2. Welcome
The purpose of this Presentation is to
give you a very simple look
Programmable Logic Controllers and its
programming using Ladder Logic.
There is no need for you to be
familiar in any way with this field.
The only requirement is that you
enter with an open mind.
4. Stage 1
AUTOMATION :
Allocation of Human control sequence to
an technical equipment is called Automation.
Egs : Tank Level Maintatinance
5. Automation is the use of machines, control systems and information
technologies to monitor and control the production.
Automation is the use of machines, control systems and information
technologies to monitor and control the production.
In other words, an automated system is any system
that require minimum or no human intervention.
14. TYPES OF AUTOMATION
Building automation
Example: lifts, smoke detectors
Office automation
Example: printers, city cameras
Scientific automation
Example: rocket launching
Light automation
Example: street solar lightening
Industrial automation
Example: automated bottle filling stations , steel factories etc
15. INDUSTRIAL AUTOMATION
The use of Computerized or robotic devices to
complete manufacturing tasks.
PLANT
FIELD
INSTRUMENT
CONTROL SYSTEM
HARDWARE
CONTROL
SOFTWARE
CONTROL
16. So we can imply that with
Industrial control,
factory automation,
and PLC
(if are done well),
we can save a lot of time,
materials, energy, and money.
18. Let’s recall the story of an
explorer in Africa who asked
the native tribesman,
19. How does one eat a huge animal like an
elephant?"
The tribesman looked at the explorer in
astonishment and replied, "We eat it just like
everything else, one bite at a time."
20. Simple as it is, industrial control
is comprised of many smaller
circuits. By exploring and
learning simple smaller circuits,
you can learn to build a complete
automated system.
22. a small computer with a built-in operating system
which monitor inputs and other variable values,
make decisions based on a stored program, and
control outputs to automate a process or machine.
Programmable logic controllers
What is
23. Well, that was simple isn’t it ?
Lets put it in another way..
24. PLC(PROGRAMMABLE LOGIC CONTROLLER)
Programmable Logic Controller (PLC) is an industrial computer
that monitors inputs, makes decisions based on its program and
controls outputs to automate a process or machine.
The automation of many different processes, such as controlling
machines or factory assembly lines, is done through the use of small
computers called a programmable logic controllers (PLCs).
25. WHY PLC?
To reduce human efforts .
To get maximum efficiency from machine and control them with
human logic .
To reduce complex circuitry of entire system .
To eliminate the high costs associated with inflexible, relay-controlled
systems.
26. UNDERSTANDING OF PLC (Example )
Machine can be controlled by PLC without human efforts
27. A PLC is similar to a computer which is designed to
be programmed once, and run repeatedly as
needed.
29. MAJOR COMPONENTS OF A PLC
PROCESSOR
POWER
SUPPLY
I M
N O
P D
U U
T L
E
O M
U O
T D
P U
U L
T E
PROGRAMMING
DEVICE
From
SENSORS
Pushbuttons,
contacts,
limit switches,
etc.
To
OUTPUT
Solenoids,
contactors,
alarms
etc.
31. CentralProcessor Unit (CPU)
microprocessor system that contains the system
memory and its decision making unit very similar to
that of a computer’s CPU.
Input Modules
Senses the input signal, isolates it and converts it to
DC level.
32. Output Module
receives the convert control signals from the CPU and
them converts them into digital or analog values that
can be used to control various output devices.
CentralProcessor Unit (CPU)
microprocessor system that contains the system
memory and its decision making unit very similar to
that of a computer’s CPU.
Input Modules
Senses the input signal, isolates it and converts it to
DC level.
33. Programming Device
Personal computer or a Laptop
And Communication Cable
Output Module
receives the convert control signals from the CPU and
them converts them into digital or analog values that
can be used to control various output devices.
CentralProcessor Unit (CPU)
microprocessor system that contains the system
memory and its decision making unit very similar to
that of a computer’s CPU.
Input Modules
Senses the input signal, isolates it and converts it to
DC level.
39. The first and still most popular
programming language used
with PLC is Ladder Logic
Programming (LAD).
40. They are called "ladder" diagrams
because they resemble a ladder,
with two vertical rails (supply
power) and as many "rungs"
(horizontal lines).
The first and still most popular
programming language used
with PLC is Ladder Logic
Programming (LAD).
41. Basic Ladder Logic Symbols
Normally Open (NO) contact
Passes power (on) when coil driving the contact is on.
Contacts
42. Normally Closed (NC) contact
Passes power (on) when coil driving the contact is off.
Basic Ladder Logic Symbols
Normally Open (NO) contact
Passes power (on) when coil driving the contact is on.
Contacts
43. Output or Coil
When power flows through the Coils via contacts they are
energized.
Basic Ladder Logic Symbols