laid on
walls without support.
Hence the wires need to be supported
from the main distribution till the
terminating product. The systems used to
carry, support and run these wires are
called cable carriers and support systems.
Different systems are adopted for this
purpose.
2. Switching and terminating products
The major terminating and switching products are house wiring cables normally terminate in:
Switches (All types)
Sockets
Ceiling roses
Holders and adaptors etc.
All these products have certain common features like insulation bases and covers.
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1. Switches: Switches are classified as under:
According to the rating – 6 A, 10 A, 16A
According to the connection – 1 way, 2 way and intermediate
2. Sockets:
According to the rating: 6A, 10A, 16A, 25A etc.
According to the connection: 2 pin, 3 pin, 5 pin, multi pin etc.
3. Ceiling Roses:
The wiring from switch terminals is taken to ceiling roses, lamp holders and connectors.
The ceiling roses are available in two types. These are 2 pin and 3 pin.
4. Holders and Adaptors: There are some other terminating products named as holder and
adaptors. Different holders are available in the market:
Angle Holder b. Batten Holder c. Pendent Holder
d. Screw type / Pin type Holder etc.
3. Cut outs
In electrical distribution, a fuse cutout or cut-out fuse is a combination of a fuse and
a switch, used in primary overhead feeder lines and taps to protect distribution
transformers from current surges and overloads. An over current caused by a fault
in the transformer or customer circuit will cause the fuse to melt, disconnecting the
transformer from the line. It can also be opened manually by utility
linemen standing on the ground and using a long insulating stick called a "hot stick".
Electrical machines
A Fitter – Electrical assembly technician has to deal with many electrical machines. In this section, we
will know about some common electric machines.
Electric motors
An electric motor is an electrical machine that converts electrical energy into mechanical energy.
Working of electric motor mainly depends upon the interaction of magnetic field with current.
When a rectangular coil carrying current is placed in a magnetic field, a torque acts on the coil which
rotates it continuously. When the coil rotates, the shaft attached to it also rotates and thus it is able to
do mechanical work.
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Construction - Parts of a electric Motor
Armature - An electric motor consists of a
rectangular coil made of insulated copper wire
wound on a soft iron core. This coil wound on
the soft iron core forms the armature. The coil
is mounted on an axle and is placed between
the cylindrical concave poles of a magnet.
Commutator - A commutator is used to
reverse the direction of flow of current.
Commutator is a copper ring split into two
parts C1 and C2. The split rings are insulated from each other and mounted on the axle of the
motor. Commutator rings are connected to a battery. The wires from the battery are not
connected to the rings but to the brushes which are in contact with the rings.
Brushes - Two small strips of carbon, known as brushes press slightly against the two split rings,
and the split rings rotate between the brushes. The carbon brushes are connected to a D.C.
source.
Working of Motor - Steps
1. When the coil is powered, a magnetic field is
generated around the armature. The left side of
the armature is pushed away from the left magnet
and drawn towards the right, causing rotation.
2. When the coil turns through 900, the brushes lose
contact with the commutator and the current
stops flowing through the coil. However the coil
keeps turning because of its own momentum.
3. Now when the coil turns through 1800, the sides get interchanged. As a result the commutator
ring C1 is now in contact with brush B2 and commutator ring C2 is in contact with brush B1.
Therefore, the current continues to flow in the same direction.
Electric generators
An electrical generator is a device that converts mechanical energy to electrical energy, using
electromagnetic induction.
Generators are useful appliances that supply electrical power during a power outage and prevent
discontinuity of daily activities or disruption of business operations. Generators are available in different
electrical and physical configurations for use in different applications. In the following sections, we will
look at how a generator functions, the main components of a generator, and how a generator operates
as a secondary source of electrical power in residential and industrial applications.
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Main components of a generator
1. Yoke: Yoke of DC generator serves two
purposes,
It holds the magnetic pole cores of the
generator and acts as cover of the generator.
It carries the magnetic field flux. In small
generator, yoke are made of cast iron.
2. Pole of generator: The field coils or pole coils
are wound around the pole core. These are a
simple coil of insulated copper wire or strip, which placed on the pole which placed between
yoke and pole.
3. Armature of DC generator: The purpose of armature core is to hold the armature winding
and provide low reluctance path for the flux through the armature from N pole to S pole.
Although a DC generator provides direct current but induced current in the armature is
alternating in nature. That is why, cylindrical or drum shaped armature core is build up of
circular laminated sheet. In every circular lamination, slots are either die - cut or punched on
the outer periphery and the key way is located on the inner periphery as shown. Air ducts are
also punched of cut on each lamination for circulation of air through the core for providing
better cooling.
4. Field winding: Armature winding are generally formed wound. These are first wound in the
form of flat rectangular coils and are then pulled into their proper shape in a coil puller.
5. Commutator: The commutator plays a vital role in dc generator. It collects current from
armature and sends it to the load as direct current. It actually takes alternating current from
armature and converts it to direct current and then send it to external load.
6. Brushes of generator: The brushes are made of carbon. These are rectangular block shaped.
The only function of these carbon brushes of DC generator is to collect current from
commutator segments.
7. Bearing: For small machine, ball bearing is used and for heavy duty dc generator, roller
bearing is used. The bearing must always be lubricated properly for smooth operation and
long life of generator.
How does a generator work?
An electric generator is a device that converts mechanical energy obtained from an external source into
electrical energy as the output.
It is important to understand that a generator does not actually ‘create’ electrical energy. Instead, it
uses the mechanical energy supplied to it to force the movement of electric charges present in the wire
of its windings through an external electric circuit. This flow of electric charges constitutes the output
electric current supplied by the generator.
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Pumps
A pump is a device that moves fluids (liquids or gases) by mechanical action.
Pumps operate by some mechanism (typically reciprocating or rotary), and
consume energy to perform mechanical work by moving the fluid.
Basic types of pumps
1. Vacuum Pumps: Vacuum pumps vent the gas from a sealed volume
leaving behind a partial vacuum.
2. Water Pumps: Water pumps pump water. Whether that be in a vehicle, at a business, in the
home, water pump help them draw water from the ground in a self-dug well to be used in
pressure tanks within the location.
3. Trash Pumps: Trash pumps are primarily used to pump wastewater. They are more commonly
used to pump basement bathroom waste up to a higher level for disposal. The wastewater can
contain both hard and soft solids.
4. Hydraulic Pumps: Hydraulic pumps are used in hydraulic drive systems. These pump types can
be labeled hydrostatic or hydrodynamic.
Compressors
Compressors are of two types:
Gas compressor, a device that pressurizes fluids generally
Air compressor, a device specifically for compressing air to
power other tools
Gas compressors
Compressors are similar to pumps: both increase the pressure on
a fluid and both can transport the fluid through a pipe. As gases are
compressible, the compressor also reduces the volume of a gas. Liquids
are relatively incompressible; while some can be compressed, the main
action of a pump is to pressurize and transport liquids.
Gas compressors are used in various applications where either higher
pressures or lower volumes of gas are needed:
In pipeline transport of purified natural gas from the production site to the consumer, a
compressor is driven by a gas turbine fueled by gas bled from the pipeline. Thus, no external
power source is necessary.
Petroleum refineries, natural gas processing plants, petrochemical and chemical plants, and
similar large industrial plants require compressing for intermediate and end-product gases.
Refrigeration and air conditioner use compressors to move heat in refrigerant cycles.
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Gas turbine systems compress the intake combustion air.
Small-volume purified or manufactured gases require compression to fill high pressure cylinders
for medical, welding, and other uses.
Various industrial, manufacturing, and building processes require compressed air to
power pneumatic tools.
Service stations and auto repair shops use compressed air to fill pneumatic tires and power
pneumatic tools.
Fire pistons and heat pumps exist to heat air or other gasses, and compressing the gas is only a
means to that end.
Air compressors
Air compressors are used in various applications:
To supply high-pressure clean air to fill gas cylinders
To supply moderate-pressure clean air to a submerged surface
supplied diver
To supply moderate-pressure clean air for driving some office
and school building pneumatic HVAC control system valves
To supply a large amount of moderate-pressure air to
power pneumatic tools, such as jackhammers
To produce large volumes of moderate-pressure air for large-scale industrial processes (such as
oxidation for petroleum coking or cement plant bag house purge systems).
EOT Cranes
An overhead crane, commonly called a bridge crane, is a type of crane found in industrial environments.
An overhead crane consists of parallel runways with a traveling bridge spanning the gap. A hoist, the
lifting component of a crane, travels along the bridge.
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Operation of crane
1. Before operation, check all parts are lubricated properly and electrical wiring is to be completed
as per wiring diagram.
2. Check that the limit switches cut off the supply to motors in proper direction. In case the limit
switches don’t cutoff the supply in the proper direction make the necessary changes in wiring.
3. Commence lifting the load in stages, starting with not more than 5% of the safe working load &
then increasing this gradually in succeeding trails, till you have reached the full load.
Safe hoisting practices
Do not load beyond the rated capacity. Overloading might also start a defect which could lead to
some future failure even at less than rated capacity.
Do not use any overhead materials handling equipment for handling personnel.
Conduct a periodic visual inspection for signs of damage or wear. Particular attention should be
paid to the cable or chain & hook.
Do not use hoisting cables or chains as a substitute for slings, use slings only.
Stand clear of all loads- If you must travel a load over the heads of other personnel, give ample
warning of your intention before you move.
Limit switches are for emergency use only & should not be tripped during normal operation. if it
is necessary to travel to the limit, use extreme caution & approach the limit in slow speed or by
“inching”.
Be sure the hoist raises & lowers properly when the corresponding push buttons on control
ropes are operated- a reversal of direction indicates a phase reversal in the current conductor,
the reversal of the rope on the drum or an interchange of wires on the push button- any of
which would cause the limit switch to be inoperative.
Centre the hoist over the load before lifting- do not side pull or end pull.
Do not leave the load suspended in the air unattended.
Applications
Overhead cranes are commonly used in the refinement of steel and other metals such as copper
and aluminium. At every step of the manufacturing process, until it leaves a factory as a finished
product, metal is handled by an overhead crane.
Raw materials are poured into a furnace by crane, hot metal is then rolled to specific thickness
and tempered or annealed, and then stored by an overhead crane for cooling.
The finished coils are lifted and loaded onto trucks and trains by overhead crane and
the fabricator or stamper uses an overhead crane to handle the steel in his factory.
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Unit 4.3: Electrical symbols
Wires
Electrical
Component Circuit Symbol Description
Wire
Wire Circuit Symbol Used to connect one component to another.
Wires Joined
Wires Joined Circuit Symbol
One device may be connected to another
through wires. This is represented by drawing
“blobs” on the point where they are shorted.
Un-joined
Wires
Wires Not Joined Circuit Symbol
When circuits are drawn some wires may not
touch others. This can only be shown by
bridging them or by drawing them without
blobs. But bridging is commonly practiced as
there will not arise any confusion.
Power Supplies
Cell
Cell Circuit Symbol Used to provide a supply for a circuit.
Battery
Battery Circuit Symbol
A battery has more than a cell and is used for
the same purpose. The smaller terminal is
negative and the larger one is positive.
Abbreviated as ‘B’.
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DC Supply
DC Supply Circuit Symbol
Used as a DC power supply, that is, the
current will always flow in one direction.
AC Supply
AC Supply Circuit Symbol
Used as AC power supply, that is, the current
will keep alternating directions.
Fuse
Fuse Circuit Symbol
Used in circuits where a probability of
excessive current flows. The fuse will break
the circuit if excessive current flows and
saves the other devices from damage.
Transformer
Transformer Circuit Symbol
Used as an ac power supply. Consists of two
coils, the primary and secondary that are
linked together through an iron core. There
is no physical connection between the two
coils. The principle of mutual inductance is
used to obtain power. Abbreviated as ‘T’.
Earth/Ground
Earth Circuit Symbol
Used in electronic circuits to represent the 0
volts of the power supply. It can also be
defined as the real earth , when it is applied
in radio circuits and power circuits.
Resistor
Resistor
Resistor Circuit Symbol
A resistor is used to restrict the amount of
current flow through a device. Abbreviated
as ‘R’.
Rheostat
A rheostat is used to control the current
flow with two contacts. Applicable in
controlling lamp brightness, capacitor
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Rheostat Circuit Symbol charge rate, etc.
Potentiometer
Potentiometer Circuit Symbol
A potentiometer is used to control the
voltage flow and has three contacts. Have
applications in changing a mechanical angle
change to an electrical parameter.
Capacitor
Capacitor
Capacitor Circuit Symbol
Capacitor is a device that is used to store
electrical energy. It consists of two metals
plates that are separated by a dielectric. It is
applicable as a filter, that is, to block DC signals
and allow AC signals. Abbreviated with the
letter ‘C’.
Variable
Capacitor
Variable Capacitor Circuit
Symbol
Used to vary the capacitance by turning the
knob. A type of variable capacitor is the
trimmer capacitor that is small in size. The
notations are all the same.
Meters
Voltmeter
Voltmeter Circuit Symbol
Voltmeter is used to measure the voltage at a
certain point in the circuit.
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Ammeter
Ammeter Circuit Symbol
An Ammeter is used to measure the current
that passes through the circuit at a particular
point.
Ohmmeter
Ohmmeter Circuit Symbol
Resistance of the circuit is measured using an
Ohmmeter.
Switches
Switch
Switch Symbol
Also known as the ON/OFF switch. This
switch allows the flow of current only when
it is kept ON.
Relay
Relay Circuit Symbol
Relay is abbreviated as ‘RY’. This device can
easily switch a 230 Volt AC mains circuit. It
has three switching stages called Normally
Open (NO). Normally Closed (NC), and
Common (COM).
Output Devices
Lighting
Lamp
Lamp Circuit Symbol This is used to provide light for the output.
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Indicator
Lamp
Lamp Indicator Circuit Symbol
Used to convert electrical energy into light. The
best example is the warning light on a car
dashboard.
Inductor
Inductor Circuit Symbol
Inductor is used to produce a magnetic field
when a certain current is passed through a coil
of wire. The wire is coiled on a soft iron core.
Have applications in motors, and tank circuits.
Abbreviated as ‘L’.
Motor
Motor Circuit Symbol
This device is used to convert electrical energy
into mechanical energy. Can be used as a
generator as well. Abbreviated as ‘M’.
Generator
Generator Circuit Symbol
This device is used to convert mechanical
energy into electrical energy. Abbreviated as
‘G’.
Bell
Bell Circuit Symbol
Used to produce a sound as the output,
according to the electrical energy produced as
the input.
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5. Assembly and testing of electrical machine
Unit 5.1 – Assembly of electrical machine
Unit 5.2 – Testing
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Unit 5.1: Assembly of electrical machine
Pre-assembly activities
Pre assembly activities includes following activities:
1. Effectively inspecting material before commencement of work
Firstly you have to inspect the material according to the job requirements has to be done.
You have to understand the assembly blueprints, engineering drawings and other specifications
to identify the sequence of activities required to assemble the machine.
Ensure the correct limits, tolerance and fits of equipment components as per the industry norms
and standards.
2. Collecting tools and equipments
Identify tools and equipment required to perform the assembling of components
Collect tools required during the assembling process
Ensure that tools match the desired specifications
Ensure tools and equipment required for assembly are free from physical damage and ready for
operation
Report damaged / defective components of equipment as per the escalation matrix
Ensure the calibration status of all measuring equipment and instruments
Prepare the foundation base as per the job requirements i.e. cleaning using hand files, scraper,
etc
Use braces, jacks, clamps, ropes or bolt straps to hold parts in position
3. Effectively prepare machines and tools
• Ensure and check all tools and equipment required during assembly is ready for operation
• Ensure and check the calibration status of all measuring equipment and instruments
• Remove rough spots from work piece using portable grinder, hand file or scraper
• Check the electrical connections of the equipments.
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Jointing techniques of components
Torque tightening
Principally there are three different "torque components":
• torque to stretch the bolt
• torque to overcome friction in bolt and nut threads
• torque to overcome friction at the nut spot face (bearing contact surface)
Procedure
1. Spanner tight ensuring that 2-3 threads extend above nut
2. Tighten each bolt to one-third of the final required torque.
3. Increase the torque to two-thirds following the pattern shown above.
4. Increase the torque to full torque following the pattern shown above.
5. Perform one final pass on each bolt working clockwise from bolt 1, at the full final torque.
Thread jointing
This method pertains to the application and assembly of products for the sealing of threaded joints. The
procedure is to be used when assembling pipes or other threaded parts, using thread
lockers, retainers or thread sealants.
Procedure
1. Apply the sealing compound to the male threads.
When applying to pipes, start two threads from the
end of the pipe. Apply to the root of 3 or 4 of the
threads.
2. Assemble the joints to the required torque. Do not
over tighten.
3. The assembled parts will be sealed within one hour.
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Motor Installation
All personnel involved with electrical equipment, installation, operation or maintenance should be well-
informed and updated concerning the safety norms and principles that govern the work and,
furthermore, they are advised to heed them.
Before installation please check that:
1. the electric motor is not visibly damaged (whether damaged in transit or during storage).
2. the information on the nameplate corresponds with the features of the electric motor and its
intended use; the power supply voltage matches the mains voltage.
3. the ambient temperature is between -15°C and +40°C.
4. the relative humidity level is 90%.
5. the IP protection rating given on the nameplate is suited to the environment.
Mechanical installation
1. Foundation: The motor base must be level and as far as possible free of vibrations. A concrete
foundation is recommended for motors over 100 HP (75kW). The choice of base will depend upon the
nature of the soil at the place of installation or of the floor capacity in the case of buildings.
2. Types of bases
a) Slide Rails: When motor drive is by pulleys the motor should be mounted on slide rails and the lower
part of the belt should be pulling to avoid belt slippage during operation and also to avoid the belts to
operate sidewise causing damage to bearing shoulders.
The rail nearest the drive pulley is positioned in such a way that the adjusting bolt be between the
motor and the driven machine.
b) Foundation Studs: Very often, particularly when drive is by flexible coupling, motor is anchored
directly to the base with foundation studs. This type of coupling does not allow any thrust over the
bearings and it is of low cost.
Foundation studs should neither be painted nor rusted as both interfere with the adherence of the
concrete, and bring about loosening.
c) Metallic Base: The metallic base is susceptible to distortion if secured to a foundation that is not
completely flat.
When a metallic base is used to adjust the height of the motor shaft end with the machine shaft end,
the latter should be level on the concrete base. After the base has been levelled, foundation, studs
tightened, and the coupling checked, the metal base and the studs are cemented.
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3. Alignment: The electric motor should be accurately aligned with the driven machine, particularly in
cases of direct coupling. An incorrect alignment can cause bearing failure, vibrations and even shaft
rupture.
4. Coupling: Direct coupling is always preferable due to low cost, space economy, no belt slippage and
lower accident risk. In cases of speed ratio drives, it is also common to use a direct coupling with a
reducer (gear box).
Assembly of Pulleys: To assemble pulleys on shaft ends with a keyway and threaded end holes the
pulley should be inserted halfway up the keyway merely by manual pressure.
Electrical installation - Steps
1. Wiring:
Connect the motor to the mains.
Do not connect up or start the motor if the wiring diagram is absent.
Before making the connections, check that the motor's wires are properly tightened down
to the terminal block.
When the motor is connected to the load for proper direction of rotation and started, it should start
quickly and run smoothly. If not, stop the motor immediately and determine the cause. Possible causes
are:
low voltage at the motor,
motor connections are not correct
or the load is too heavy.
Check the motor current after a few minutes of operation and compare the measured current with the
nameplate rating.
2. Grounding:
The power and GND cables must comply with established practice and standards, and be
properly insulated and rated for the current draw.
All motors are equipped for grounding inside the terminal block box and outside on the
motor casing; the GND clamp points are marked with the relevant symbol.
Secure the GND cable to prevent it slackening (use an elastic washer between the terminal
and the bolt) and rotating (use only split cable terminals).
3. Before starting up the motor, check its direction of rotation; if it is required to run in the opposite
direction from the default direction, for three-phase motors simply swap 2 phases; for single-phase
motors. The direction of rotation is clockwise when seen from the drive side.
4. After wiring the unit, refit the terminal block cover with its gasket.
5. For brake motors, check the operation of the brake and its braking torque before starting the motor.
6. Do not touch the motor's housing while it is running as it can reach more than 50°C.
7. Noise: For specific sound power or pressure level information.
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Safety regulations: the electric motor must be installed and operated by qualified personnel who
observe the relevant safety regulations; the safety equipment necessary for the prevention of accidents
during motor set up and operation must also comply with the requirements of applicable safety
regulations.
Motor Maintenance
A well-designed maintenance program for electric motors, when correctly used, can be summed up as:
periodical inspection of insulation levels, temperature rise, wear, bearing lubrication at the occasional
checking of fan air flow.
Cleanliness: Motors should be kept clean, free of dust, debris and oil. Soft brushes or clean cotton rags
should be used for cleaning.
Lubrication: Proper Lubrication extends bearing life. Lubrication Maintenance Includes:
a) Attention to the overall state of the bearings;
b) Cleaning and lubrication;
c) Careful inspection of the bearings.
Bearings should be lubricated to avoid the metallic
contact of the moving parts, and also for protection
against corrosion and wear.
For this reason, lubricants must be renewed and any
lubricant consumed needs replacing from time to
time.
Correct lubrication is important!
Grease must be applied correctly and in sufficient quantity as both insufficient and excessive
greasing are harmful.
Excessive greasing causes overheating brought about by the greater resistance caused on the
rotating parts and, in particular, by the compacting of the lubricant and its eventual loss of
lubricating qualities.
This can cause seepage with the grease penetrating the motor and dripping on the coils or other
motor components.
Stripping of windings: This requires great care to avoid knocking and denting of enclosure joints.
Impregnation: Protect all frame threads by using appropriate bolts, and terminal box support fitting
with a non-adhesive varnish.
Testing: Rotate the shaft by hand while examining for any drag problems on covers or fastening rings.
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Unit 5.2: Testing
Testing Techniques
Visual inspection
A visual test examines bead appearance, width and thickness; defects such as undercut, overlap, cracks,
pits in the surface of product.
This test is simple and inexpensive. Therefore, it is commonly applied to all tools, equipments and
machines.
Destructive tests
Destructive tests aim to examine the mechanical, chemical and metallurgical properties by breaking,
deforming or chemically processing test specimens. Destructive teats further classified into following
tests:
a) Tensile Test:
This test is used for determining the tensile strength, yield point and reduction in area
The piece to be tested is clamped in a tensile testing machine
The load (Force) is applied along the axis
The load (Force) is applied till the specimen is broken
The readings are plotted on a graph
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b) Bend Test:
Bend tests examine the ductility of metals and whether they contain defects or not.
c) Impact Test:
Impact test is conducted to determine the resistance to impact loads or shock loads.
The distance through which the specimen moves after breaking is measured on a scale
The longer the distance ,the less impact resistance the specimen has
d) Hardness test
The hardness test is required to confirm whether or not the metal is hard enough to resist mechanical
wearing, or whether or not the weld is ductile enough to stresses, depending on the usage.
Non-destructive tests
Nondestructive tests can detect defects by utilizing radiation, ultrasonic waves, electricity, magnetism,
or light. Some of the non-destructive tests are:
1. Radiographic test
When an accelerated electron hits a target of heavy metal, the radiation emanates. This radiation is a
kind of electromagnetic wave; and the shorter the wavelength, the stronger its penetrative capacity. A
method to detect defects inside the component utilizing this penetrable capacity is called the X-ray test.
Weld zones can also be examined utilizing the radioactive isotopes that emit γ-rays. These two methods
using X-rays and γ-rays are called the radiographic test.
2. Ultrasonic test (UT)
The ultrasonic test is a detection method which causes an inaudible, short sonic wave of 0.5-15 MHZ
(megahertz) to penetrate the object to be tested. The ultrasonic wave is reflected from an internal
defect or uneven layer.
Raw material inspection
Check manufacturer’s written certification that all material meets appropriate.
Prior to factory seaming, all roll goods will be unwound and visually inspected for contaminants,
defects, undispersed raw materials and edge uniformity.
All defects or impurities will be removed from the roll prior to being fabricated into panels or
the roll will be rejected.
Thickness measurements will be made at the beginning and end of each roll of material.
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Raw material testing:
Visually check or inspect the surface uniformity of the material. Check for dust or any
contaminants.
By using micrometer, measure and inspect the thickness of material as per the job drawing
requirements.
Use tensile testing machine to check the tensile strength of the material.
Machine and equipments testing
Visually check the machine and equipments for any damages.
Use destructive tests to check the physical properties of equipments.
Use non-destructive tests to identify the faults and defects in the machine and equipments.
After testing tag the equipment with its part number or transaction number.
Fill the inspection log sheet for keeping the information in future use.
Tools and measuring instruments testing
Visually check the tools and instruments for any damages.
Use destructive tests to check the physical properties of tolls and instruments.
Manually operate and check the tools are working properly or not.
Check the accuracy of measuring instruments by comparing the zero reading of instruments
with the standard industrial measurement reading.
Fill the inspection log sheet for keeping the information in future use.
Electrical connections testing
Test the electrical connections of the various power operated equipments.
Do the earthing or ground resistance testing of the equipments by using earth testers and
megger.
Check the electrical connections e.g. phase wire, neutral wire and ground wire visually or by
using neon tester and test lamp.
If found any defect in connection wire replace it, otherwise it may give you a severe shock or
damage the equipment.
After completing the operation always switch-off the equipment power, otherwise it can
become risk for serious accidents or hazards.
Fill the inspection log sheet for keeping the information in future use.
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6. Work effectively with others
Unit 6.1 - Effective communication at work place
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Unit 6.1: Effective communication at work place
Communicate with others properly
How you treat people says a lot about you. Each colleague plays an important role in the success of the
organization.
• People like hearing their own names. Learn your co-workers’ names and learn them quickly.
• Don’t assume a person is more or less important because of his/her title. Speak to everyone you
work with or pass in the hallway. Every employee deserves your respect!
• Self-assess: Think about how you treat your supervisor(s), peers, and subordinates. Would the
differences in the relationships, if seen by others, cast you in an unfavorable light? If so, find
where the imbalance exists, and start the process of reworking the relationship dynamic.
• What you share with others about your personal life is your choice, but be careful. Your
openness may have a negative impact. Don't ask others to share their personal lives with you.
This makes many people uncomfortable in the work space.
• Respect other people's personal space. This may be very different than your own.
Sometimes it’s not what you say, but how you say it that counts! Proper communication is equally
important whether your delivery is spoken, written or implied.
Effective communication with colleagues
Here are some ways to communicate better with your colleagues at work:
• Listen actively: Listening actively shows that you’re
interested in what your colleague has to say and that you
respect them. Listen to them closely, orienting your body
towards them, and look at them directly as they speak. While
they’re talking, don’t interrupt them. You’ll only be able to
understand what they’re trying to say if you listen to them
closely and wait for them to finish speaking before you reply.
Then ask questions to clarify any issues you may have. Most
importantly, don’t email or text while someone’s talking to you.
Fitter – Electrical Assembly
Participant Handbook Page 50
• Speak with discretion and talk face to face: Speaking with discretion prevents any
misunderstandings with your colleagues. Face to face communication helps with building trust
and openness, and it enables you to sense and understand someone’s viewpoint and feelings.
• Offer constructive criticism: When giving feedback, leave your personal feelings out of it and
make sure your workmate fully understands what you’re telling them. If someone did a great
job, offer positive reinforcement and also give them improvement tips without being mean or
bossy.
• Build and earn trust: For effective communication to occur, everyone must trust and respect
each other. To build trust with your colleagues, it’s important that you act consistently and with
integrity. To earn their trust, communicate clearly, collaboratively and confidentially with them
while showing them respect. Clear and concise communication will allow your colleagues to
understand and then trust you.
• Get personal but don’t be too casual: Get to know your colleagues better by talking about your
personal lives during breaks or after work. This is also a good way to build trust. However, it’s
important that you don’t get too casual in your conversations, especially in the office, as it might
make the other person uncomfortable.
• Tell them how what you’re communicating is relevant to them: Your communication is only
relevant if it’s related to what the other person wants, needs, fears or desires. Figure out how
what you’ll say or write is relevant to your colleague and then tell them about it. If what you’re
communicating is indeed relevant to them, then it will keep them listening to or reading what
you’re trying to say.
• Keep spoken and written communications short, simple and direct: Don’t expect your
colleague to listen to and read everything that you’re trying to tell them because there’s just not
enough hours in the day. Try to avoid giving them complex explanations and recommendations
with the expectation they will understand everything straight away. It’s best to keep your
communications short, simple and direct.