Scale Reading: Measuring Instruments in TLE

Content Standards and Learning Competencies

Content Standards

The learners demonstrate an understanding of the concepts and principles in performing mensuration and calculations.

Performance Standards

The learners perform mensuration and calculations following safety precautions

Learning Competency

Interpret the readings in different measuring instruments.

Learning Objectives

1

Explain the function and uses

Students will be able to explain the function and uses of tachometer, oscilloscope, and ampere meter.

2

Identify the parts

Students will be able to identify the parts of the tachometer, oscilloscope, and ampere meter.

3

Interpret the readings

Students will be able to interpret the readings of tachometer, oscilloscope, and ampere meter.

Activating Prior Knowledge

Pass the Cabbage

Create a cabbage-like vegetable made of crumpled papers, cabbage will be passed to one another as the class sings any type of song.

Music Stops

Once the music stops, a student who got the cabbage will peel one page and answer the question that is written on the cabbage paper.

Answer Questions

Questions will be about VOM Scale, Ohmmeter Function and Voltmeter Function, as well as students' personal experiences with these tools.

Lesson Purpose and Intention

Let's explore how multitesters connect to our everyday experiences:

Family Connections

Think about times when your grandfather, father, uncle, or elder brother may have used a multitester at home for repairs. What were they fixing? How did they use this tool?

Professional Applications

Share your experiences seeing multitesters being used by professionals or family members. What did you observe about how they worked with this tool?

Exploring the Tool

Take a moment to examine this multitester. Does it look familiar to you? Have you seen similar tools before? What do you think different parts of it might do?

Unlocking Content Vocabulary

Tachometer

It is an instrument that measures the working speed of an engine, typically in revolutions per minute (RPM).

Oscilloscope

It is an instrument that graphically displays electrical signals and shows how those signals change over time.

Ammeter

It is a measuring device that measures the flow of current in a circuit.

Milliammeter

A measuring instrument that measures small electrical currents (milliamps).

Understanding Tachometers

Analog Tachometer

A traditional dial-type tachometer that measures engine speed in revolutions per minute (RPM). Commonly found in cars and other vehicles.

Digital Tachometer

Modern tachometers often use LCD or LED screens to display engine speed measurements with precise digital readouts.

Aircraft Application

Tachometers are essential in aircraft to monitor engine performance and ensure safe operation during flight.

Industrial Use

Beyond vehicles, tachometers are widely used in industrial machinery to monitor rotational speeds and ensure optimal performance.

Types of Tachometers

Analog Tachometer

Uses a series of reeds that detect engine speed. Works with centrifugal force, extending and compressing mechanical springs to count RPM based on the period.

Electronic Tachometer

A component in your car's dashboard that measures engine speed in RPM. Uses a magnetic pickup in the rotating engine to produce electric pulses with frequency proportional to engine speed.

Mechanical Tachometer

Uses a flexible shaft and gears to measure speed. Often found in older vehicles and industrial machinery.

Digital Tachometer

Displays readings digitally rather than using a needle and dial. More accurate and easier to read.

Optical Tachometer

Uses a laser or light beam to detect rotational speed. Often used in industrial applications.

Importance of a Tachometer

Prevents Engine Over-revving

Helps drivers and operators avoid exceeding safe RPM levels.

Improves Fuel Efficiency

Encourages proper gear shifting for better fuel economy.

Enhances Engine Performance

Ensures optimal RPM for smooth operation.

Prevents Engine Damage

Prolongs engine lifespan by avoiding excessive strain.

How to Read a Tachometer in a Vehicle

Locate the Gauge

The tachometer gauge is usually found on the dashboard of a car.

Understand the Numbers

It shows the RPM of the engine, often marked with numbers like 1, 2, 3, etc., each representing 1,000 RPM.

Identify the Red Zone

The red zone (often starting at 5,000 or 6,000 RPM) indicates dangerous levels of engine speed.

Maintain Safe Range

Drivers should keep the RPM within the recommended range for smooth and efficient driving.

Real-World Applications of Tachometers

Automobiles

Helps drivers monitor engine speed and shift gears properly.

Aircraft

Ensures safe and efficient operation of airplane engines.

Industrial Machines

Used to measure motor speeds in factories and production lines.

Medical Equipment

Found in devices like centrifuges to maintain precise rotations.

Parts of a Tachometer

1

Contact Measuring Device

A key part of the whole tachometer.

2

RPM Adapter

The element that contacts the object the speed of which you want to measure.

3

Function Switch

Used to switch between the units of measurement.

4

Memory Call Button

Used to show the last reading.

Additional parts include the display (shows the readings or result), measure button (used to start the measurement), and battery cover (used to cover and protect the battery from dust and any damage).

Tachometer Reflection Questions

Personal Relevance

Reflect on your own vehicle experiences. Based on what we discussed today, do you think tachometer displays an important role in our daily living?

Observational Learning

Recall the time when you observed someone driving a vehicle. How did this lesson impact you as a person riding any type of vehicle?

Vehicle Operator Activity

Activity Instructions

Students will portray as a vehicle operator

Planning Task

List plans to be done before driving or operating a vehicle

Worksheet Completion

Complete worksheet #1 with your answers

Synthesis and Extended Learning

What You Have Learned

In a one sheet of paper write something you understand about the lesson we discussed today.

Personal Reflection

Consider how this knowledge might be useful in your future technical projects or everyday life.

Further Exploration

Research additional applications of tachometers in fields that interest you.

Evaluating Learning: Tachometer Quiz

1

Primary Function

What is the primary function of a tachometer?

A. Measure temperature�B. Measure engine speed (RPM)�C. Measure fuel consumption�D. Measure vehicle speed

2

Measurement Units

In which unit does a tachometer usually display engine speed?

A. Miles per hour (MPH)�B. Revolutions per minute (RPM)�C. Kilometers per hour (KPH)�D. Pounds per square inch (PSI)

3

Tachometer Types

What type of tachometer uses a magnetic sensor to detect rotational speed?

A. Mechanical tachometer�B. Optical tachometer�C. Digital tachometer�D. Electronic tachometer

Evaluating Learning: More Quiz Questions

1

Location

Where is a tachometer commonly found in a vehicle?

A. On the fuel tank�B. On the dashboard�C. On the exhaust pipe�D. Inside the transmission

2

Importance

Why is it important to monitor a vehicle's tachometer while driving?

A. To ensure the vehicle is not exceeding speed limits�B. To prevent the engine from over-revving and getting damaged�C. To check the temperature of the tires�D. To measure the oil level in the engine

Answers: 1.B, 2.B, 3.D, 4.B, 5.B

Additional Activities for Application

Definition Question

What is a tachometer, and what is its main function?

Importance Question

Why is it important for drivers to monitor the tachometer in their vehicles?

Comparison Question

Differentiate between a mechanical and an electronic tachometer.