The most industrial and commercial process are depedent on electrical power in the event of power interpretation, the change-over of power supplied by a public utility to a generator is usually performed manually, often resulting in wastage time. Moreover, mechanic and some house hold appliances damages occurs because of human errors. These can cause significant losses. This paper presents a design and construction of an automatic single phase change over switches that electrical power supplying from public to generator is to event of a power outage or insufficient voltage. The system uses electromechanical devices for it’s operation.

TABLE OF CONTENTS

Title page - - - - - - - - i

Certificate page - - - - - - - ii

Dedication - - - - - - - - iii

Acknowledgement - - - - - - - iv

Abstract - - - - - - - - - vi

Table of contents - - - - - - - vii

CHAPTER ONE

Introduction - - - - - - - - 1

Aim of the project - - - - - - 2

Objective of the project - - - - - - 3

CHAPTER TWO

Literature review - - - - - - - 4

Manual change over switch - - - - - 4

Single phase change over switch - - - - 5

Three phase change over switch - - - - 5

An automatic change over switch with automatic generator starter - - - - - - - 6

Important concept used in the project - - - 7

Step down transformation - - - - - 7

Relay contact - - - - - - - - 7

Led indicator -- - - - - - - - 8

Switch - - - - - - - - - 8

CHAPTER THREE

System operation/block, diagram - - - - 9

System operation using block diagram - - - 9

Public power supply PHCN - - - - - 9

Change over electrical isolation - - - - 10

Generator - - - - - - - - 10

Load - - - - - - - - - 10

Circuit diagram - - - - - - - 11

Circuit operation - - - - - - - 12

CHAPTER FOUR

System construction and packaging - - - 13

Circuit layout/prototyping - - - - - 13

Hand writing details/circuit build up - - - 13

Compound sourcing - - - - - - 14

Components - - - - - - - - 15

Miscellaneous - - - - - - - 16

Tools/equipment used - - - - - - 16

Packaging - - - - - - - - 17

System testing and result - - - - - 18

Continuing test and result voltage test - - 18

General function test - - - - - - 19

CHAPTER FIVE

Component/material cost analysis - - - 21

CHAPTER SIX

Summary, conclusion and recommendations - 22

Summary - - - - - - - - 22

Conclusion - - - - - - - - 23

Recommendation - - - - - - - 23

References - - - - - - - - 25

CHAPTER ONE

INTRODUCTION

The need for sufficient power supply without much delay in switching to the alternative service brings about a system which can encounter the delay and losses that occurs in an event of public power failure.

However, power instability in developing countries creates need for automation of electrical power generation or alternative sources of power to back up the utility supply. This automation is required as the rate of power outage becomes predominantly high. Most households, industrial and commercial process department on power supply and the process of changeover are manual, series time is not only wasted but also creates devices or machine damage from human error during the change over connections, which could result in massive losses. This change over switch system separate the source between the generator and public supply, when there is power supply outage from the public supply, with the installation of this system at homes, offices or industries, no man power is required for changing the load line to generator line thus, when the power supply is restored, some one has to put off the generator while the system changes switches itself to the public supply.

AIM OF THE PROJECT