The document outlines the design and implementation of an automatic changeover system using a programmable logic controller (PLC) to address the challenges posed by manual transfer switches during power outages. It describes the system's objectives, which include automating the switching process between generator power and main power, thereby reducing downtime. The proposed system utilizes PLC programming to efficiently manage the operation of the changeover process.

1. DESIGN AND IMPLEMENTATION OF
AUTOMATIC CHANGE OVER USING PLC
Candidates
MOHAMED RIYASUDEEN D (Reg.No: 912816105013)
KARTHIKEYAN M (Reg.No: 912816105301)
MOHAMED SAYEED ANWAR J (Reg.No: 912816105015)
ARAVINTH A (Reg.No: 912816105003)
Supervisor
M Paul Jeyaraj
Asst. Professor & Dept. of EEE
Syed Ammal Engineering College, Ramanathapuram

2. Overview
• Introduction about project
• Problem Definition
• Objective
• Existing Systems
• Proposed System
• Block Diagram
• Principle of Operation of the Proposed System
• Working of the Proposed System.
2

3. Introduction
• The automatic changeover system mainly reduces the problem
regarding manual switching.
• This project can be represented by the construction and design of
PLC based auto-changeover system.
• The world is increasingly demanding for automation through PLC.
It is the main strike in our mind.
• For the controlling, monitoring and integrating system, PLC is a
very efficient tool to automate.
• PLC can withstand in any situation like temperature, humidity,
noise, and moisture.
3

4. Problem Definition
1. When the power goes out, everything will go dark if we
have a manual transfer switch. We would need to grab our
flashlight and go out to the generator to start it manually
and connect it to the transfer switch.
2. When utility power comes back on, we need to manually
switch the power back to the EB line and turn off the
generator.
3. This process takes more time to bring back the backup
power supply from the generator.
4

5. Objective
1. To automatically switch on the generator and to switch over
the load to the generator whenever there is a power failure in
the mains.
2. To automatically switch over to mains once the power supply
is restored from the mains and simultaneously switches off
the generator.
3. To reduce the time taken to switching over the supply from
the generator as well as from the mains.
5

6. Existing System
6
 Changeover Switches, also called Double Throw Switches, are
available with OFF and without OFF.
 These are used to operate two different circuits, with different
number of inputs and outputs. Changeover Switches without
jumpers (potential free contacts) are used to connect two different
circuits from two different sources, with two different operating
voltages or any other incompatible lines.
 All contacts by default are “Break Before Make” (BBM) type
to avoid overlapping of different circuits while overlapping
changeover contacts. “Make Before Break” (MBB) type are
offered against specific requirements.

7. Proposed System
 As the name implies, everything is automatic with this type of
transfer switch.
 The power may go out for a second or two, but the transfer
switch senses this and automatically signals our generator to
start up.
 Then the transfer switch connects our home or business to the
generator.
 When EB power comes back on, the transfer switch
disconnects the power supply from the generator and shuts the
generator back off until the next power outage occurs.
7

8. Block Diagram of the Proposed System
8

9. Principle of Operation of the Proposed System
 The world is increasingly demanding for automation through
PLC. It is the main strike in our mind. For the controlling,
monitoring and integrating system, PLC is a very efficient tool
to automate.
 PLC can withstand in any situation like temperature, humidity,
noise, and moisture. For controlling and handling PLC there is
no need to be an expert, it can be operated easily.
 The proposed system uses a Programmable Logic Controller
(PLC) and it is programmed based on the operation to be
performed.
 The programming is done using the standard PLC software
such as WPL, OMRON, etc,.., through ladder diagram.
9

10. Working of the Proposed System
10
 In case of mains power failure, this switch turns ON the
generator automatically and connects the load to the generator
output.
 It switches OFF the generator automatically when power
is restored and returns the load to the mains power with the help
of the desired range of parameters which may be set by
programming.
 This helps in reducing the time consumption required for
switching operations. In this way, the continuity of supply is
maintained.

11. Implementation Plan
• Our project is just a prototype, so we are using ordinary supply
from one side considered as a generator supply.
• The main supply is drawn from other side which is considered
as a EB supply.
• We are using a Programmable Logic Controller (PLC) to
implement the automatic change over through relays.
• The programming of the PLC is in the form of ladder diagram.
It consists of Timers, NCs and NOs based on the operation to
be performed.
• The timer used is to include some delays so that the PLC can
check for the detection of supply at that delay for change over.
11

12. THANK YOU
12