PLC_Architecture_Professional_Presentation.pdf

Transcript

1. PLC ARCHITECTURE Programmable Logic Controller Industrial Automation Presented by: Mrs.A.R.Magdum
2. 1. Introduction to PLC • PLC stands for Programmable Logic Controller. • It is a digital industrial control system used to automate machines and processes. • PLC executes a stored control program and responds to field inputs. • It provides reliable, flexible and fast control. 2
3. PLC Architecture
4. 3. Central Processing Unit (CPU) • CPU is the brain of the PLC. • Reads input information and executes the user program. • Performs logic, arithmetic, timing and counting operations. • Updates outputs according to the control logic. • Also manages diagnostics and communication. 4
5. 4. Memory Unit • Stores the user program and process data. • Stores input/output status, timer and counter values. • RAM is used for temporary data storage. • ROM / EEPROM / Flash memory stores programs and system information. 5
6. 5. Input Module • Receives signals from sensors and switches. • Converts field signals into signals understood by the PLC CPU. • Digital inputs: push buttons, limit switches and proximity sensors. • Analog inputs: temperature, pressure and level signals. 6
7. 6. Output Module • Receives commands from the CPU. • Controls actuators and other field devices. • Digital outputs control ON/OFF devices such as relays and lamps. • Analog outputs provide variable control for devices such as valves and drives. 7
8. 7. Power Supply • Provides the required electrical power to PLC components. • Converts the available AC supply to suitable DC voltage where required. • Ensures stable and reliable operation of the PLC. • 24 V DC is commonly used for PLC control circuits. 8
9. 8. Communication Interface • Enables communication between the PLC and other automation devices. • Used with HMI, SCADA, other PLCs and industrial computers. • Common networks include Ethernet, Modbus, PROFIBUS and PROFINET. • Supports data exchange, monitoring and supervisory control. 9
10. 9. Programming Device • Used to create, edit, download and monitor PLC programs. • A computer with PLC programming software is commonly used. • Helps in online monitoring, testing and troubleshooting. • Common IEC languages include Ladder Diagram, FBD and Structured Text. 10
11. 10. PLC Scan Cycle 1 INPUT SCAN 2 PROGRAM EXECUTION 3 OUTPUT UPDATE 4 COMMUNICATION & DIAGNOSTICS The PLC continuously repeats this cycle. The complete time is called Scan Time. 11
12. 11. Working of PLC • Sensors detect the condition of the industrial process. • Input module sends the status to the CPU. • CPU executes the stored control program. • Output module sends control signals to actuators. • The machine or process responds, and the cycle repeats continuously. 12
13. 12. Advantages of PLC • High reliability and fast operation. • Reduced wiring compared with relay-based control. • Easy programming, modification and troubleshooting. • Flexible for different industrial applications. • Supports communication, monitoring and expansion. 13
14. 13. Applications of PLC • Manufacturing and assembly lines • Conveyor and material-handling systems • Packaging and bottling machines • Water and wastewater treatment • Robotics and process automation • Traffic and building automation 14
15. 14. Conclusion • PLC is a key technology in modern industrial automation. • Its main architecture includes CPU, memory, input/output modules, power supply and communication. • The scan cycle allows the PLC to continuously monitor inputs and control outputs. • PLC improves reliability, flexibility and efficiency of industrial control. 15
16. THANK YOU Any Questions?