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TVL – ICT
COMPUTER
SYSTEMS
SERVICING NC II
Quarter 1 – Module 3
Preparing ang Interpreting
Technical Drawing (PITD)
(Identify and Interpret the Different Kinds of
Technical Drawings)
(Week 5 – 6)
 What I Need to Know

This module covers the knowledge, skills, attitude, and values

needed to prepare/interpret diagrams, engineering abbreviation and
drawings, symbols and dimensions. The scope of this module permits it to
be used in many different learning situations. The language used
recognizes the diverse vocabulary level of students. The lessons are
arranged to follow the standard sequence of the course. But the order in
which you read them can be changed to correspond with the textbook you
are now using.

The module is divided into two lessons, namely:

Lesson 1 - Identify different kinds of technical drawings

Lesson 2 - Interpret technical drawing

After going through this module, you are expected to:

1. Select correct technical drawing in accordance with the job
requirement
2. Segregate technical drawings in accordance with the types and
kinds of drawings.
3. Recognize components, assemblies, or objects as required
4. Identify dimensions of the key features of the objects depicted in
the drawing
5. Identify and interpret symbols used in the drawing
6. Check and validate drawing against job requirements or equipment
in accordance with standard operating procedure

What I Know

Directions. Please read each statement and select the best answer. Write the
letter and the word. Please use a separate sheet in answering the test. Please do
not forget to write the following in your answer sheet:
Name: _____________________________________ Grade & Section: ___________________
Subject (Specialization): _______________________________Module No.: ____________
Name of the Activity (e.g. What I Know) _____________________ Date: _____________

1. It is represented by a small circle or a connector box and is labelled using

letters.
a. Arrow Line b. Connector c. Flowchart d. Process

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2. It is also known as mistake-proofing.
a. Connector b. Flow Diagram c. Oval d. Poka-yoke
3. It is drawn in one direction, preferably from top to bottom to keep a flowchart
clear.
a. Arrow Line b. Connector c. Flowchart d. Process
4. It is a process is represented by a rectangle with a process is represented by
a rectangle with.
a. Bottle necks b. Flow Diagram c. Sub-process d. Weak links
5. It is resented by a rectangle. It refers to an action in a business process.
a. Arrow Line b. Connector c. Flowchart d. Process
6. Another term of flowchart.
a. Connector b. Flow Diagram c. Oval d. Poka-yoke
7. These are steps where problems occur.
a. Bottle necks b. Flow Diagram c. Sub-process d. Weak links
8. Indicate both the starting point and ending point .
a. Connector b. Flow Diagram c. Oval d. Poka-yoke
9. These points in the process where it slows down these points in the process
where it slows down.
a. Bottle necks b. Flow Diagram c. Sub-process d. Weak links
10. It explains the process clearly through symbols and texts .
a. Arrow Line b. Connector c. Flowchart d. Process

Lesso
n IDENTIFY THE DIFFERENT KINDS

1 OF TECHNICAL DRAWING

Technical drawing is essential for communicating ideas in industry and

engineering. To make the drawings easier to understand, people use familiar
symbols, perspectives, units of measurement, notation systems, visual styles,
and page layout. Together, such conventions constitute a visual language and
help to ensure that the drawing is unambiguous and relatively easy to
understand.

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 What’s In

Sterneckert (2003) stated that the viewpoint of key people in an organization,

such as the manager, analyst, and clerk, can be used as a model in flowcharting.
These persperctives may be applied to the four types of flowchart, provided
below describe the different types of flowchart. Write your answers on your
notebook.

1. Document –
2. Data Flow –
3. System –
4. Program –

What’s New

ENUMERATION: Other than flowchart, give at least five (5) elements that you
can use to represent to your process flows.

1. _________________

2._________________

3._________________

4._________________

5._________________

What is It

What is a Flowchart?

Every now and then, you come across different troubleshooting flowcharts
especially when you service in a computer system. These are normally in the
form of a decision tree which gradually focuses on a solution based on the
criteria set. The usefulness of your flowchart depends on how you manage the

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problems that are answerable using a simple True/False solution. A well-crafted
flowchart can shorten the problem-solving time.

Flowcharts are easy to understand diagrams that show the different steps
in solving a specific problem. Easiness is the key to make flowchart more useful
in communicating how processes works, and for documenting how to do a
specific task.

When to use a Flow Chart?

Flowchart is a very simple yet powerful tool to improve productivity in

both our personal and work life. Here are some ways flowchart can be helpful:

 Document a process
 Present a solution
 Brainstorm an idea
 Design a system
 Explain a decision-making process
 Store information

What are the Basic Symbols of Flowchart?

A flowchart is commonly used by systems analysts to visualize the series

of processes in a business system. A flowchart is a useful tool to design an
efficient business system and to troubleshoot or improve an existing system. A
flowchart consists of elements, such as the terminator, process, sub process,
decision, arrow lines, and connectors.

1. Terminator

Start / End
Terminator Symbol

A terminator is represented by a small rectangle with curved corners. A

terminator appears at the start and at the end of a flowchart. The end terminator
appears only once on a single flowchart.

2. Process

Instructions /
Actions Process Symbol

A process is represented by a rectangle. It refers to an action in a business

process. It must be described clearly and concisely. A process can be described

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using a single verb noun phrase; for example, "Order Office Supplies." The same
level of detail must be kept in processes on a single flowchart.

3. Decision

Decision Decision Symbol

A decision is represented by a diamond. A process that can answer a

decision of "yes" or "no" requires a decision box.

4. Input and Output

Input and
Output Input and Output Symbol

The Parallelogram features Input and Output, which cover such things as
materials, services, and even individuals going into or exiting the process.

5. Connector

Connector Symbol

A connector is represented by a small circle or a connector box and is

labelled using letters. A flowchart written on a single page is clearer than a
flowchart on several pages. A connector ensures that the processes are
connected logically and correctly on several pages.

6. Arrow Lines
Flow Lines Symbol

Arrow lines drawn in one direction, preferably from top to bottom, keep a
flowchart clear. Avoid arrow lines that loop because this could indicate
redundancy in the business process.

HOW TO CREATE FLOW CHART

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1. Identify Tasks. You must list all the tasks in a process in chronological order.
Consider the following questions as your guide:

a. What happens next in the process?

b. Do you need to make a decision before the next step?
c. What approvals are required before you move on to the next task?

2. Organize and Document Tasks. Begin with a rounded rectangle labeled

START. From there, go through the sequences which must include every action
and decision in the intended order. Use arrows to connect them with one another
and to indicate the direction of the process flow. Decisions should be directed by
an arrow from the decision diamond to whatever possible solutions are available.
The arrow should also be labeled with a decision, such as YES, or a NO. The
termination of the process must be marked by a rounded rectangle labeled
FINISH or END.

3. Test. Double-check the flow to make sure that you haven’t overlooked
anything.

Start

Input and
Output

Actions

Choice NO

YES

End

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 OTHER ELEMENTS OF A TECHNICAL
DRAWING

Other than a flowchart, there are several elements that you can still use
to represent your process flows, such as:

 Schematic diagram
 Layout Plan
 Loop diagram
 Chart
 Block diagram

Each of these elements will be discussed in the following pages.

SCHEMATIC DIAGRAM

A schematic diagram is a representation of system elements that are

abstract or symbols which are graphical in nature. It removes all the irrelevant
information.

In the data processing cycle example below, Input/ Output Devices are
represented by a rectangle. The rectangles don’t resemble the actual devices
but give you information without unnecessary visual clutter. The same logic goes

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with the flow of the data and how they are being processed, stored, and
retrieved from the CPU and computer memory.

Central
INPUT OUTPUT
DATA Processing DATA
DEVICES Unit DEVICES

DA

Main/Internal
Main/Internal
Memory
Schematic Diagram

CHART

A chart is a diagram that displays the relationship of at least two variables.

It is often used to easily interpret large quantities of data and relationship
between their parts.

There are four common charts:

 Histogram is a graphical representation of the distribution of numerical

data.

Histogram

 Bar Chart is a graphical representation of grouped data

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 Bar Chart

 Pie Chart is a graphical representation of quantifiable data represented

by a sectioned circle much like a pie that’s been cut with the slices varying
in size.

Pie Chart

 Line Chart is a graphical representation of information as a series of data

points connected by line segments.

Line Chart

BLOCK DIAGRAMS

A block diagram is a specialized type of flowchart. It represents an

encompassing view of major process steps, including the relationships and
interfaces.

Step
Bridge Filter Rechargeable
Down
Rectifier Circuit 9 Battery
T/F
 Regulator

Power supply to all sections

LAYOUT PLANS

A layout is a tool to arrange a workplace, like in a plant, organization, or

computer laboratory in your school. It shows how the computers should be
located and arranged properly according to specifications like the size of the
room and number of units to be installed.

Computer Laboratory Layout Plan

LOOP DIAGRAM

A loop diagram aids you visualizing how items in a system are

interrelated. It consists of a set of nodes that represents the item, and edges that
each represents a connection between two items.

Thread

Event Loop

I/O Events I/O Events

Channel Channel Channel

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 Lesso
n
INTERPRET TECHNICAL DRAWING
2
The essence of having a flowchart in the process analysis is for the
effective delivery of ideas especially if you are dealing with a technical person. A
flowchart explains the process clearly through symbols and text.

What’s In

Direction: Give at least three (3) benefits of flowchart.

1.
2.
3.

What’s New

Direction: Arrange the following steps in developing flowchart. Put the number
(1-7) on a separate sheet of paper.

____________1. Define the process to be flowcharted, and the purpose for

flowcharting it.
___________ 2. Establish process boundaries - the starting and ending points.
____________3. Put the steps in chronological sequence. Sometimes it's easier to
start with the last step and work back to the first step.
____________4. Assign flowchart symbols such as boxes, diamonds, and triangles.
____________5. Review and title the flowchart.
____________6. Assemble the right people to develop the flowchart— those
operators, technicians, or office workers who are involved in the process.
____________7. List the steps, activities, and decisions to be charted. If your team
is not sure about a step, mark it to be investigated later.

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 What is It

In this lesson, you will understand the reasons why you need to:

 know how a process is done;

 study and improve processes;
 document a process; and
 use a flowchart in planning a project or activity.

SIMPLE REMINDER IN USING A FLOWCHART

 There is no such thing as a proper way of constructing a flowchart. What’s

important is how the people involved understand the process.
 Involve only the key people in the flowcharting process.
 A technical expert is not necessary to draw a flowchart. It should be you
who performs the process.
 There a lots of free flowcharting software that you can use.

MISTAKE-PROOFING

Mistake cannot be avoided sometimes when making flowcharts, but the

chances for errors in the process can be reduced by deviating from the
usual steps or actions that have resulted in mistakes. Mistake-proofing
solutions can eliminate redundant process actions and give way to new
and untried methods that provide better solutions.

In japan, where the work ethic is admired worldwide, mistake-proofing is

known as poka-yoke (PO-ka yo-KAY). It is simply a system that reduces
mistakes and in Flowchart instances when an error does occur, it is quickly
identified and addressed.

MISTAKE-PROOFING IN YOUR DAY-TO-DAY ACTIVITY

Although you often don’t see it poka-yoke is all

around us. An example is the thumb drive. The
thumb device can only be inserted if it is oriented
properly. It cannot be inserted in the reverse side
or sideways.

The designers of the thumb drive thought it best to

make it self-limiting in how it’s used based on how the device is oriented. It’s like
a program which works only one way. If not used in that manner, it simply won’t
work. It’s design strategy that does way with having to teach the user how to use
the device, thus eliminating the risk for error in use.

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How do you interpret flowcharts?

A Flowchart will help you understand your process and uncover ways to improve
it only if you use it to analyze what is happening. Interpreting your Flowchart will
help you to:

 Determine who is involved in the process.

 Form theories about root causes.
 Identify ways to streamline the process.
 Determine how to implement changes to the
process.
 Locate cost-added-only steps.
 Provide training on how the process works or
should work.

Below is a sequence of steps that will help you through an orderly analysis of
your flowchart.

Step 1 - Examine each process step for the following conditions that indicate
a need to improve the process:

Bottlenecks. These points in the process where it slows down may be

caused by redundant or unnecessary steps, rework, lack of capacity, or
other factors.

Weak links. These are steps where problems occur because of inadequate
training of process workers, equipment that needs to be repaired or
replaced, or insufficient technical documentation. "Inform the drill leader
and improvise" is one of the weak links.

Poorly defined steps. Steps which are not well-defined may be interpreted
and performed in a different way by each person involved, leading to
process variation. "Improvise" is a poorly defined step in the weak link
cited above.

Step 2 - Examine each decision symbol.

You may want to collect data on how often there is a "yes" or "no" answer at
decision points marked by a diamond shaped symbol. If most decisions go one
way rather than the other, you may be able to remove this decision point.

Step 3 - Examine each rework loop.

Processes with numerous checks generate rework and waste. Examine the
activities preceding the rework loop and identify those that need to be improved.
Look for ways to shorten or eliminate the loop.

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Step 4 – Examine each activity symbol.
Does the step help build a key quality characteristic into the end product? If not,
consider eliminating it.

Besides the three levels of detail used to categorize Flowcharts, there are three
main types of flowcharts namely , linear, deployment, and opportunity. The
level of detail can be depicted as macro, mini, or micro for each of these types.

1. Linear Flowchart. A linear flowchart is a diagram that displays the sequence

of work steps that make up a process. This tool can help identify rework and
redundant or unnecessary steps within a process.

2. Deployment Flowchart. A deployment flowchart shows the actual process

flow and identifies the people or groups involved at each step. Horizontal lines
define customer-supplier relationships. This type of chart shows where the
people or groups fit into the process sequence, and how they relate to one
another throughout the process.

HOW DO WE CONSTRUCT A LINEAR FLOWCHART?

Following are the seven steps for developing a linear flowchart

1. Define the process to be flowcharted, and the purpose for flowcharting it.

2. Assemble the right people to develop the flowchart—those operators,

technicians, or office workers who are actually involved in the process.

3. Establish process boundaries—the starting and ending points.

 Identify the major activities or sub processes that are included in the
process.
 Determine what is not included in the scope of the process to remove any
doubt or confusion about the boundaries. This may also help establish the
scope of related processes.

4. List the steps, activities, and decisions to be charted. If your team is not
sure about a step, mark it to be investigated later.

5. Put the steps in chronological sequence. Sometimes it's easier to start

with the last step and work back to the first step.

6. Assign flowchart symbols such as boxes, diamonds, and triangles.

7. Review and title the Flowchart.

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CONSTRUCTING A LINEAR FLOWCHART

Define the process

and the purpose

Assemble the right

people

Establish process
boundaries

Are steps in
sequence? Put steps in
sequence

Assign flowchart
symbols

Review and label

Flowchart

What’s More

Direction: Match Column A with Column B. Write only the letter of the correct
answer on your notebook.
Name: _____________________________________ Grade & Section: ___________________
Subject (Specialization): _______________________________Module No.: _____________
Name of the Activity (e.g. What’s More) ______________________ Date:
______________

1. A connector ensures that the process are connected a.

logically and correctly on several page.

2. Shows a decision point, such as yes/no or go/nogo. b.

3. Indicates both the starting point and the ending c.

point of the process steps

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4. Drawn in one direction, preferably from top to bottom d.

5. Shows where an in-process measurement occurs. e.

What I Have Learned

Direction: Fill In The Blanks. Identify the word/s that best describe/s the
following statements. Use your activity sheet to write your answers.
____________1. Work through all the steps in your chart to make sure they are
clear and exhaustive, and that there is no open-ended node
remained.
____________2. Indicates the beginning or end of a flowchart.
____________3. Represent a step in a process. This is the most common
component of a flowchart.
____________4. Shows a step that decides the next step in a process. This is
commonly a yes/no or true/false question.
____________5. Shows the process’ direction. Each flowline connects two blocks.
____________6. An optional step here is to style your chart with different shapes
and color to make it easier to follow.
____________7. Flowcharts should be made easily accessible to all parties
involved.
____________8. Represents an individual step or activity in the process.
____________9. shows where an in-process measurement occurs.
____________10. is a mark, sign, or word that indicates, signifies, or is understood
as representing an idea, object, or relationship.

What I Can Do

Name: _____________________________________ Grade & Section: ___________________

Subject (Specialization): _______________________________Module No.: _____________
Name of the Activity (e.g. What I Can Do) _____________________ Date:
_____________

Direction: Using the basic symbols used for flowchart, make your own simple
flowchart to illustrate the process of cleaning the computer parts and
peripherals properly. Include the given activities below.

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 1. Preparation of cleaning tools
2. Identifying the parts to be clean
3. Cleaning the different peripheral

SCORING RUBRICS:

Preparatio
Accomplishe Developin Beginnin
n of Exemplary Scor
d g g
Flowchart 4 e
3 2 1
s
All assigned Almost all Almost all Fewer
details and assigned assigned than 85%
Drawing elements details / details of the
have elements (at and assigned
been least 85%) elements details and
added. The have been (at least elements
details are added. The 85%) have are
clear details are been present
and easy to clear and added. A OR most
identify. easy to few details details are
identify. are difficult to
difficult to identify.
identify.

Takes Tries his or Always goes Does not Works

ownership her best, for the best of always below
for learning asks for their ability work to ability
feedback or and gets help ability and level and
help when when needed seldom does not
needed, asks for ask for
helps others help. help
understand
the topic
better
Total
Interpretation of Scores
7- 8 Excellent
5-6 Very Good
3-4 Good
1-2 Fair
0-1 Poor

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 Assessment

Directions. Please read each statement and select the best answer. Write the
letter and the word. Please use a separate sheet in answering the test. Please do
not forget to write the following in your answer sheet:
Name: _____________________________________ Grade & Section: ___________________
Subject (Specialization): _______________________________Module No.: ____________
Name of the Activity (e.g. Assessment) _____________________ Date: _____________
1. What symbol in flowcharting that is drawn in one direction, preferably from
top to bottom to keep a flowchart clear.
a. Arrow Line b. Connector c. Flowchart d. Process
2. These are steps where problems occur because of inadequate training of
process workers, equipment that needs to be repaired or replaced, or
insufficient technical documentation .
a. Bottle necks b. Flow Diagram c. Sub-process d. Weak links
3. It is a process is represented by a rectangle with a process is represented by
a rectangle with.
a. Bottle necks b. Flow Diagram c. Sub-process d. Weak links
4. One of the basic symbols of flowcharting that is represented by a small circle
or a connector box and is labelled using letters .
a. Arrow Line b. Connector c. Flowchart d. Process
5. It explains the process clearly and systematically through symbols and texts .
Arrow Line b. Connector c. Flowchart d. Process
6. It is one of the basic flowcharting symbols that indicate both the starting
point and ending point.
a. Connector b. Flow Diagram c. Oval d. Poka-yoke
7. On of the basic flowcharting symbols that is resented by a rectangle. It
refers to an action in a business procedure.
a. Arrow Line b. Connector c. Flowchart d. Process
8. It is also known as mistake-proofing.
a. Connector b. Flow Diagram c. Oval d. Poka-yoke
9. Flowchart is a very simple yet powerful tool to improve productivity in both
our personal and work life. What is another term of flowchart?
a. Diagram b. Flow Diagram c. Process d. Workflow
10. These points in the process where it slows down may be caused by
redundant or unnecessary steps, rework, lack of capacity, or other factors .
a. Bottle necks b. Flow Diagram c. Sub-process d. Weak links

Additional Activities

Directions: Draw at least five (5) basic elements of flowchart and name the
symbol and its purpose. Write your answers on your notebook. (2 points each)

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 SYMBOL SYMBOL NAME PURPOSE
1.
2.

3.

4.

5.

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