ABSTRACT
 The uninterrupted power supply (UPS) is design to help in the offices, workshops and house hold appliances, due to the unstable power supply being supplied by (NEPA) presently known as Power Holding Company of Nigeria (PHCN) usually supply to us.
 
 With the help of the UPS we don't need to depend much on PHCN it is stress free because it don't need someone to change it over when light goes off, once there is any power failure it will automatically switched on and when power comes it will switch off and start charging the battery.
 
 Another interesting thing in the UPS is that it does not need any external charger for charging the battery when it goes low, it have already built charger inside the UPS when there is light it will be charging the battery. 
 
 
 TABLE OF CONTENTS
 COVER PAGE
 TITLE PAGE
 APPROVAL PAGE
 DEDICATION
 ACKNOWLEDGEMENT
 ABSTRACT
 TABLE OF CONTENTS
 
 CHAPTER ONE
 INTRODUCTION
 INVERTER SECTION/OSCILLATION
 AUTOMATIC CONTROL SECTION
 AIM OF THE DESIGN
 
 CHAPTER TWO
 DEFINITION OF TERMS/COMPONENTS DESCRIPTION
 RESISTORS
 CAPACITORS
 TRANSISTORS
 FIELD EFFECT TRANSISTORS
 RELAYS
 DIODE
 TRANSFORMER
 
 CHAPTER THREE
 SECTIONAL DESCRIPTION FOR THE SYSTEM
 OSCILLATION CIRCUIT SECTION
 CIRCUIT OPERATION
 WAVEFORM OF AN OSCILLATION
 WAVEFORM OF AN INVERTER
 SWITCHING CIRCUIT SECTION
 POWER TRANSFORMER AND INVERTER ACTION
 PRECAUTION DURING WINDING OF TRANSFORMER
 AUTOMATIC CIRCUIT SECTION/CHARGER
 COMPLETE CIRCUIT DIAGRAM OF THE UPS
 
 CHAPTER FOUR
 CONSTRUCTION PROCEDURE AND TESTING
 CASING AND PACKAGING
 ASSEMBLING OF SECTIONS
 TESTING OF SYSTEM OPERATION
 
 CHAPTER FIVE
 PROBLEMS ENCOUNTERED, CONCLUSION AND RECOMMENDATION
 PROBLEMS ENCOUNTERED
 RECOMMENDATION
 
 CHAPTER SIX
 COST ANALYSIS
 REFERENCES