Design And Construction Electric Kettle With Control Switch

ABSTRACT

This project is titled the design and construction of an Electric Kettle with control kettle. It is designed to meet up with the safety and accuracy demand of electric kettle usage in industries and homes in the absence of the user or operator.

It is designed to control the temperature of the electric kettle to a variable range (0°C -100°C) which must be set by the user or operator. And this can be achieved by the use of temperature sensor known as THERMISTOR which functions as a control switch. This thermistor is a temperature control device with a high or low resistance value which can go high or low when the temperature is increased or reduced depending on the type.

 In this project, 100°C is used as a set temperature. And this device is design in such a way that when the temperature of the liquid inside the kettle is reached, the heater of the device will automatically switched-off and will maintain the off stage until when the temperature the liquid is dropped 97°C, and then it will switch-ON again in other to maintain that 100°C. And this automatic feature is controlled by a high current relay.

TABLE OF CONTENT

Title Page

Approval Page

Dedication

Acknowledgement

Abstract

Table of Content

CHAPTER ONE

1.0     Introduction

1.1     Block Diagram of the Electric Kettle with control switch

1.2     Control System

1.3     Circuit Diagram of the System

CHAPTER TWO

2.0     Major Component’s Description

2.1     Resistors

2.2     Diodes

2.3     Capacitors

2.4     Transformers

2.5     Transistor

2.6     Integrated Circuit

2.7     Thermistor

CHAPTER THREE

3.0     Sectional Description of the System

3.1     Comparator Section

3.2     Switching (relay) Section

3.3     Power supply

3.4     Sensor

3.5    circuit operation

CHAPTER FOUR

4.0     Construction Procedure and Testing

4.1     Casing and Packaging

4.2     Assembling of Sections

4.3     Testing of System Operation

CHAPTER FIVE

5.0     Installation of the Completed System

5.1     Problem Encountered

5.2     Cost Analysis

CHAPTER SIX

6.0     Conclusion

6.1     Recommendation

6.2     Bibliography

CHAPTER ONE

1.0     INTRODUCTION

The idea behind the design and construction of this system is to make available or alternative means providing safety and accuracy demand for Electric Kettle users for household or industrial purpose. This goes a long way in helping to curb the problem frequently encountered as a result of fire out break and inaccuracy found in measuring and maintaining temperature. That not with standing it makes it possible to have other means of boiling our liquid without constant temperature monitoring until when the required temperature will be achieved. Thereby creating time for the operator to be engaged on other works while the system is in operation.

Moreover, rate of fire accident cause by heating appliances in this country is high. So there is every need that other means of safety should be made available for constant running of our electric equipments and gadgets and also to provide comfort to man. Hence, with the help of a Thermistor Controlled Electric kettle, which has come to solve the problem of fire accident and inaccuracy found in temperature measurement in Nigeria, a steady running and operation of our electric equipments and gadgets is guaranteed.

1.1    BLOCK DIAGRAM OF TEMPERATURE CONTROL ELECTRIC KETTLE.

The block diagram is as below:

POWER SUPPLY UNIT         COMPACTOR UNIT                  TWITCHING UNIT

SENSOR

1.3     CONTROL SYSTEM

The Temperature control switch system was built to control the temperature of an electric kettle to a specific temperature range with help of a voltage comparator IC.

This system also consists of three stages, that is, power supply stage, comparator and switching stage. This three stages work together in other to give out a specific output –control temperature.

In the power supply unit, 12V supply was used and an integrated circuit, IC, which is capable of comparing two different voltages, while at the switching unit a   relay with a high current is used. This is well explained in detail in chapter three below.

When this system is powered from the 12v DC supply, the comparator will be powered which was configured to generate a current that will be able to drive the relay which is the switching circuit that triggers the kettle.