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Basic Electricity Module: Fundamentals & Applications

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Republic of the Philippines
Department of Education
PUBLIC TECHNICAL-VOCATIONAL
HIGH SCHOOLS
mhar
cueto
Unit of Competency: FUNDAMENTALS OF ELECTRICITY
Module No.:
1
Module Title: BASIC ELECTRICITY
ACKNOWLEDGMENT
Copyright Department of Education 2008
First Published JUNE 2008
This draft was prepared during the Competency-Based Learning Materials
Development Workshop conducted at the Marikina Hotel, Marikina City on
February 18-22, 2008 and finalized on May 23-25, 2008 at the Development
Academy of the Philippines (DAP), Tagaytay City.
This learning instrument was developed by the following personnel:
Technology Teacher:
Mr. Lyndon L. Catequista
Marcelo I. Cabrera Vocational High School
San Aquilino, Roxas, Oriental Mindoro
Contextual Teacher:
Ms. Gina C. delos Santos
A.F.G. Bernardino Memorial Trade School
Lias, Marilao, Bulacan
Facilitators:
Dr. Corazon Echano
TechVoc Task Force
Encoder:
Mr. Lemuel C. Valles
Administrative Officer II
Educational Information Division
Fund: Department of Education
REFERENCES AND FURTHER READING
1. Azares, Efren F. and Recana, Cirilo B. Practical Electricity III; Adriana
Publishing: 1999.
2. Agpaoa, Feleciano. Interior and Exterior Wiring Troubleshooting; National
Bookstore: 1991.
3. Fajardo, Max B. and Fajardo, Leo R. Electrical Layouts and Estimates. 2nd
Edition.
4. Cardenas, Elpidio J. Fundamental and Elements of Electricity.
TABLE OF CONTENTS
Page
How to Use this Module ........................................................................................ i
Introduction ........................................................................................................ ii
Technical Terms ................................................................................................. iii
Learning Outcome 1: Apply relevant electrical theories and principles ………………1
 Learning Experiences/Activities ................................................................. 2
 Information Sheet 1.1 ................................................................................ 3
 Self-Check 1.1 ........................................................................................... 6
 Activity Sheet 1.1 ....................................................................................... 8
Learning Outcome 2: Identify sources of energy …………………………....................10
 Learning Experiences/Activities ............................................................... 11
 Information Sheet 2.1 .............................................................................. 12
 Self-Check 2.1 ......................................................................................... 15
 Activity Sheet 2.1 ..................................................................................... 17
Learning Outcome 3: Splice and joint electrical conductors ……………................. 19
 Learning Experiences/Activities ............................................................... 20
 Information Sheet 3.1 .............................................................................. 21
 Self-Check 3.1 ......................................................................................... 26
 Operation Sheet 3.1 ................................................................................. 27
 Operation Sheet 3.2 ................................................................................. 28
 Job Sheet 3.1 ........................................................................................... 29
 Job Sheet 3.2 ........................................................................................... 31
Learning Outcome 4: Connect electrical circuit …………………………………………..33
 Learning Experiences/Activities ............................................................... 34
 Information Sheet 4.1 .............................................................................. 35
 Self-Check 4.1 ......................................................................................... 37
 Information Sheet 4.2 .............................................................................. 38
 Self-Check 4.2 ......................................................................................... 39
 Activity Sheet 4.1 ..................................................................................... 40
 Activity Sheet 4.2 ..................................................................................... 42
Learning Outcome 5: Decode resistor value………………………………………………..44
 Learning Experiences/Activities ............................................................... 45
 Information Sheet 5.1 .............................................................................. 46
 Self-Check 5.1 ......................................................................................... 52
 Activity Sheet 5.1 ..................................................................................... 53
 Job Sheet 5.1 ........................................................................................... 56
Learning Outcome 6: Identify types of capacitors ………………………………………..57
 Learning Experiences/Activities ............................................................... 58
 Information Sheet 6.1 .............................................................................. 59
 Self-Check 6.1 ......................................................................................... 63
 Activity Sheet 6.1 ..................................................................................... 64
Answer Key 1.1 .................................................................................................. 65
Answer Key 2.1 .................................................................................................. 66
Answer Key 3.1 .................................................................................................. 68
Answer Key 4.1 .................................................................................................. 69
Answer Key 4.2 .................................................................................................. 70
Answer Key 5.1 .................................................................................................. 71
Answer Key 6.1 .................................................................................................. 72
HOW TO USE THIS MODULE
Welcome to the Module “Basic Electricity”. This module contains
training materials and activities for you to complete.
The unit of competency “Fundamentals of Electricity” contains the
knowledge, skills and attitudes required for a Building Wiring Installation
course National Certificate (NC) Level II.
You are required to go through a series of learning activities in order to
complete each of the learning outcomes of the module. In each learning outcome
there are Information Sheets, Job Sheets, Operation Sheets and Activity
Sheets. Do these activities on your own and answer the Self-Check at the end of
each learning activity.
If you have questions, do not hesitate to ask your teacher for assistance.
Recognition of Prior Learning (RPL)
You may already have some or most of the knowledge and skills covered
in this module. If you can demonstrate competence to your teacher in a
particular skill, talk to your teacher so you do not have to undergo the same
training again. If you have a qualification or Certificate of Competency from
previous trainings, show it to him/her. If the skills you acquired are consistent
with and relevant to this module, they become part of the evidence. You can
present these for RPL. If you are not sure about your competence / skills,
discuss this with your teacher.
After completing this module ask your teacher to assess your competence.
Result of your assessment will be recorded in your competency profile. All the
learning activities are designed for you to complete at your own pace.
In this module, you will find the activities for you to complete and relevant
information sheets for each learning outcome. Each learning outcome may have
more than one learning activity.
This module is prepared to help you achieve the required competency in
receiving and relaying information. This will be the source of information that
will enable you to acquire the knowledge and skills in Building Wiring
Installation NC II independently at your own pace or with minimum supervision
or help from your teacher.
i
Program/Course:
BUILDING WIRING INSTALLATION NC II
Unit of Competency:
FUNDAMENTALS OF ELECTICITY
Module Title:
Basic Electricity
INTRODUCTION:
This module contains information and suggested learning activities on the
fundamental and elements of electricity. It includes instruction and procedure
on basic electricity.
This module consists of six (6) learning outcomes. Each learning outcome
contains learning activities supported by instruction sheets. Before you perform
the instruction sheets, read the information sheets and answer the self-check
and activities provided to ascertain to yourself and your teacher. He /she will
check if you have acquired the knowledge necessary to perform the skill portion
of the particular learning outcome.
Upon completing this module, report to your teacher for assessment to
check your achievement of knowledge and skills requirements of this module. If
you pass the assessment, you will be given a certificate of completion.
SUMMARY OF LEARNING OUTCOMES:
Upon completion of the module, the students shall be able to:
LO 1 Apply relevant electrical theories and principles
LO 2 Identify sources of electricity
LO 3 Splice and joint electrical conductor
LO 4 Connect electrical circuit
LO 5 Decode resistor value
LO 6 Identify types of capacitor
ASSESSMENT CRITERIA:
Refer to assessment criteria of learning outcomes # 1-4 of this module.
PREREQUISITE:
None
ii
TECHNICAL TERMS
Ampere is the standard unit used in measuring the strength of an electric
current.
Atom is the smallest part in which an element can be divided.
Current is the flow or the rate of the flow of electric force in a conductor.
Electricity is a form of energy generated by friction, induction or chemical
change.
Electron has magnetic, chemical and radiant effect. It is also the negatively
charged particle of an atom.
Joint is process whereby one length of wire is connected or tapped together.
Neutron is the particle of an atom which is not electrically charged.
Nick is a slight cut on wire.
Ohms is the unit of electrical resistance.
Power is the product of voltage and current.
Proton is the positively charged particle of an atom.
Resistance is the opposition to the flow of current.
Skinning /Stripping is a process of removing wire insulation.
Solder is a fusible metal or alloy used for joining metallic surfaces or margins
Splice is termed “straight joint”; a series connection of a pair of conductor or
cables.
Taping is the method of insulating conductor joints.
Volt is the unit of measure for voltage.
Voltage is the electrical pressure that causes the electrons to move through a
conductor.
Wire stripper is a tool used to cut and remove wire insulation from wire.
iii
Program/Course:
BUILDING WIRING INSTALLATION NC II
Unit of Competency:
FUNDAMENTALS OF ELECTICITY
Module Title:
Basic Electricity
Learning Outcome 1: Apply relevant electrical theories and principles
Assessment Criteria:
1. The principles and theories of electron are applied when dealing with
electrical works.
2. The atomic structure is illustrated.
References:
1. Azares, Efren F. and Recana, Cirilo B. Practical Electricity III; Adriana
Publishing: 1999.
2. Agpaoa, Feleciano. Interior and Exterior Wiring Troubleshooting; National
Bookstore: 1991.
3. Fajardo, Max B. and Fajardo, Leo R. Electrical Layouts and Estimates. 2nd
Edition.
4. Cardenas, Elpidio J. Fundamental and Elements of Electricity.
1
LEARNING EXPERIENCES/ACTIVITIES
Learning Outcome 1: Apply relevant electrical theories and principles
Learning Activities
Special Instructions
1. Read Information Sheet 1.1 about
the relevant electrical theories and
principles.
2. Perform the Activity Sheet 1.1 on a
separate sheet of paper.
3. Answer Self-Check 1.1.
2
INFORMATION SHEET 1.1
ELECTRON THEORY
INTRODUCTION
Electricity is a property of the basic particle of matter which, like an atom,
consists of proton, electron and neutron. The electron is the negatively charged
particle of an atom which is sometimes referred to as the negatively charge of
electricity. On the other hand, the proton is the positively charged particle of an
atom which is sometimes referred to as the positively charge of electricity that
weighs about 1850 times as much as the electron. The neutron is the particle
which is not electrically charged and weighs slightly more than proton.
Theory:
1. That all matters are made up of molecules
2. That molecules are made up of atoms
3. That the atoms contain neutron, electrons and protons
5. That the neutron is neutral, hence, neither positively nor negatively
charged.
6. That the electron of an atom of any substance could be transferred to
another atom
The electron theory
The electron theory states that all matter is made up of electricity. Matter is
anything which has weight, occupies space is made up of molecules, of which
millions of different kinds. The molecules in turn, are made up of atoms of
which are the smallest units of the several elements and of a limited number.
All atoms believed to be composed of electrons, which are minute particle of
negative electricity normally held in place in each atom by positively charged
particles called nucleus. Thus, the electron, which are interlocked in the atoms,
are constantly revealing at great speeds in orbits around positive nuclei. In a
normal atom, the amount of negative electricity of the electrons is exactly
neutralized by an equal amount of opposite or positive electricity of the nucleus.
Thus, a normal atom exhibits no external sign of electrification.
3
Structure of an atom
All atoms consist of two basic parts: a
body at the center of the atom called the
nucleus, orbiting around the nucleus.
Atoms may have more than one orbiting
electron, but each atom contains only one
nucleus.
The attraction between the nucleus and
the electron is called electrostatic force,
which holds the electron in an orbit.
Bodies that attract each other in this
special electrostatic way are described as
charged object. The electron carries the
negative charge (-), while the nucleus
carries the positive charge (+).
Electron
Nucleus
Electron
Electron force
holds the
electron orbit.
Nucleus
Electron
The positive charge of the nucleus is
due to the particles called protons, which
are found inside the nucleus and have a
positive charge equal to the electron’s
negative charge.
Nucleus
Proton
The structure of neutrons in the atoms showing the position of its proton,
electron, nucleus and neutron is shown below.
4
First Law of Electrostatics
The protons and electrons attract each other inside the atom. It has been
known that by nature, unlike charges (like the positive protons and negative
electrons) attract each other while like charges repel each other, meaning
electrons and protons repel each other’s protons.
Like charges repel each other
Unlike charges attract each other
5
SELF-CHECK 1.1
I. Directions: Read the following sentences carefully. Write the letter of your
answer on a separate sheet.
1. The same electrical charge ___________ each other.
A. attracts
B. repel
C. destroy
D. neutralize
2. It is neither positively nor negatively charge.
A. electron in motion
B. electrostatic force
C. neutron
D. atom
3. It is the equal number of electron and proton in an atom.
A. positive
B. negative
C. neutral
D. none of the above
4. The electron theory states that all matter is made of ________________.
A. neutron
B. atom
C. electron
D. molecules
5. It is the smallest particle of molecule.
A. ion
B. proton
C. electron
D. atom
II. Directions: Choose the correct answer in the box below. Write your answer
on a separate sheet of paper.
1. What is the nature of matter?
2. How will you prove that electricity is a matter?
3. What is molecule made up?
4. What is the neutral particle of an atom?
neutron
atom
molecule
occupies space
has weight
6
III. Directions: Read each question carefully. Choose the letter of the correct
answer in the box below. Write your answer on a separate
answer sheet.
1. What is found at the center body of an atom?
2. What do you call the attraction between the nucleus and the electron?
3. What do you call the positively charged particle of an atom?
4. What do you call the negatively charged particle of an atom?
5. What particle of an atom is not electrically charged?
Electron
neutron
proton
nucleus
electrostatic force
proton
7
ACTIVITY SHEET 1.1
Supplies and Materials






Comb
Small pieces of paper
Dry woolen cloth
Ballon
Wall
Dry fine sand
Working Drawing
Procedure
1. Bring your comb near the small pieces of paper. What happened?
2. Rub your comb briskly with a dry woolen cloth.
3. Bring the comb towards some tiny pieces of paper. What happened to the tiny
pieces of paper? Compare your observation with the second step.
4. Rub the inflated balloon with the woolen cloth.
5. Put the balloon against the wall. Why did the balloon stick on the wall? Do you
think the same will happen without rubbing the balloon?
6. Rub the balloon with the woolen cloth again.
7. Hold the balloon over very dry fine sand. What happened to the sand when you
brought the balloon near it? What kind of electricity was produced when you
rubbed two materials of different kind?
8
Observation
Steps
Remarks / Comments
First Step
Second Step
Third Step
Forth step
Fifth step
Sixth step
Seventh step
9
Program/Course:
BUILDING WIRING INSTALLATION NC II
Unit of Competency:
FUNDAMENTALS OF ELECTRICITY
Module Title:
Basic Electricity
Learning Outcome 2: Identify sources of electricity
Assessment Criteria:
1. The sources of electricity are identified.
2. The principles and operations of each source are explained.
References:
1. Azares, Efren F. and Recana, Cirilo B. Practical Electricity III; Adriana
Publishing: 1999.
2. Agpaoa, Feleciano. Interior and Exterior Wiring Troubleshooting; National
Bookstore: 1991.
3. Fajardo, Max B. and Fajardo, Leo R. Electrical Layouts and Estimates. 2nd
Edition.
4. Cardenas, Elpidio J. Fundamental and Elements of Electricity; National
Bookstore: 1989.
10
LEARNING EXPERIENCES/ACTIVITIES
Learning Outcome 2: Identify sources of electricity
Learning Activities
Special Instructions
1. Read Information Sheet 2.1
about sources of electricity.
2. Answer Self-Check 2.1.
3. Read Information Sheet 2.2
about the types of mechanical
power plants.
4. Answer Self-Check 2.2.
5. Answer Activity Sheet 2.1.
11
INFORMATION SHEET 2.1
SOURCES OF ELECTRICITY
1. Friction
- is a static electricity which is generated by rubbing two
materials.
2. Chemical action
- a great deal of the world’s electricity is produced by
batteries.
These devices generate a different or
potential means of chemical action.
3. Heat action
- two dissolution metals bonded together in a junction
when heated, exhibits a difference of potential. Such
bond is called thermocouple. The trip of an iron wire,
for example, may be welded to that of a copper wire.
When, this junction is heated, the iron wire shows a
positive charge and the copper wire has a negative
charge. Electricity generated by heat action is called
Thermoelectric.
4. Light action
- photo cells are semi-conduction devices which convert
light electrical energy directly into electrical energy.
Either sunlight or artificial illumination may be
employed. This action is due to the ability of lights
energy to free electrons from the atoms of the semiconductor material.
This process is called Photoelectricity.
5. Pressure
- is a difference of potential appears across the face of
certain crystal such as quarts, when they are squeezed
or stretched. This is called Prezo-electricity.
6. Mechanical action - all electricity in large useful amount is at present
produced by rotating machines working with the use of
magnets. These machines, known as generator, are
turned by water power, gas engines or steam engines
and sometimes by electric motor.
There are many different types of mechanical power plants to produce
electrical energy.
Hydropower
is
energy
obtained from flowing water.
Energy in water can be
harnessed and used in the foot
motive energy or temperature
differences. The most common
application is the dam.
12
Power produced by the fall of water from a higher to a lower level, and extracted
by means of waterwheels or hydraulic turbines. Hydro-power is a natural
resource, available wherever a sufficient volume of steady water flow exists.
Nuclear Power is the
method in which steam is
produced by heating water
through a process called
nuclear fission. In a nuclear
power
plant,
a
reactor
contains a core of nuclear fuel,
primary enriched uranium.
When atoms of uranium fuel
are hit by neutrons they
fission (split), releasing heat
neutrons.
Nuclear power is electrical power produced from energy released by controlled
fission or fusion of atomic nuclei in a nuclear reaction. Mass is converted into
energy, and the amount of released energy greatly exceeds that from chemical
processes such as combustion.
Solar Power is the power
derived from the energy of the
sun. A radiant energy produced
in the Sun as a result of nuclear
fusion
reactions.
It
is
transmitted to the earth through
space
by
electromagnetic
radiation in quanta of energy
called photons, which interact
with the earth’s atmosphere and surface.
Wind Power is the kinetic
energy of wind, or the
extraction of this energy by
wind
turbines.
Windmill
machine that converts wind
into useful energy. This energy
is derived from the force of
wind acting on oblique blades
or sails that radiate from a
shaft. The turning shaft may
be connected to machinery
used to perform such work as
milling grain, pumping water, or generating electricity. When the shaft is
connected to a load, such as a pump, the device is typically called a windmill.
When it is used to generate electricity, it is known as a wind turbine generator.
13
Fossil Fuel Power Plant (FFPP) – (also
known as steam electric power plant in the
US, thermal power plant in Asia, or power
station in UK). The most common source of
energy is fossil fuel. Fossil fuels include coal,
oil, and natural gas.
Fossil fuel is formed from the remains of
plant and animals which live thousands of
years ago. The burning of those fossil fuel
provides energy which can be used to
generate electricity.
z
Geothermal power comes from heat energy
buried beneath the surface of the earth. In some
areas of the country, enough heat rises close to the
surface of the earth to heat underground water into
steam, which can be tapped for use in steamturbine plants.
Geothermal Power is the energy extracted
from the heat generated by natural concentrations
of hot water and steam in the earth’s interior. It can
be used in electric power generation and direct heat applications such as space
heating and industrial drying processes.
Tides is another kind of energy that involves water
is tidal energy. Ocean tides can be used to turn
turbines to generate electricity. For this to be possible,
a dam must be built across the month of a bay. Water
then trapped behind the dam at the high tide. At the
low tide, the water is allowed to run out through the
dam and used to turn electrical generator.
14
SELF-CHECK 2.1
I. Directions: Match Column A with Column B. Write your answer on a separate
answer sheet.
A
1. Friction
2. Chemical action
3. Heat action
4. Light action
5. Prezo-electricity
6. Mechanical
action
7. Magnet
8. Magnetic
induction
9. Thermoelectricity
10. Pressure
B
a. two metals bounded together in junction by
thermocouple process
b. electricity produced by rotating machine
c. electricity generated by rubbing two
materials
d. electricity produced by batteries
e. a process of photo-electricity
f. an action of squeezing or stretching crystal
g. imaginary lines along which the attraction
or repulsion of a magnet act
h. a body having the property of polarity and
of attraction and repulsion found in the
nature.
i. Potential difference appears across the
faces of quartz when squeezed
j. electricity generated by heat action.
II. Directions: From the given words below, choose the correct word that would
complete the sentence. Write your answer on a separate sheet of paper.
fossils fuels
nuclear energy
geothermal
biomass energy
tidal energy
solar energy
1. It is the energy that comes from the sun.
2. It is the energy that involves water.
3. It is the energy that comes from the inner
core of the earth.
4. It is the result from the splitting or fission of
atomic nuclei.
5. It is the energy formed from the remains of
plant and animals which live thousands of
years ago.
15
III. Directions: Choose the letter of the correct answer. Write your answer on
your notebook.
1. The following are the sources of energy except:
A. sun
B. nuclear reaction
C. fossil fuel
D. transformer
2. Which is a nonrenewable source of energy?
A. fossil fuel
B. solar energy
C. tidal energy
D. wind energy
3. Which is non-conventional source of energy?
A. fossil fuel B. gasoline
C. solar energy D. hydroelectric power
4. The Makiling-Banahaw Plant in Laguna is an example of _______.
A. nuclear power plant
B. geothermal plant
C. hydroelectric power plant
D. fossil fuel- fired plant
5. What source of energy is shown in the picture?
A. fossil fuel B. solar energy C. wind energy
D. tidal energy
16
ACTIVITY SHEET 2.1
On the pictures below, trace and explain the process of the different power
plants on how they produce electricity.
Nuclear power
Hydroelectric power
17
Geothermal power
Solar power
18
Program/Course:
BUILDING WIRING INSTALLATION NC II
Unit of Competency:
FUNDAMENTALS OF ELECTICITY
Module Title:
Basic Electricity
Learning Outcome 3: Splice and joint electrical conductors
Assessment Criteria:
1. Different types of splices and joints are identified according to their us
2. Techniques in skinning electrical wire are demonstrated.
3. Methods of splicing and joining electrical wires are performed according to
prescribed procedure.
4. Safety procedure in splicing and joining electrical wires is observed.
References:
1. Azares, Efren F. and Recana, Cirilo B. Practical Electricity III; Adriana
Publishing: 1999.
2. Agpaoa, Feleciano. Interior and Exterior Wiring Troubleshooting; National
Bookstore: 1991.
3. Fajardo, Max B. and Fajardo, Leo R. Electrical Layouts and Estimates. 2nd
Edition.
4. Cardenas, Elpidio J. Fundamental and Elements of Electricity; National
Bookstore: 1989.
19
LEARNING EXPERIENCES/ACTIVITIES
Learning Outcome 3: Splice and joint electrical conductors
Learning Activities
1. Read the attached Information
Sheet 3.1 about splices and joints.
2. Answer Self-Check 3.1.
3. Perform Operation Sheet 3.1 on
how to remove the insulation.
Special Instructions

Ask the assistance of teacher if
needed.

Provide a separate sheet of paper
for your answer sheet.

Follow procedure carefully.
4. Read the Job Sheet 3.1 on how to
remove the insulation.
20
INFORMATION SHEET 3.1
SPLICES AND JOINTS
Method of Skinning Electrical Wire
Removing the insulation in preparing the insulated conductors for making
joints or splices, the insulation must first be removed from each conductor a
proper distance depending upon the type of joint or splice to be made.
This process is called skinning or stripping.
Cleaning the Conductor
After removing the insulation, the wires must be thoroughly cleaned to
ensure good electric contact between the ends of the wires and so that the
solder will adhere properly. The wire may be cleaned by scraping.
Different electrical wires, splices and joints
Different Electrical Wires Splices and Joints
Rat tail joints is used to join conductors in
outlet boxes or when fixture leads are connected
through conductors. The joints are made by
skinning about 2 inches, the end of the conductor
is to be joined. Then twist the bare conductors
about six times.
21
Western Union Short- tie splice - To
make the splice, the wire are first skinned for
about 3 inches at the ends. They are then
placed in crossed position about 1 inch from
the insulation. Four or five short turns are
then wrapped on each side of the longest
twist, and the free ends cut off and squeezed
down closed to the straight position of the
wire so that they will not extend over the
surface of the short turns and permit the sharp to cut through the tape with
the splice to be wrapped.
Western Union Long –Tie Splice- used
extensively for outside wiring and is quite
similar to the short tie splice. It is also being
used for interior wiring. The difference is that
a number of long twist are made before
wrapping the end turns. This is done so to
withstand greater stress of pressure on the
wire. The wire for this splice are bared about
4 ½ inches. They are then placed in the form
of an X at a point midway between the insulation and the end of the base wire.
Five or six long twists are then made and each side those turns are wrapped.
Britannia Splice- It is used in interior
wiring where solid wires of No. 6 AWG
gauge or larger sizes are to be joined and
where large wire connectors or pliers are
not at hand. The two wires are based for
about 4 inches in a No. 6 wire. About ½
inch of the extreme end of each beat to
almost a right angle to the straight portion
of the conductor. A wrapping wire is made of No. 18 bare wire copper is then
cut to about 6 ft. in length and prepared by cleaning and bending in half. The
large conductor is then laid together, one bent end pointing upward and the
other downward. The center of the wrapping wire is then brought to the center
of the conductor, one half of which is wrapped in one direction and other
remaining half in the other as far as the best portion. The free ends are then
forced through the grooves from one ends to the other end of the other of the
large single conductors. The best ends are then cut off close to the joint.
22
Scarfed splice- used only on a large
solid wire where there is an objection to
the bulkiness of the Western Union or
Britannia splice. The wires are bared for
about 3 inches, when a No. 6 wire is used.
The bared wire is then filed to a
wedge shape starting about ½ inch from
the insulations. A piece of No. 18 bare
copper wire is cut to about 5 ft. in length and prepared by cleaning and
bending in haft.
The two file sides of the conductors are then laid together and wrapping
wire wound around them, as similarly done in Britannia Splice. The wrapping
is completed by winding about six and seven turns of the free ends around the
unfilled portion of the conductor.
Multiple wrapped cable splice - is used more
extensively on small strand wires and cables
because these stands are more pliable and may
be wound together without much difficulty. Large
strands are rigid and require considerable time in
making such a splice. To make the splice, the
ends of the conductors are skinned at the
distance of about 6 inches. The strands are
cleaned and spread about apart. Next, the strands are cut about 3 inches from
the insulation to right angle with the conductor. The strands of both
conductors are then laced together, one group of strands wounds in the
opposite direction. Care should be done that all strands in each group are
wrapped simultaneously and parallel to one another.
Plain tap or Tee Joints- is used to
a great extent joining a tap or other
conductor to a through conductor, as
for example, a branch or main circuit.
To make the joint, skin the tap wire
about 2 inches and the main wire
about 1 inch. Next, the wires are
crossed intersecting about ¼ inch from the insulation of the tap wire and the
main wire. A hook or sharp bend is then made in the tap and about five or six
turns wound around the main wire. The joint is soldered and tape. Care must
be taken that the solder flows and sticks through all the crevices and that the
tape covers all part of the conductors, beginning and ending on the original
insulation.
23
Knotted or loop, tap joint- It is
very strong joint and will not untwist
even enough strain is placed upon it. It
is occasionally used in practice,
particularly for temporary lighting
systems, where time is not taken to
solder joints. To make the join using
No. 14 AWG wire, the tap wire is skinned about 3 inches and is then placed
over the insulation of the tap and main wire. The tap wire is bent and hooked
over the main wire and brought forward and bent over itself. Lastly, the
remaining portion is wound into four or five short turns around the main wire.
Wrapped Tap, Tee Joint – It is used on large
solid conductors where is difficult to wrap the
heavy tap wire around the main wire. When a
No. 6 AGW wire is used, both the main wire and
the tap wire are skinned about 4 inches. The tap
wire is bent into an L shape about ½ inches
from the insulation so that it will rest along the
side of the main wire. A wrapping wire is then
prepared using size No. 18 bare conductors terminating beyond the bent of tap
wire and up to the installation of the main conductor.
Ordinary Cable Tap or Tee JointIt is used where large stranded wire or
cables are tapped to a through
conductor. To make the joint, the
main strands should be scraped
through with a knife blade or
sandpaper. The tap wire of similar wire size cable should be skinned about 6
inches distance and the strands separated or fanned each strands of the tap
into the shape. The main cable is placed into this V-shaped space and forced
down to within 1 inch from the insulation of the tap conductor. One group of
tap wire is then wound around the main conductor, each strands should be
placed parallel to the other, and all wrapped at the same time and in one
direction. The other group is wound in similar manner but in the opposite
direction.
Split Cable Tap or Tee Joint- It is
used where stranded cables or wire
are tapped to a through conductor.
This joint is stronger than the
ordinary cable tap and will not
unwrap even though a strain is
placed upon it prior soldering. To
24
make this joint, the main wire is skinned a distance of 5 inches No. 14 AWG
wire size is used and the strands thoroughly scraped as for the ordinary cable
tap. The strands are next divided in half by forcing the screw driver through
the center of the bared portion of the main wire. The tap wire is prepared by
skinning it about 6 inches, scraping each strand until thoroughly cleaned and
fanning out the strands so that they can be pushed around the space in the
main wire. A space about 1 ½ inch should be left between the main wire and
the insulation of the tap wire. In completing the joint, one group is wound
around the main conductor, in one direction, and the second group is wound
in the opposite direction.
The Through Fixture Joint- It is
used where fixtures are connected to
branch wires at an intermediate
point. In making this joint, the end of
one conductor is skinned about 2
inches and the other about 4 inches.
At a point ¼ inches away from the
insulation of the longer wire, three or
four long twists are made similar to the rat-tail joint. The long bared portion of
the long wire is bent over parallel with the free ends. Both free ends are then
place alongside each other wrapped together around the straight bared portion.
Safety procedure in splicing and joining wire
Before the splice is made, the insulation is first removed on both ends with
the use of an electrician’s knife or diagonal pliers. An electrician should be very
careful in removing wire insulation in order that the wire will not be nicked by
the knife or pliers to prevent breaking. However, a specially designed tool to
avoid nicks is called automatic wire stripper. The function of the tool is to cut
the wire insulation and remove it automatically by inserting the wire
corresponding to the size of hole in the wire stripper. After removing the
insulation, the end of the wire is twisted firmly. When the joint has been made,
the correct practice is to solder it to prevent loose contact and to have a
continuous flow of electricity. The splice and joint are then covered properly
with an electrical tape in order to prevent short circuit.
25
SELF-CHECK 3.1
I. Direction: Label the following splices and joints. Write your answer on a
separate answer sheet.
II. Direction: Write the letter of the correct answer o your notebook.
1. It is the method of removing insulation from electrical conductor.
A. Pulling
B. Grabbing
C. Skinning
D. Gripping
2. What should be done to an insulator from conductor before splicing
or joining the wire?
A. Pull
B. Remove
C. Grab
D. Grip
3. What should be the next procedure after removing an insulator from
conductor for soldering a wire?
A. Clean
B. Twist
C. Rub
D. Scrub
26
OPERATION SHEET 3.1
REMOVING THE INSULATION
Materials

Wire conductor
- stranded # 14 or 12 (2m)
- solid # 14 or 12 (2m)
Tools and Equipment



Side cutting pliers
Wire stripper
Personal protective equipment
- gloves
Procedure
1. Prepare the necessary tools, materials and equipment.
2. Wear the appropriate PPE.
3. Removing insulation of wire
Procedure:

Using a wire stripper:
a. Assuming the proper length of insulation to be removed, place the wire
end at the jaw of the wire stripper.
b. Grip the handle with minimum pressure.
c. Pull the wire or the stripper side ward until such time the wire and the
insulator are separated.

Using side cutting pliers
a. Place the wire to be stripped between the handle grips close behind the
gutter/pliers hidge.
b. Squeeze the insulator enough to soften it and break down.
4. Perform good housekeeping.
Assessment Criteria
Accuracy of Skinning
Measurement of insulation to be removed
Use of Tools
Use of PPE
Speed
Housekeeping
TOTAL
5 pts.
4 pts.
3 pts.
3 pts.
3 pts.
2 pts.
20 pts.
27
28
OPERATION SHEET 3.2
SPLICE AND JOINT THE WIRE
Materials

Wire conductor
- stranded # 14 or 12 (2m)
- solid # 14 or 12 (2m)
Tools and Equipment



Side cutting pliers
Long nose
Personal protective equipment
- gloves
Procedure
1. Prepare the necessary tools, materials and equipment.
2. Wear appropriate PPE.
3. Skin the electrical wire to be spliced and joined, following the procedure on
skinning the electrical wire. (Note: Check the wire if there is a nick. Should be
very careful in removing wire insulation in order that the wire will not be
nicked by the knife or pliers to prevent breaking)
4. Splice and joint the following;
- rat tail joint
- western union short tie
- wrapped tap joint
(Note: Follow the procedure in joining and splicing wire. Refer to information
sheet 2)
5. Observe house keeping.
Assessment Criteria
Accuracy of Skinning
Measurement of insulation to be removed
Use of Tools
Use of PPE
Speed
Housekeeping
5 pts.
4 pts.
3 pts.
3 pts.
3 pts.
2 pts.
29
JOB SHEET 3.1
REMOVING THE INSULATION
Materials

Wire conductor
- stranded # 14 or 12 (2m)
- solid # 14 or 12 (2m)
Tools and Equipment



Side cutting pliers
Wire stripper
Personal protective equipment
- gloves
Procedures
1. Using a wire stripper:
a. Assuming the proper length of insulation to be removed, place the wire
end at the jaw of the wire stripper.
b. Grip the handle with minimum pressure.
c. Pull the wire or the stripper side ward until such time the wire and the
insulator are separated.
2. Using side cutting pliers.
a. Place the wire to be stripped between the handle grips close behind the
gutter/plier hidge.
b. Squeeze the insulator enough to soften it and break down.
- Check the wire if there is a nick. (Note: Nick will cause the wire to
break easily.
3. Cleaning the wire.
- Scrape the wire.
4. Perform good housekeeping.
30
Evaluation:
The students will be evaluated based on the following:
SKINNING
No nick of wire
Cleaning of wire
WORKMANSHIP
 Execution of using tool
 Cutting
SPEED
 Before allotted time
 Within allotted time
 After allotted time
20 pts.
10
10
10 pts.
5
5
10 pts.
5
3
2
SAFETY
 Use appropriate PPE
 Use PPE but not appropriate
 No PPE
5 pts.
3
2
0
USE OF TOOLS
 Use tool properly all the time
 Use tools properly most of the time
 Use tools properly sometime
 Improper use of tools
5 pts.
2
2
1
0
50 pts.
TOTAL
31
JOB SHEET 3.2
SPLICE AND JOINT THE WIRE
Materials

Wire conductor
- stranded # 14 or 12 (2m)
- solid # 14 or 12 (2m)
Tools and Equipment



Side cutting pliers
Long nose
Personal protective equipment
- gloves
Procedure
1. Prepare the necessary tools, materials and equipment.
2. Wear appropriate PPE.
3. Skin the electrical wire to be spliced and joined, following the procedure on
skinning the electrical wire. (Note: Check the wire if there is a nick. Should be
very careful in removing wire insulation in order that the wire will not be
nicked by the knife or pliers to prevent breaking)
4. Splice and joint the wire.
5. Do 10 types of wire splices and joints. Follow procedure on the information
sheet.
Assessment Criteria
PROPER SPLICE AND JOINT OF WIRE
Procedure follow
Firmness of twisted or wound wire
WORKMANSHIP
 Execution of using tool
 Cutting
SPEED
 Before allotted time
 Within allotted time
 After allotted time
20 pts
10
.
10
10
pts.
5
5
10 pts.
5
3
2
32
SAFETY
 Use appropriate PPE
 Use PPE but not appropriate
 No PPE
5 pts.
3
2
0
USE OF TOOLS
 Use tool properly all the time
 Use tools properly most of the time
 Use tools properly sometime
 Improper use of tools
2
2
1
0
5 pts.
TOTAL
100%
33
Program/Course:
BUILDING WIRING INSTALLATION NC II
Unit of Competency:
FUNDAMENTALS OF ELECTRICITY
Module Title:
Basic Electricity
Learning Outcome 4: Connect electrical circuit
Assessment Criteria:
1. Kinds of electric circuit of circuit are identified.
2. Value of voltage, current and resistance are computed.
3. Series and parallel circuit connection is demonstrated in accordance with
standard procedure.
References:
1. Magalindan, Fe S., Ph. D., De Guzman, Dionisia G., Ph. D. de la Rosa,
Juanito, and Asprer, Fe F., Technology and Home Economics. 1994
34
LEARNING EXPERIENCES/ACTIVITIES
Learning Outcome 4: Connect electrical circuit
Learning Activities
Special Instructions
1. Read Information Sheet 4.1
about parts and kinds of circuit.

Try to answer self-check without
looking at the information sheet.
4. Answer Self-Check 4.2.

Use a separate sheet of paper as
your answer sheet.
5. Perform Activity Sheet 4.1 on
Bulb in Series.

Follow the procedures carefully.
2. Answer Self-Check 4.1.
3. Read Information Sheet 4. 2
about Ohm’s Law and Power
Law.
6. Perform Activity Sheet 4.2 on
Bulb in Parallel.
35
UJINFORMATION SHEET 4.1
Parts of a Complete Circuit
In order that electricity can be better understood by the student, they should
know the different parts or requirements of a complete circuit. First, the
electrical circuit should have a source of power where the electric current starts
to flow. The power source can be a generator, storage cell one or more cells.
Second, a path such as electrical wires are needed in order that electricity from
the source can be transmitted. Third, there should be a current- consuming
device or appliance that will consume or use electricity. And lastly, a control or
switch that will cut off the flow of current, when the appliance will not be in use.
All the requirements mentioned are important in order to have complete
electrical circuit. The absence of one will not make a complete electric circuit.
Electrical path
source of power
current consuming device
Switch
Kinds of circuit
1. Series Circuit. In a series circuit, many bulbs are wired one after the other,
so that when one of the bulb is busted, all will not light up. The reason is
that the current cannot pass through the bulb because of the filament is cut.
So there is no continuity for current in order to go back to the power source.
In a series connection, electricity flows through each electrical device. You
have to observe that the two bulbs connected in series would light more
brightly than if there were three bulbs in the circuit. The brightness of the
light depends on the amount flowing in each device.
36
Things to remember in the series circuit:



The total resistance in the circuit is the sum of all individual
resistances.
The current throughout the circuit is the same.
The total voltage in the circuit is equal to the sum of the individual
voltages.
2. Parallel Circuit- This is the circuit whereby two or more bulbs are wired with
each bulb having its own circuit. This means that if one is busted, the other
bulb will still light up because current passes separately in each circuit. In a
parallel circuit, the electric current flows and only a part of the total current
in the circuit goes through each bulb. Each bulb has a circuit of its own with
the battery so the electric current flowing through each bulb moves in a
different path in the circuit.
Things to remember in the parallel circuit:



The voltage is the same in all the circuits.
The total current is the sum of all the current in each circuit.
The total resistance is the sum of all resistances in each circuit.
37
SELF-CHECK 4.1
I. Directions: Match Column A with Column B. Write your answer on a separate
answer sheet.
A
1. Switch
2. Source of power
3. Conductor
4. Load
5. Series circuit
connection
6. Parallel circuit
connection
II.
B
a. current cannot pass through the bulb when
the other filament of the bulb is cut
b. caused the load to light up
c. consumes power
d. electrical path
e. bulb has its own circuit
f. control the circuit
Directions: Tell whether the following ideas is a series or parallel circuit.
Write S if the answer is series and P if it is parallel on a
separate sheet of paper.
1. The total current is the sum of all the current in each circuit.
2. The current throughout the circuit is the same.
3. The voltage is the same in all the circuits.
4. The total resistance in the circuit is the sum of all individual
resistances.
5. The total voltage in the circuit is equal to the sum of the individual
voltages.
38
INFORMATION SHEET 4.2
Ohm’s Law and Power Law
If we are going to study the meaning of electricity deeper, there are three
essential elements involved. These are voltage, current and resistance. George
Simon Ohm, a German scientist, discovered in 1826 the relations among them.
The discovery led to one of the major laws in electricity called Ohm’s Law. Each
of the elements has its own unit of measurement, volt for voltage, ampere for
current, ohm for resistance. Volt is named after Alessandro Volta, a physicist
whose invention made volt as an electrical pressure needed in allowing one
ampere of current pass through resistance of one ohm. Another inventor, named
Andre Marie Ampere, a physicist and Mathematician, whose one ampere of
current is the rate of flow of charge passing in a wire conductor that is equal to
one coulomb per second. Electric power is measured in watts, abbreviated W as
a unit. This unit is named after James Watt, a Scotch inventor. It is equal to the
product of the voltage multiplied by the current. The total power of a circuit is
obtained by multiplying the total current by the voltage.
Summary of the Ohm’s Law and Power Law
VOLTAGE
CURRENT
RESISTANCE
POWER
Unit of measure
Volt
Ampere
Ohms
Watt
Symbol
E or V
I
R or Ω
W
Formula
E= I x R
I=E/R
R=E/R
P=ExI
39
SELF-CHECK 4.2
Direction: Find the missing quantity for each of the circuits below.
1.
5Ω
I=2A
V=?
I=2A
2.
R=?
20V
3.
R=5Ω
I=?
10V
I=500A
4.
R=?
100V
5.
6.
R=10Ω
I=0.4A
V=?
25 Ω
I=?
50V
7. An electric heater is rated at 100V and has a hot resistance of 30
ohms. What current will flow through it?
8. An ammeter shows a bulb is using 4 amperes from a 120V source.
What is the resistance?
9. An electric appliance with a resistance of 60 ohms must draw 5A to
operate correctly. What is the correct voltage to use?
10. How much power is consumed by the machine having a current flow
of 6 ampere supplied by a 220 volt line?
40
ACTIVITY SHEET 4.1
BULB IN SERIES
Supplies and Materials





2 pieces 1.5 batteries
2 pieces bulb
1 meter wire
3 pieces socket
1 piece switch
Tool

Pliers
Working Drawing
Procedure
1. Construct an electrical circuit and connect two bulbs in series.
circuit and observe the brightness of the light.
Close the
2. Add one more bulb in the set up. Describe the change in the brightness of
the bulb. In which setup do the bulbs shine more brightly?
3. Unscrew one of the bulbs and close the circuit. Observe what happens.
41
4. Trace the flow of the electric current. How are the bulbs arranged in a series
circuit?
Observation
Steps
First Step
Second Step
Third Step
Forth step
Remarks / Comments
42
ACTIVITY SHEET 4.2
BULB IN PARALLEL
Supplies and Materials





2 pieces 1.5 batteries
2 pieces bulb
1 meter wire
3 pieces socket
1 piece switch
Tool

Pliers
Working Drawing
Procedure
1. Connect two sockets with bulbs to a dry cell. Observe the brightness of their
lights.
2. Add one more bulb in the setup. Observe the brightness of their light. Does
adding a bulb in the setup affect the brightness of the bulb?
3. Unscrew one bulb in the set up and close the circuit.
4. Unscrew another bulb in the setup. Why does the turning off of one or two
bulbs not break the circuit?
43
5. Trace the path of the electric current flow beginning from the source. How
many paths can the electric current take before returning to the source?
Observation
Steps
Remarks / Comments
First Step
Second Step
Third Step
Forth step
Fifth step
44
Program/Course:
BUILDING WIRING INSTALLATION NC II
Unit of Competency:
FUNDAMENTALS OF ELECTRICITY
Module Title:
Basic Electricity
Learning Outcome 5: Decode resistor value
Assessment Criteria:
1. Different types of resistor are identified.
2. Resistor value is determined according to its color code
3. Importance of resistor tolerance is discussed.
References:
1. Enriquez, Michael Q., Gantalao, Fred T., and Lasala, Rommel M. Simple
Electronics, 2004.
2. Velasco, Benjamin S., Electronics Components Testing Simplified, 1994.
45
LEARNING EXPERIENCES/ACTIVITIES
Learning Outcome 5: Decode resistor value
Learning Activities
Special Instructions
1. Read Information Sheet 5.1
about resistor and its color code.
2. Answer Self-Check 5.1.

Try to answer self-check without
looking at the information sheet.

Provide a separate sheet of paper
as your answer sheet.

Follow the procedure carefully.
3. Answer Activity Sheet 5.1 on
how to decode resistor value.
4. Perform Job Sheet 5.1 on how to
decode resistor value.
46
INFORMATION SHEET 5.1
RESISTOR
Resistors are one of the most common electronic components. A resistor is a
device that limits, or resists the current. Resistor can be made from many
different materials, but the most common is carbon composition. The current
limiting ability or resistance can be varied by charging the ratio of carbon to
binding agent. Resistance is measured in ohms, represented by the Greek
symbol omega (Ω).
1. Carbon Composition is
made either by hot or cold
molding from mixtures of carbon
and clay binder. Its resistive
value ranges from 10 ohms to
mega ohms, in power ranges
from 1/8 to 4 watts. It has the
ability
to
withstand
higher
current surges and ruggedness.
This type is also popular. It is
made from a mixture of carbon
powder and glue-like binder. To
increase the resistance, less
carbon is added. These resistors
show predictable performance, low inductance, and low capacitance. Power
ratings range from about 1/4 to 2 W. Resistances range from 1 Ohm to about
100 MOhm, with tolerances around +/- 5 percent.
47
2. Carbon Film is made
from carbon graphite, mixed
with
powdered
insulating
material. It has two main
characteristics, resistance and
power rating. Carbon resistor
is available in resistance
values from tenths of ohms to
hundred of mega ohms.
3. Metal Film is formed by
means
of
vacuum
decomposition, a process by
which a number of different
metal or metal oxide film is
deposited
on
a
suitable
insulating mandrel or core.
Nickel and chromium are
deposited on the alumina
ceramic core and the unit is
then
subjected
to
laser
trimming.
4. Wire wound highly resistive
wire
is
wrapped
around
insulating core. The length of
the
wire
determines
the
resistance
of
the
device.
Insulating cores are usually
made of cement of ceramic
materials or just plain paper or
pressed cardboard. This type of
resistor provide low resistance,
the unit is encased by
insulating materials.
48
Table showing the color band and its numerical value
Reading a 4-color band resistor
Reading a 5-color band resistor
Resistor color band
49
Examples of resistor reading:
1. A carbon resistor coded BROWN, GREEN, BLACK, and GOLD has the
resistance value of 15 Ohms, and a tolerance of ± 5%.
2. Resistance reading of a carbon composition resistor using the color code.
50
3. Decoding the resistance value of a carbon composition-type resistor using
the EIA color code.
4. Determine the resistor value of a carbon composition resistor using the EIA
color code.
51
5. Determine the resistance reading of a carbon-type using the EIA color code.
52
SELF-CHECK 5.1
Directions: Identify the following. Write your answer on your paper.
1. It is made from carbon graphite, mixed with
powdered insulating material.
2. It is highly resistive wire wrapped around insulating
core.
3. It is made either by hot or cold molding from
mixtures of carbon and clay binder.
4. It is formed by means of vacuum decomposition, a
process by which a number of different metal or
metal oxide film are deposited on a suitable
insulating mandrel or core.
5. It is a device that limits, or resists the current.
53
ACTIVITY SHEET 5.1
DECODE RESISTOR VALUE
Fill out and complete the blank columns in the table with the data/information
required. Write your answer on a separate sheet of paper.
1. What is the resistance value of a carbon resistor coded YELLOW, VIOLET,
YELLOW, NONE as shown below?
2. Determine the resistance value of a carbon resistor coded ORANGE, WHITE,
ORANGE, SILVER as shown below.
54
3. Determine the resistance value of a carbon resistor coded GREEN, BLUE,
YELLOW, NONE as shown below.
4. What is the resistance value of a carbon resistor coded BLUE, GRAY, RED,
GOLD as illustrated below?
55
5. What is the resistance value of a carbon resistor coded ORANGE, WHITE,
YELLOW, NONE as indicated below?
56
JOB SHEET 5.1
DECODE RESISTOR VALUE
Materials

10 different resistors
Procedure
Read the equivalent of the first, second, third and fourth color band, tolerance and
its coded value that correspond on the table.
RESISTOR
No.
FIRST
COLOR
SECOND
COLOR
THIRD
COLOR
FOURTH
COLOR
CODED VALUE TOLERANCE,
(ohms)
±%
1
2
3
4
5
6
7
8
9
10
Table 1. Decoding a carbon resistor
Assessment Criteria
Score
10
8-9
6-7
1-5
Remarks
Excellent
Very satisfactory
Satisfactory
Fair
57
Program/Course:
BUILDING WIRING INSTALLATION NC II
Unit of Competency:
FUNDAMENTALS OF ELECTRICITY
Module Title:
Basic Electricity
Learning Outcome 6: Identify types of capacitors
Assessment Criteria:
1. Different types of capacitors are identified.
2. Capacitor value is converted.
References:
1. Enriquez, Michael Q., Gantalao, Fred T., and Lasala, Rommel M. Simple
Electronics, 2004.
2. Velasco, Benjamin S., Electronics Components Testing Simplified, 1994.
58
LEARNING EXPERIENCES/ACTIVITIES
Learning Outcome 6: Identify types of capacitor
Learning Activities
Special Instructions
1. Read Information Sheet 6.1 about
capacitors.
2. Answer Self-Check 6.1.

Try to answer self-check without
looking at the information sheet.

Provide a separate sheet of paper
for your answer sheet.
3. Answer Activity Sheet 6.1.
59
INFORMATION SHEET 6.1
CAPACITORS
INTRODUCTION
Capacitor is a device that stores energy in the electric field created
between a pair of conductor on which equal but opposite electric charge have
been placed. A capacitor is occasionally referred to using the older term
condenser. A capacitor has two or more conducting plates segregated from each
other by good insulating material called dielectric.
Types of capacitor
1. Electrolytic capacitor – made of electrolyte, basically conductive salt in
solvent. Leaky condition can be checked by connecting the ohmmeter test
leads across the capacitor in one polarity.
2. Ceramic – constructed with materials such as
titanium acid barium for dielectric. Internally, these
capacitors are not constructed as a coil, so they are
suited for use in high frequency applications. They are
shaped like a disk, available in very small capacitance
value and very small size.
3. Polyester film (mylar) – this capacitor uses a thin
polyester film as a dielectric. Not as high tolerance
polypropylene, but cheap, temperature stable, readily
available, widely use. Tolerance is approximately 5% to
10%. It can be quite large depending on capacitor rate
voltage, and so many not be suitable for all application.
60
4. Mica – this type is an extremely accurate
device with very low leakage currents. It is
constructed with alternate layers of metal foil
and
mica
insulation,
stacked
and
encapsulated. These capacitors have small
capacitances and are often used in high
frequency circuits (eg. : RF circuits). They are
very stable under variable voltage and temperature conditions. Tolerances
range from +/-0.25 to +/-5 percent. Capacitances range from 1 pf to 0.01 uF,
with maximum voltage ratings from 100 V to 2.5 kV. This capacitor uses a
thin polyester film as a dielectric
61
CAPACITOR READING
62
Examples:
1.
3,200 picofarad ±5%
= 0.0032
microfarad ±5%
2.
380 picofarad ±10%
= 0.00038
microfarad ±10%
3.
460,000 picofarad
= 0.46 microfarad
4.
2,000 picofarad
= 2,000K
5.
22,000 picofarad
= 0.022
microfarad
63
SELF-CHECK 6.1
Directions: Identify the following. Write your answer on your paper.
1. What type of capacitor is not constructed as coil,
suited for use in high frequency applications?
2. What type of capacitor is an extremely accurate
device with very low leakage currents?
3. What device can store energy in the electric field?
4. What type of capacitor is made of electrolyte?
5. What type of capacitor uses a thin polyester film as
a dielectric?
64
ACTIVITY SHEET 6.1
Direction: Give the equivalent value of the capacitor.
1.
=
2.
=
3.
=
4.
=
5.
=
65
ANSWER KEY 1.1
I. Directions: Read the following sentences carefully. Write the letter of your
answer on a separate sheet.
1. The same electrical charge B
A. attracts
B. repel
each other.
C. destroy
2. It is neither positively nor negatively charged.
A. electron in motion
B. electrostatic force
C. neutron
D. atom
D. neutralize
D.
3. It is the equal number of electron and proton in an atom. C .
A. positive
B. negative
C. neutral
4. The electron theory states that all matter is made of C .
A. neutron
B. atom
C. electron
D. molecules
5. It is the smallest particle of molecule. D .
A. ion
B. proton
C. electron
D. atom
II. Directions: Choose the correct answer in the box below. Write your answer
on a separate sheet of paper.
1. What is the nature of matter? HAS WEIGHT
2. How will you prove that electricity is a matter? OCCUPIES SPACE
3. What is molecule made up? ATOM
4. What is the neutral particle of an atom? NEUTRON
III. Directions: Read each question carefully. Choose the letter of the correct
answer in the box below. Write your answer on a separate
answer sheet.
1. What is found at the center body of an atom? NUCLEUS
2. What do you call the attraction between the nucleus and the electron?
ELECTROSTATIC FORCE
3. What is the positively charged particle of an atom? PROTON
4. What is the negatively charged particle of an atom? ELECTRON
5. What particle of an atom which is not electrically charged? NEUTRON
66
ANSWER KEY 2.1
I. Directions: Match Column A with Column B. Write your answer on a separate
answer sheet.
A
c
1. Friction
d
j
2. Chemical action
3. Heat action
e
f
4. Light action
5. Prezo-electricity
6. Mechanical
action
7. Magnet
b
h
g
8. Magnetic
induction
a
9. Thermoelectricity
i
10. Pressure
B
a. two metals bounded together in junction
by thermocouple process
b. electricity produced by rotating machine
c. electricity generated by rubbing two
materials
d. electricity produced by batteries
e. a process of photo-electricity
f. an action of squeezing or stretching crystal
g. imaginary lines along which the attraction
or repulsion of a magnet act
h. a body having the property of polarity and
of attraction and repulsion found in the
nature.
i. Potential difference appears across the
faces of quartz when squeezed
j. electricity generated by heat action.
II. Directions: From the given words below, choose the correct word that would
complete the sentence. Write your answer on a separate sheet of paper.
fossils fuels
nuclear energy
geothermal
biomass energy
tidal energy
solar energy
Solar energy
1. It is the energy that comes from the sun.
Tidal energy
Geothermal
2. It is the energy that involves water.
3. It is the energy that comes from the inner
core of the earth.
4. It is the result from the splitting or fission
of atomic nuclei.
5. It is the energy formed from the remains of
plant and animals which live thousands of
years ago.
Nuclear energy
Fossil fuels
67
III. Directions: Choose the letter of the correct answer. Write your answer on
your notebook.
D
A
1. The following are the sources of energy except:
A. sun
B. nuclear reaction
C. fossil fuel
D. transformer
2. Which is a nonrenewable source of energy?
A. fossil fuel
B. solar energy
C. tidal energy
D. wind energy
C
3. Which is non-conventional source of energy?
A. fossil fuel B. gasoline
C. solar energy D. hydroelectric power
B
4. The Makiling-Banahaw Plant in Laguna is an example of _______.
A. nuclear power plant
B. geothermal plant
C. hydroelectric power plant
D. fossil fuel- fired plant
D
5. What source of energy is shown in the picture?
A. fossil fuel B. solar energy C. wind energy
D. tidal energy
68
ANSWER KEY 3.1
I. Direction: Label the following splices and joints. Write your answer on a
separate answer sheet.
PLAIN TAP OR TEE
BRITANNIA
RAT TAIL
WRAPPED TAP
KNOTTED OR LOOP
II. Direction: Write the letter of the correct answer o your notebook.
C
1. It is the method of removing insulation from electrical conductor.
A. Pulling
B. Grabbing
C. Skinning
D. Gripping
D
2. What should be done to an insulator from conductor before splicing
or joining the wire?
A. Pull
B. Remove
C. Grab
D. Grip
A
3. What should be the next procedure after removing an insulator from
conductor for soldering a wire?
A. Clean
B. Twist
C. Rub
D. Scrub
69
ANSWER KEY 4.1
I. Directions: Match Column A with Column B. Write your answer on a separate
answer sheet.
A
f
1. Switch
b
d
c
a
2. Source of power
3. Conductor
4. Load
5. Series circuit
connection
6. Parallel circuit
connection
e
B
a. current cannot pass through the bulb when
the other filament of the bulb is cut
b. caused the load to light up
c. consumes power
d. electrical path
e. bulb has its own circuit
f. control the circuit
II.
Directions: Tell whether the following ideas is a series or parallel circuit.
Write S if the answer is series and P if it is parallel on a
separate sheet of paper.
P
S
P
S
1. The total current is the sum of all the current in each circuit.
2. The current throughout the circuit is the same.
3. The voltage is the same in all the circuits.
4. The total resistance in the circuit is the sum of all individual
resistances.
5. The total voltage in the circuit is equal to the sum of the individual
voltages.
S
70
ANSWER KEY 4.2
Directions: Find the missing quantity for each of these circuits.
1.
5Ω
I=2A
V=10
I=2A
2.
R=10
20V
3.
R=5Ω
I=2
10V
I=500A
4.
R=.2
100V
5.
6.
R=10Ω
I=0.4A
V=4.4
25 Ω
I=2
50V
7. An electric heater is rated at 100V and has a hot resistance of 30
ohms. What current will flow through it? 3.3 A
8. An ammeter shows a bulb is using 4 amperes from a 120V source. What
is the resistance? 30 Ω
9. An electric appliance with a resistance of 60 ohms must draw 5A to
operate correctly. What is the correct voltage to use? 300 V
10. How much power is consumed by the machine having a current flow
of 6 ampere supplied by a 220 volt line? 1,320 W
71
ANSWER KEY 5.1
Directions: Identify the following. Write your answer on your paper.
CARBON FILM
1. It is made from carbon graphite, mixed with
powdered insulating material.
WIRE WOUND
2. It is highly resistive wire wrapped around insulating
core.
CARBON
COMPOSITION
METAL FILM
RESISTOR
3. It is made either by hot or cold molding from
mixtures of carbon and clay binder.
4. It is formed by means of vacuum decomposition, a
process by which of a number of different metal or
metal oxide film are deposited on a suitable
insulating mandrel or core.
5. It is a device that limits, or resists the current.
72
ANSWER KEY 6.1
Directions: Identify the following. Write your answer on your paper.
CERAMIC
1. What capacitor is not constructed as coil, suited for
used in high frequency applications?
MICA
2. What type of capacitor that is an extremely accurate
device with very low leakage currents?
3. What device that stores energy in the electric field?
4. What capacitor is made of electrolyte?
CAPACITOR
ELECTROLYTIC
POLYESTER FILM
5. What capacitor uses a thin polyester film as a
dielectric?
73
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