This is a small project on Siemens PLC Step 7 models. The project required lot of lateral thinking and logical decision making in order to develop programs for the traffic light management for the entire chandigarh city. The project is known as Total Traffic Security & Management (TTSM)
5. Implementation Environment
Software Used
1. MicroWin version 4.0
2. Simatic Manager 5.4
3. PLC Simulator
Hardware Used
1. Operating System i.e. Computer with windows XP
professionals sp2
2. PLC trainer kit
3. PLC ( S7-200/300)
4. PROFIBUS
5. MPI/PPI
6. Expansion Modules
6. Laboratory at IATC
Automation
AC / DC Drives
Switchgears
Industrial Hydraulics/Pneumatics
CNC Centre
Computer Centre
Machine Shop
7. Automation Lab
PLC Hardware Configuration
PLC Program development
S7 300 PLC training kits
S7 200 PLC training kits
8. Industrial Automation
Automation is encompassing virtually every
walk of life.
Automation solutions are required right from
agricultural to space technology.
Plant Automation is the necessity for the
manufacturing industry to survive in today’s
globally competitive market
9. What is Automation ?
Automation is basically the delegation of human control
function to technical equipment for
•Increasing Productivity
• Increasing Quality
• Reducing Cost
• Increasing Safety in working conditions
10. History of Automation
Pneumatic Control
Hard wired logic Control
Electronic Control using Logic Gates
Programmable Logic Controller
Manual Control
11. Manual Control
All the actions related to process control are taken by the
operators
Drawbacks
Likely human errors and consequently its effect on quality of final product
The production, safety, energy consumption and usage of raw material are all
subject to the correctness and accuracy of human action.
12. Pneumatic Control
Industrial automation, with its machine and process control, had its origin in the
1920s with the advent of "Pneumatic Controllers".
Actions were controlled by a simple manipulation of pneumatic valves, which in turn
were controlled by relays and switches.
Drawbacks
• Bulky and Complex System
• Involves lot of rework to implement control logic
• Longer project time
13. Hard wired logic control
The contactor and Relays together with hardware timers and
counters were used in achieving the desired level of automation
Drawbacks
• Bulky panels
• Complex wiring
• Longer project time
• Difficult maintenance and troubleshooting
14. Electronic Control using Logic Gates
In 1960s with the advent of electronics, the logic gates started
replacing the relays and auxiliary contactors in the control
circuits.
The hardware timers & counters were replaced by electronic
timers
Advantages
Drawbacks
•Reduced space requirements
•Energy saving
•Less maintenance & greater reliability
•Changes in control logic not possible
•More project time
15. Programmable Logic Controllers
In 1970s with the coming of microprocessors and associated peripheral
chips, the whole process of control and automation underwent a radical
change.
Instead of achieving the desired control or automation through physical
wiring of control devices, in PLC it is achieved through a program or say
software.
The programmable controllers have in recent years experienced an
unprecedented growth as universal element in Industrial Automation.
It can be effectively used in applications ranging from simple control like
replacing small number of relays to complex automation problems
16. Advantages of PLCs
Reduced space
Energy saving
Ease of maintenance
Economical
Greater life & reliability
Tremendous flexibility
Shorter project time
Easier storage, archiving and documentation
Fast and Less time consuming
More accurate
Ability to pass heritage
Reduces complexity of tasks
18. The PLC is programmed interface between the field I/p
element like limit switches, sensors, push button and
the final control elements like actuator,
solenoid/control valves, drives, hooters etc
PLC consist of :
Input Module
CPU with Processor and Program memory
Output module
Bus System
Power Supply
20. Central Processing Unit
It is a micro-controller based circuitry. The CPU consists of
following blocks :
Arithmetic Logic Unit (ALU)
Process image memory (Internal memory of CPU)
Internal timers and counters
Program memory
CPU performs the task necessary to fulfill the PLC functions. These
tasks include Scanning, I/O bus traffic control, Program execution,
Peripheral and External device communication, special functions
or data handling execution and self diagnostics.
Programmable Logic Controllers
21. Input module
These modules act as interface between real-time status of
process variable and the CPU.
Analog input module : Typical input to these modules is
4-20 mA, 0-10 V
Ex : Pressure, Flow, Level Tx, RTD (Ohm), Thermocouple
(mV)
Digital input module : Typical input to these modules is 24 V
DC, 115 V AC, 230 V AC
Ex. : Switches, Pushbuttons, Relays, pump valve on off status
Programmable Logic Controllers
22. Output module
These modules act as link between the CPU and the output
devices in the field.
Analog output module : Typical output from these modules is
4-20 mA, 0-10 V
Ex : Control Valve, Speed, Vibration
Digital output module : Typical output from these modules is
24 V DC, 115 V AC, 230 V AC
Ex. : Solenoid Valves, lamps, Actuators, dampers, Pump valve
on off control
Programmable Logic Controllers
23. Power Supply
The power supply gives the voltage required for electronics
module (I/O Logic signals, CPU, memory unit and
peripheral devices) of the PLC from the line supply.
The power supply provides isolation necessary to protect
the solid state devices from most high voltage line spikes.
As I/O is expanded, some PLC may require additional
power supplies in order to maintain proper power levels.
Programmable Logic Controllers
24. Bus System
It is path for the transmission of the signal . Bus system is
responsible for the signal exchange between processor and
I/O modules
The bus system comprise of several single line i.e. wires /
tracks
Programmable Logic Controllers
27. PPI Connection
Mode SelectorMemory Card
Status Indicators
S7-200: CPU Design
Q0
.0 .1 .2 .3 .4 .5 .6 .7
Q1
.0 .1
I0
.0 .1 .2 .3 .4 .5 .6 .7
I1
.0 .1 .2 .3 .4 .5
CPU
224
SIEMENS
SF
RUN
STOP
Potentiometer
Status Indicators for integrated DO
Status indicators for integreted DI
29. Difference b/w S7- 200 & 300
FIELDs S7-200 S7- 300
No. of I/Os 16 byte i.e. 128 128 bytes i.e. 1024
No. of Expansion / signal
Modules
7 Modules 32- 4x Modules
Racking & Mounting Not Available Available up to 8 racks
i.e. 0 to 7
Internal Memory 32 byte 128 byte
Scope less range of operation Medium Scale of
operation
Scan time 3 ms 2 us
Simulator Not Available Available as PLCSim
Software Used MicroWin Simatic Manager
30. 1. Simatic s7-300 is easy to use.
2. S7-300 is fast and powerful.
3. S7-300 is multi faceted and flexible.
4. S7-300 has fast and powerful CPU’s.
5. Simatic configuration and programming software is
very easy.
6. S7-300 use in extremely harsh environment.
7. Its Baud rate is much higher i.e. 192.6 kbps
8. It uses MPI for its Data transfer.
31. 1. Ladder Language (LAD)
2. Function Block Diagram (FBD)
3. Statement List (STL)
32. • In Industry, there are many production tasks which are of
highly repetitive nature.
• Eliminating the possibilities of human error.
• Some of the capabilities of PLC are as follow:
* logic control
* timing,counting,comparison
* analog value processing and PID control
* real time clock
* coordination and communication
• In short, wherever sequential logic control and
automation is desired ,the PLCs are best suited to meet the task.
• Few examples of industries : Tyre industry,steel plant, brick molding,
dairy automation, Printing industry etc.
34. Instruction Set used in
the TTSM System
TTSM
STANDARD
CONTACTS
STANDARD
OUTPUTS
TIMER
COMPARE BYTE
INSTRUCTIONS
35. CONSTRAINTS OF THE PROJECT
1. SHOULD PROVIDE TRAFFIC MANAGEMENT TO THE CITY FROM
ONE CONTROL ROOM.
2. SHOULD PROVIDE COORDINATED TRAFFIC LIGHTS .
3. THE CAMERAS CONNECTED MUST NOT ONLY BE USED FOR
TRAFFIC MANAGEMENT BUT ALSO FOR SECURITY PURPOSES.
4. THE TRAFFIC CONTROLLER MUST BE ABLE TO GIVE PASS TO
EMERGENCY VEHICLES EVEN IF THEY GET RED LEGHT AT THE
TRAFFIC LIGHTS WITHOUT DISTURBING THE COORDINATED
SYSTEM.
5. MAINTENANCE OF THE WHOLE SYSTEM SHOULD BE EASY.