Design And Implementation Of A 200A Automatic Changeover Switch With Phase Selector And Power Failure Alarm

ABSTRACT

This project work is on the design and construction of automatic changeover switch with phase selector and power failure alarm. It provides a means of switching from one phase of AC mains to another in the case of failure in the existing phase; it also changeover to generator if there is failure in all the three phases of the AC mains. The circuit also senses the restoration of any or all the three phases of the mains and changeover without any notice of power outage. This project has been improved on the existing types of electromechanical device that has being in use over the years.

Hence this has been achieved by the use of operational amplifier, timing circuit and high current relay switches and it is powered by 12V dc power supply. The aim of this work is to design and construct an Auto Phase Selector introduces an automatic solution to overcome power fluctuation/phase interruption by selecting next most healthy available phase to feed the equipment without any notice of power outage. The function of power failure alarm is to inform the loss of power supply in the whole system.

TABLE OF CONTENTS

 TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWLEDGEMENT

ABSTRACT

TABLE OF CONTENT

CHAPTER ONE

• INTRODUCTION
• BACKGROUND OF THE PROJECT
• AIM/OBJECTIVE OF THE PROJECT
• SIGNIFICANCE OF THE PROJECT
• PURPOSE OF THE PROJECT
• STATEMENT OF PROBLEM
• LIMITATION OF THE PROJECT
• APPLICATION OF THE PROJECT
• DEFINITION OF TERMS
• PROJECT ORGANIZATION

CHAPTER TWO

LITERATURE REVIEW

2.0     LITERATURE REVIEW

2.1     REVIEW OF ELECTRICAL PHASES

2.2     REVIEW OF THREE-PHASE ELECTRIC POWER

2.3      REVIEW OF CAUSES OF POWER FAILURES

2.4       POWER SUPPLY RELIABILITY

 CHAPTER THREE

3.0      CONSTRUCTION METHODOLOGY

3.1      BLOCK DIAGRAM OF THE SYSTEM

3.2     CIRCUIT DIAGRAM

3.3     CIRCUIT DESCRIPTION

3.4     SYSTEM OPERATION

3.5      COMPONENTS LIST

3.6     DESCRIPTION OF MAJOR COMPONENTS USED

CHAPTER FOUR

4.0       RESULT ANALYSIS

4.1     CONSTRUCTION PROCEDURE AND TESTING

4.2     ASSEMBLING OF SECTIONS

4.3     CONSRUCTION OF THE CASING

4.4     ECONOMIC OF THE PROJECT

4.5     PROJECT VIABILITY

4.6     PROJECT RELIABILITY

4.7     PROJECT MAINTAINABILITY

4.8      PROJECT EVALUATION

4.9     TESTING, TROUBLESHOOTING AND REMEDY

CHAPTER FIVE

• CONCLUSIONS
• RECOMMENDATION

5.3     REFERENCES

 CHAPTER ONE

• INTRODUCTION

In Nigeria today the problems of power outage across phases is so rampant thus leading to some sensitive equipment and appliances being redundant, this could sometimes be the cause of one phase going out with respect to the other.

It may surprise one to note that in an attempt to solve this problems, so many unskilled electricity consumers has  in recent past resorted to some crude means of swapping between phases to obtain power. So many souls have been lost in this act. This is an undesirable condition to consumers and the need now arises to design a device that can automatically select among the phases and make power supply available at the consumers terminal.

However, this can only be possible if one have a three phase met or and there is supply from any of the service line or the entire line, this project known as a three phase automatic phase selector has been constructed with a view of solving the problems stated above. The design and construction was based on the principle of Electro magneto-Dynamism and alignment as demonstrated in the contactor arrangement.

Among other components are the timers miniature-circuit breakers the contactors and indicator bulbs, the ease with which the device is operated is well elaborated to ensure simplicity effort were made to present a stop by step operation of the project. As much as there is no project without limitation and applications, we have as well dedicated a section of this paper to look into it.

In order to ease the effort of technicians in restoring the devices should there be any malfunction associated.

Faults and how they are cleared is presented, however, there are no user serviceable parts in the device therefore all maintenance should be referred to a qualified electrical personnel.

For us to be notified when the power off condition has occurred a power failure signal device is attached to the system. This system indicates when there is power failure through alarm indication. As soon as the system experiences power failure you will receive a signal from an alarm.

Power Outage signal notifies you by alarm when your electrical equipment suffers a power outage. If you have important equipment running and want to know if there has been a power cut while you’re not around, this app can help. From Freezers to Fish Tanks and all things electrical, Power Outage Alarm can provide you with additional peace of mind.

Power failure may be caused by various factors: an overload on the power plant, a thunderstorm, cable breakage during excavations. Whatever the reason you will be notified as soon as the power failure occurred in your remote area and you can act accordingly. This system also will give a notification when the power was restored.

Power Outage Alarm works happily in the background on your Android device and will keep monitoring even when your device is asleep and the screen is off.

1.2                                          OBJECTIVE OF THE PROJECT

The objective of this work is to design a 200A device that will overcome power fluctuation phase interruption by selecting next most healthy available phase to feed the equipment. The power failure alarm triggers a buzzer when the mains supply cuts off. Once the buzzer sound, one will know that there is a loss of power supply and actions need to be taken to rectify the situation by providing alternative power supply or relocating the installation.

1.3                                      SIGNIFICANCE OF THE PROJECT

Industries require three phases power to run their machinery. Some of them require continuous \ uninterrupted power to maintain their data. Auto phase selector unit for those equipment whose supply is single phase. The single phase supply is selected automatically from three phases supply.

Auto Phase Selector introduces an automatic solution to overcome power fluctuation \ phase interruption by selecting next most healthy available phase to feed the equipment.

A power cut may have cut the heater off in the greenhouse, a fan off in a computer room, it may have caused a computer to fail, there are hundreds of reasons that you need to know if there is or has been a power failure. This device is designed to inform you when the power has failed.

1.4                                     STATEMENT OF THE PROBLEMS

In every home, office or industries, automatic phase selector plays a vital role, that is, It provides a means of switching from one phase of AC mains to another in the case of failure in the existing phase; This project has been improved on the existing types of electromechanical device that has being in use over the years.

In the course of designing this project, different kinds of problem was notice such as:

• Difficulty in troubleshooting with circuit without the circuit diagram
• Difficulty in connecting the output without the three phases short-circuiting, until a multiplexing circuit was gotten.
• Difficult in wiring because of the strong wiring the project required..

1.5                            SCOPE AND LIMITATION OF THE PROJECT

This work covers only a three phase automatic phase selector which can only be used for providing a means of switching from one phase of AC mains to another in the case of failure in the existing phase and, which also give indication when power fails in the whole phases.

1.6                                           PURPOSE OF THE PROJECT

The purpose of the project is to provide the supply for the single phase load from the one of the active phase of the 3-phase supply and, which also give indication when power fails in the whole phases.

1.7                                         APPLICATION OF THE PROJECT

Some common examples of entities that implement automatic switches out of necessity are: hospitals, data centers, jails and prisons, fire departments, defense organizations, and police departments.

1.8                                   DEFINITION OF TERMS

CHANGEOVER: Generally, a changeover switch is a system which could be operated manually or automatically , that changes one source of power supply to another source in case of power failure from either of the two sources.

RELAY: relay is one of the major components used in this work which is an electrical device, typically incorporating an electromagnet, which is activated by a current or signal in one circuit to open or close another circuit.

POWER FLUCTUATIONS: is a periodic dip or spikes in the electrical current of any given circuit.

POWER FAILURE: is a short- or long-term loss of the electric power to an area.    

1.9                          PROJECT WORK ORGANIZATION

The various stages involved in the development of this project have been properly put into five chapters to enhance comprehensive and concise reading. In this project thesis, the project is organized sequentially as follows:

Chapter one of this works is on the introduction to changeover switch. In this chapter, the background, significance, objective limitation and problem of changeover switch with phase selector and power failure alarm were discussed.

Chapter two is on literature review of changeover switch. In this chapter, all the literature pertaining to this work was reviewed.

Chapter three is on design methodology. In this chapter all the method involved during the design and construction were discussed.

Chapter four is on testing analysis. All testing that result accurate functionality was analyzed.

Chapter five is on conclusion, recommendation and references.