CHAPTER ONE
INTRODUCTION
1.1 BACKGROUND INFORMATION
As
the world becomes concerned with conserving electric power and the fuels that
generate electricity, there is a growing need for the conscientious homeowner
to keep an eye on and minimize their power usage.
Vampire
or standby power is loosely defined as the “electrical power consumed by
appliances while they are switched off (but are designed to draw some power) or
in a standby mode. This only occurs because some devices claimed to be “s
different state from switching off at the pole off at the power point is
effective enough to control the vampire power, there is no need to disconnect
all the devices from the power point.
Some
devices utilize vampire power in a useful manner to provide persistence
features such as maintaining clock settings between active sessions,
convenience features such as powering the necessary hardware to respond to
remote controls, and to eliminate long initialization times by keeping the
hardware in a semi-powered state. Other devices have no beneficial use of
vampire power, such as a powered but disconnected mobile device charger or an
uninterruptible power supply (UPS) with no active system connected.
With
advancement of technology, things are becoming simpler and easier for us.
Automation is the use of control systems and information technologies to reduce
the need for human work in the production of goods and services.
The case of the MICROCONTROLLER TIMER
SOCKET OUTLET helps in conserving the vampire power. Electrical and electronic
appliances are connected to the socket outlet and programmed to be in power for
a specific dur way in conserving energy as the device(s) is/are disconnected
after the specified duration. It is very useful in cases whereby the user has
to keep in touch of what he or she had connected earlier and due to the
multitasking nature of human beings, we tend to forget what had been connected
to attend to other things in the household or wherever we find ourselves.
1.2 AIM AND
OBJECTIVES OF THE PROJECT
The aim of this
project is to design and construct an automatic socket outlet with an
operational timer incorporated into it using a microcontroller. The objectives
of this project are as follows:
1. To conserve electrical power domestically.
2. To reduce and subsequently prevent
electrical hazards in the home front.
3. To control the use of electrical power
domestically.
Through conservation and control of
electrical power, electricity bills are reduced.
1.3 PROJECT MOTIVATION
Since
the advent of socket outlet manufacturing in developing countries like Nigeria,
solution has been found for power conservation or regulation. There is yet to
be an effective socket outlet for timing domestic socket outlets. The failure
to have an operational timer for the socket outlets has caused
a lot of electrical hazards. This has claimed lives and properties of many
people. The user often forgets to look after what he/she had connected and due
to incessant power outages, he/she often forgets to switch off appliances
earlier connected to power when leaving his/her home or due to carelessness of
the user. Due to this negligence, the connected appliances continue to build
up, when power is restored, even after completing their purpose of connection
and when it gets beyond control, it damages the appliances. Repeated
occurrences of these hazards have led to the loss of valuable things worth
millions of naira.
However,
with the help of a timer socket outlet, an effective solution is provided to
these problems. An effective control timer for the socket outlet makes it safer
and easier to use and also helps to reduce hazard rate. The use of a
microcontroller comes to play in this motivation. Every microcontroller has a
timer unit inside. A timer is nothing more than a time counting device
fabricated inside the microcontroller unit. A wide range of practical
applications require a timer in action. For example, we need to turn a motor ON
for 5 minutes and then turn it OFF, how will we do that? A timer inside a
microcontroller unit aids us in implementing this perfectly.
1.4 METHODOLOGY
The
circuit employs the use of various electrical and electronic components like
resistors, capacitors, light emitting diode (LED), switches, piezoelectric
buzzer, 13-amp socket outlet, jumper wires, 7-segment display, battery, relay,
Vero board and most importantly, the Peripheral Interface Microcontroller
16F877 microcontroller (PIC 16F877).
The
microcontroller is programmed using ”softwarethe“MikroC. It is programmed to
communicate with all the other components on the board.
The
switches are used to input instructions into the microcontroller.
The
instructions are basically the SET TIME, START, RESET and STOP.
·
The
SET TIME instructions are displayed on the 7-segment display.
·
The
START button signifies the beginning of the entire timing process.
·
If
a wrong time is set in, the RESET button helps to restore it to default.
·
The
STOP button helps to stop the timing process, this is necessary as there could
be a change of mind after the process has started.
The battery serves as a temporary memory
holder. If during the process, there is power outage and the set instruction
has not been reached, it will help the circuit start from where it stops when
power is restored. For example, a 12,000-litre reservoir fills to the brim in
30minutes, the set instruction will be 30minutes and if there is power outage
after the 23rd minute, the battery helps to continue from where it
stopped (23rd minute) to the 30th minute. However, a
major limitation to this is in the use of a boiling ring, or for the purpose of
boiling. If experimentally, pure water boils in exactly 10mins, and power
outage occurs in the 7th minute for as long as 30minutes, when power
is restored, the water cannot boil in 3minutes again. So this is where the STOP
button comes to play.
The buzzer and the LED serve as audio and
visual indicators respectively. They indicate the completion of the timing
process. They indicate that the process was completed according to the set
instruction. After completion, the circuit automatically shuts the relay off
which stops the supply of power to the circuit thereby conserving power.
The 13-amp socket is used for appliances
with fuses rated 13A and below, examples are phone chargers, television, etc.
The
microcontroller, capacitors, transformer, relay, etc. serve different purposes
which will be discussed in subsequent chapters.