ATE210 – Electrical Workshop

Module 3: Basic Electrical Components 2

Module 3: Basic Electrical Components

Module Objectives

Upon successful completion of this module, students should be able to:

1. Identify basic electrical components such as:

Lamps, motors and buzzers.

Resistors, LDRs, capacitors and inductors.

Diodes.

2. State the application of each component.

Module Contents:

Topic Page No.

3.1 Introduction 3

3.2 Basic Electrical Components 3

3.3 Components Coding 6

3.4 Class and Lab Activities 9

3.5 Review Exercise 14

ATE210 – Electrical Workshop

Module 3: Basic Electrical Components 3

3.1 Introduction Have you ever opened your personal computer (PC) or your radio from the inside? If

you tried so, have you seen the electrical boards with many components mounted on

them? Figure 3.1 shows an example of a PC electrical board with different

components. In this module, we will study these components and understand their

usages and applications.

Figure 3.1: PC Electrical Board

3.2 Basic Electrical Components

Component Symbol Function Picture

Lamp

Light Indicator

Motor

Motion Indicator

Buzzer

Sound Indictor

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Module 3: Basic Electrical Components 4

Component Symbol Function Picture

Resistor

Resistors limit the current flow

Variable Resistor

Variable resistors control the current in the circuit:

- Adjust lamp brightness - Adjust motor speed

They are also called potentiometers

LDR (Light Dependent Resistor)

LDRs are variable resistors where resistance value changes with light

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Module 3: Basic Electrical Components 5

Component Symbol Function Picture

Capacitor

Capacitors store electrical charge and are used in:

- Timer Circuits

Inductor

Inductors store magnetic field and are used in:

- Electric bells - Door locks

Diode

Diodes allow current to flow in one direction only. Diode has two terminals:

1. Cathode (K)(-) : located to the line perpendicular to the point of the arrowhead

2. Anode (A) (+): located at the opposite end of the cathode.

ATE210 – Electrical Workshop

Module 3: Basic Electrical Components 6

3.3 Components Coding: 1. Resistance Coding: Resistors are specified by their resistance value and their

tolerance. One way to indicate the resistance value and tolerance is color code method, which is explained in Figure 3.2.

1. Resistance is measured in ohms (Ω) 2. Most resistors have 3 bands:

• The 1st band gives the first digit. • The 2nd band gives the second digit. • The 3rd band indicates the number of zeros. • The 4th band gives the tolerance

Figure 3.2 Resistance color code