Basic Electricity - Senior Secondary 3 - Earthing

Earthing

Get it on Google Play
Get it on the Apple App Store
  1. Home
  2. Comprehensive Lesson Plan and Notes
  3. Senior Secondary 3
  4. Earthing

TERM: 1ST TERM

WEEK SEVEN

Class: Senior Secondary School 3

Age: 17 years

Duration: 40 minutes of 5 periods each

Date:

Subject: BASIC ELECTRICITY

Topic: EARTHING

SPECIFIC OBJECTIVES: At the end of the lesson, pupils should be able to

I.) Define electrical earthing

II.) State the importance of electrical earthing

III.) Identify the methods of Electrical Earthing

INSTRUCTIONAL TECHNIQUES: Identification, explanation, questions and answers, demonstration, videos from source

INSTRUCTIONAL MATERIALS: Videos, loud speaker, textbook, pictures,

INSTRUCTIONAL PROCEDURES

PERIOD 1-2

PRESENTATION

TEACHER’S ACTIVITY

STUDENT’S

ACTIVITY

STEP 1

INTRODUCTION

The teacher explains the meaning of electrical earthing and discuss the importance of earthing

Students listens attentively to the teacher                                                                          

STEP 2

EXPLANATION

Teacher identify and discuss the types of earthing.

Students exhibit attentiveness and active engagement

STEP 3

NOTE TAKING

The teacher writes a summarized

note on the board

The students

copy the note in

their books

 

NOTE

EARTHING

Electrical earthing, also known as grounding, refers to the process of connecting electrical systems, equipment, and conductive parts to the Earth or a grounding system. The primary purpose of electrical earthing is to provide a safe path for the dissipation of electrical faults, leakage currents, and transient voltages to the ground, thereby reducing the risk of electric shock, equipment damage, and fire hazards.

Importance of Electrical Earthing

  1. Earthing helps prevent electric shocks by providing a low-resistance path for fault currents to flow safely into the ground, minimizing the risk of injury to humans and animals.
  2. Earthing protects electrical equipment and appliances from damage caused by transient voltages, lightning strikes, and electrical faults by diverting excessive currents away from sensitive components.
  3. Proper earthing reduces the likelihood of electrical fires by effectively dissipating fault currents and preventing overheating of conductors and equipment.
  4. Earthing dissipates static charges that accumulate on conductive surfaces, reducing the risk of electrostatic discharge and damage to electronic devices.
  5. Earthing reduces electromagnetic interference (EMI) and radio frequency interference (RFI) by providing a reference ground potential for electrical systems, improving signal integrity and equipment performance.

Methods of Electrical Earthing

  1. Rod Earthing: A metal rod or electrode, usually made of copper or galvanized steel, is driven into the ground and connected to the electrical system or equipment through a conductor.
  2. Plate Earthing: Large metal plates buried underground or installed horizontally on the surface provide an earthing connection for electrical systems. Multiple plates may be used to increase the earthing area and reduce resistance.
  3. Pipe Earthing: Metal pipes, such as steel or copper pipes, driven vertically into the ground, serve as earthing electrodes. They are filled with conductive compounds or salts to enhance conductivity.
  4. Strip Earthing: Metal strips or tapes buried in trenches or laid on the surface are used for earthing, especially in industrial installations or substations.

EVALUATION: 1. What is electrical earthing?

  1. Mention 5 importance of electrical earthing
  2. State 5 methods of earthing

CLASSWORK: As in evaluation

CONCLUSION: The teacher commends the students positively