Class: Senior Secondary School 1 (SS1 / SSS 1)
Term: 2nd Term
Week: 9
Age: 15 years
Duration: 45 minutes
Subject: Electrical Installation and Maintenance Work
Curriculum Theme: Technology
Previous Lesson: Introduction to Conduit System of Wiring: Meaning, Types and Advantages.
Topic: INTRODUCTION TO CONDUIT SYSTEM OF WIRING.
Subject Matter: Conduit components identification, piping in conduit wiring, wiring through conduit, fitting conduit accessories, uses of circular boxes terminal angle tee 4 way 2 hole loop in knockout box.

Specific Objectives

By the end of the lesson, pupils should be able to:

Cognitive Domain:

Define a conduit wiring system.
Identify various components of a conduit wiring system.
Explain the uses of different conduit accessories.

Affective Domain:

Appreciate the importance of using conduit for safe electrical wiring.
Develop an interest in proper installation techniques for electrical conduits.

Psychomotor Domain:

Demonstrate how to pipe conduits.
Demonstrate how to wire through conduits.
Fit conduit accessories correctly.

Work collaboratively during practical demonstrations.

Reference Materials

The following resources were used in planning this lesson:

9 Years Basic Education Curriculum for Electrical Installation and Maintenance Work.
State Unified Scheme of Work for Senior Secondary Schools.
Electrical Installation Technology by L.S. Eze.
https://nigerianembassy.org.ng/wp-content/uploads/2019/08/SENIOR-SECONDARY-EDUCATION-CURRICULUM-ELECTRICAL-INSTALLATION-AND-MAINTENANCE-WORK.pdf
https://www.waeconline.org.ng/e-learning/EIMW/EIMW.html

Instructional Materials

The teacher will teach this lesson with the aid of:

Various types of circular boxes (junction, terminal, loop-in, knockout).
Terminal angle box, tee box, 4-way box, 2-hole loop-in box, knockout box.
Samples of PVC and metallic conduit pipes.
Electrical wires (conductors).
Measuring tape, hacksaw, conduit bender, screwdrivers, fish tape (pull wire).

Rationale for the Lesson

This lesson helps pupils understand how to protect electrical wires using conduit systems. This knowledge is important for ensuring safety in electrical installations and for organizing wiring neatly in buildings, which helps prevent electrical hazards.

Prerequisite/Previous Knowledge

Pupils should have basic knowledge of electrical safety, simple electrical circuits, and different types of electrical wires.

Lesson Content/Board Summary

INTRODUCTION TO CONDUIT SYSTEM OF WIRING

Definition of Conduit Wiring System

A conduit wiring system is an electrical installation method where insulated electrical conductors (wires) are enclosed and protected within pipes or tubes, known as conduits. These conduits can be made of metal or plastic (PVC).

Conduit Components and Their Uses

The following are common conduit components and their uses:

Conduit Pipes: These are the main tubes that protect the electrical wires from mechanical damage, moisture, and chemical attack. They can be rigid (metal or PVC) or flexible.
Circular Boxes: These are round boxes used for making connections, joining conductors, or providing access points for inspection and maintenance.
Elbows/Bends: Used to change the direction of the conduit run at specific angles (e.g., 90-degree bend).
Couplers: Used to join two lengths of conduit pipes together to form a continuous run.
Saddles: Used to securely fix conduit pipes to walls, ceilings, or other surfaces. They come in various types like spacer saddles and half saddles.
Inspection Boxes: These are boxes with removable covers, allowing for easy inspection, pulling of wires, and maintenance without disturbing the entire conduit run.
Bushings: Fitted at the ends of conduits where wires exit, to protect the wires from abrasion by the sharp edges of the conduit.

Piping in Conduit Wiring

Piping in conduit wiring refers to the process of installing the conduit pipes according to the wiring plan. The steps involved include:

Marking the layout of the conduit run on the walls or ceiling.
Cutting conduit pipes to the required lengths using a hacksaw.
Bending conduits using a conduit bender to achieve desired angles and curves.
Fixing the conduits to the surfaces using appropriate saddles and screws.
Connecting different sections of conduits using couplers and fitting them into various boxes (e.g., circular boxes, inspection boxes).

Wiring Through Conduit

Wiring through conduit is the process of pulling electrical conductors (wires) inside the installed conduit pipes. This typically involves:

Using a fish tape or pull wire to thread through the conduit from one access point to another.
Attaching the electrical wires to the end of the fish tape.
Carefully pulling the wires through the conduit, ensuring they do not get tangled or damaged.
Avoiding overcrowding of wires within the conduit to prevent overheating and make future maintenance easier.

Fitting Conduit Accessories

Fitting conduit accessories involves securely attaching various components like circular boxes, inspection boxes, and other fittings to the conduit system and mounting surfaces. This ensures the integrity and functionality of the entire wiring system.

Uses of Specific Conduit Boxes

The following are the uses of specific conduit boxes:

Circular Box (Junction Box): Primarily used for making connections or joints between conductors, or for diverting wires to different points in a circuit.
Terminal Angle Box: Used to terminate a conduit run when the wiring needs to turn at an angle, often to connect to a switch or a fitting mounted on an adjacent surface.
Tee Box: Used to create a three-way junction in a conduit run, allowing one conduit to branch off from a main run.
4-Way Box: Used to create a four-way junction in a conduit run, allowing conduits to enter and exit from four different directions.
2-Hole Loop-in Box: Designed to allow conductors to be “looped in” without making a joint inside the box, typically used for lighting points where the supply is looped from one lamp holder to the next.
Knockout Box: A versatile box with pre-punched, removable sections (knockouts) that can be easily removed to allow conduit pipes to be connected. These are commonly used for switches, sockets, and other accessory mounting.

Teaching Methods/Instructional Techniques

Discussion, Lecture, Demonstration, Question and Answer, Visual Aids

Instructional Procedures

Step 1: Introduction

Time: 5 minutes
Teaching Skill: Set Induction
Teacher’s Activity: The teacher greets the pupils, reviews the previous lesson briefly, and then introduces the new topic by asking pupils if they have seen electrical wires inside pipes in buildings and why they think this is done.
Pupils’ Activity: Pupils respond to the questions and listen attentively.
Learning Point: Pupils are introduced to the concept of conduit wiring and its purpose.

Step 2: Identification of Conduit Components

Time: 10 minutes
Teaching Skill: Demonstration/Identification
Teacher’s Activity: The teacher displays various conduit components (pipes, circular boxes, elbows, saddles, etc.) and names each component, allowing pupils to handle them if safe and appropriate.
Pupils’ Activity: Pupils observe, listen to the names of the components, and identify them.
Learning Point: Pupils identify different components of a conduit wiring system.

Step 3: Explanation of Uses of Conduit Components

Time: 7 minutes
Teaching Skill: Explanation/Discussion
Teacher’s Activity: The teacher explains the specific uses of each displayed conduit component, emphasizing their role in protecting wires and facilitating proper installation. Special focus is given to the various types of circular boxes.
Pupils’ Activity: Pupils listen, ask questions for clarification, and take notes.
Learning Point: Pupils understand the functions of various conduit components and accessories.

Step 4: Demonstration of Piping in Conduit Wiring

Time: 7 minutes
Teaching Skill: Demonstration
Teacher’s Activity: The teacher demonstrates how to cut a conduit pipe, bend it using a bender, and fix it to a surface with saddles, connecting it to a circular box.
Pupils’ Activity: Pupils observe the demonstration carefully, noting the steps involved.
Learning Point: Pupils observe the practical steps for piping in conduit wiring.

Step 5: Demonstration of Wiring Through Conduit and Fitting Accessories

Time: 7 minutes
Teaching Skill: Demonstration
Teacher’s Activity: The teacher demonstrates how to pull wires through a pre-installed conduit using a fish tape and how to correctly fit accessories like a knockout box or a terminal angle box.
Pupils’ Activity: Pupils watch the demonstration, paying attention to the techniques used.
Learning Point: Pupils observe how to wire through conduits and fit accessories.

Step 6: Practical Session/Pupils’ Activity

Time: 5 minutes
Teaching Skill: Practical Application
Teacher’s Activity: The teacher guides pupils (individually or in small groups) to briefly practice simple tasks like identifying components or attempting to connect a pipe to a box, under close supervision.
Pupils’ Activity: Pupils engage in hands-on practice, applying what they have learned.
Learning Point: Pupils gain practical experience in handling conduit components.

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

Define a conduit wiring system.
List four components of a conduit wiring system.
State two uses of a circular box.
Explain one step involved in piping in conduit wiring.
Mention two accessories used in conduit wiring.

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Pupils demonstrate understanding of the lesson.

Step 8: Conclusion

Time: 1 minute
Teaching Skill: Summarization
Teacher’s Activity: The teacher summarizes the key points of the lesson and gives pupils an assignment to draw and label five conduit components.
Pupils’ Activity: Pupils listen to the summary and copy the assignment.
Learning Point: Pupils consolidate their understanding and are given tasks to reinforce learning.

Lesson Keywords

Conduit: A protective tube or pipe, usually made of metal or PVC, used to enclose and protect electrical wires.
Piping: The process of installing conduit pipes along a designated path for electrical wiring.
Wiring: The act of pulling or threading electrical conductors (wires) through the installed conduit pipes.
Circular box: A round electrical box used in conduit systems for junctions, terminations, or mounting accessories.
Knockout box: An electrical box with removable sections (knockouts) that can be easily detached to create openings for conduit connections.

Differentiation

For pupils who grasp concepts quickly, the teacher can challenge them to identify more complex conduit arrangements or research different types of conduit materials. For pupils needing more support, the teacher can provide additional visual aids, simplified diagrams, or one-on-one guidance during the practical session to ensure they can identify basic components and understand their uses.

Note for teachers using this lesson plan

Ensure all demonstrations are carried out with safety as the priority. Use non-live components for practical demonstrations and ensure pupils understand the dangers of working with electricity. Encourage active participation and questions. Having actual samples of all components is highly beneficial for pupil understanding.