This document presents a project to create an automatic room light controller that can sense when a person enters or exits a room. It will light up the room when someone enters and also count the number of people entering and exiting using infrared sensors and a microcontroller. The system is designed to save electricity by turning lights off when no motion is detected. It includes a block diagram, descriptions of the power supply, sensors, microcontroller, relay, and advantages like energy savings and easy operation. Potential disadvantages are an inability to detect multiple people at once or control lights manually from inside the room.

1. A
PRESENTATION
AUTOMATIC-ROOM-LIGHT-CONTROLLER-WITH-
BIDIRECTIONAL-VISITOR-COUNTER-
BY VIVEK KUMAR KUSHWAHA

2. A presentation on
ENERGY SAVING SYSTEM
Under the supervision of
Mr. P. N. Verma
(Assistant Professor, EED)
Submitted to
Department of Electrical
Engineering
Submitted by:
Vivek Kumar kushwaha(1473520910)
Sudhir Kumar Tiwari(1373520049)
Ravi Kumar((1473520906)
Vikas(1373520052)

3. CONTENTS
 Objective of the work.
 Introduction.
 Working.
 Block Diagram.
 Power Supply.
 Enter and Exit circuit.
 Transmission Circuit.
 Receiver circuit.
 Microcontroller.
 Relay Circuit.
 Advantages and Disadvantages.

4. Objective of the work:
The aim of our project is to make a controller
which can sense if any person enters the room
and it lights up the room automatically and also
counts how many person are entering the room
or going out of it. It is made to unwanted
prevent electric power waste in schools,
colleges, offices and houses. This whole process
is operated totally automatically by its sensors.

5. Introduction
 Usually when a person enters the room in darkness, we
find it difficult to locate the wall-mounted switch board
to switch “on” the light.
 For a stranger it is tougher still as he has no knowledge
of the correct switch to be turned on.
 Here is our reliable circuit that takes over the task of
switching “on” and switching “off” the light
automatically when somebody enters or leaves the room
during darkness. The circuit has following salient
features:

6. Working:

7. BLOCK DIAGRAM

8. BLOCK DIAGRAM DESCRIPTION:-
 Power Supply
Here we used +12V and +5V dc power supply.
The main function of this block is to provide the
required amount of voltage to essential
circuits. +12 voltage is given. +12V is given to
relay driver. To get the +5V dc power supply
we have used here IC 7805, which provides
the +5V dc regulated power supply.

9. Enter and Exit Circuits:-
There are two main parts of the circuits.
 Transmission Circuits (Infrared LEDs)
 Receiver Circuit

10. Transmission Circuit:
IR Transmitter: We have
implemented the Person counter
module using 2 transmitters and 2
receivers. We have used Infra-Red
transmitters. Reason behind
choosing IR LED is, infrared beams
are not visible to human eyes and
they are not easily triggered by other
sources in the environment.
Transmitters used are IR LEDs.

11. RECEIVER :-
We have used IR sensor as an Infrared receiver. It
is an active low device, which means it gives low
output when it receives the Infrared rays. So when
the IR rays are interrupted by any person then
microcontroller will receive a high pulse from the IR
receiver.

12. A microcontroller is device, which contains all the
device necessary to form working system, in a single
chip. Therefore, inside the microcontroller we find a
central processing unit (CPU), program memory, data
memory, I/O ports, serial communication interface.
MICROCONTROLLER(AT89S52)

13. A single pole dabble throw (SPDT) relay is connected
to port RB1 of the microcontroller through a driver
transistor. The relay requires 9 volts at a current of
around 100ma, which cannot provide by the
microcontroller. So the driver transistor is added.
RELAY CIRCUIT:

14. Light emitting diodes are diodes (electronic components that let
electricity pass in only one direction) that emit visible light when
electricity is applied, much like a light bulb. When many LEDs are
side-by-side, they can create pictures, such as the scrolling red
LED signs found everywhere
PHOTO DIODE:- The Photo diode have two terminals for Vcc
(Anode) (+5v), ground(cathode). In the normal state.
It receive light from the IR transmitter and it will act like a closed
switch. So the entire voltage will go to the ground
Whenever the object (or) obstacle come between the IR transmitter
and Photo diode at the time Photo diode will act as a open switch
The entire voltage will go to inverting terminal of op-amp
LED (light emitting diode):-

15. Circuit
Diagram:

16. Low cost
Easy to use
Can be used for counting purposes
Can be used for automatic room light control
The Most advantage is that it will help to save electricity.
When no one is there in room the appliances will be off.
Advantage

17. Disadvantages
• It is used only when one person cuts the rays of
the sensor hence cannot be used when two or more
persons cross the door simultaneously.
• When anybody is inside the room and we need to switch
off the power then we’ve to do it manually. So, in this
case we fail to automatically control the light.
• In seven segment display board we can count up to a
certain no of people entering into the room. If the no of
body entering the room is greater than the maximum
limit of the display board then we fail to count it.