Case

Industrial Automation Project：Automated Packaging Line in a Bakery Factory

I. Core Applications of PLC in Industrial Automation

1. Production Process Control
   Logic Control: Replaces traditional relays to enable automated sequential control (e.g., assembly line start/stop, workstation switching).
   Motion Control: Coordinates servo and stepper motors for precise positioning (e.g., CNC machines, robotic trajectory control).
   Process Control: Regulates parameters such as temperature, pressure, and flow rate (e.g., injection molding machines, heat treatment furnaces).
2. Machine-Level Automation
   Standalone Equipment Control: Independently operates stamping machines, packaging machines, sorting systems, etc.
   Safety Interlocks: Emergency stop (E-Stop), light curtain protection, safety door monitoring (compliant with ISO 13849).

3.Production Line Coordination
Multi-Equipment Synchronization: Coordinates conveyors, robotic arms, and inspection devices via industrial buses (e.g., Profinet, EtherCAT).
Flexible Manufacturing: Rapid production recipe switching (e.g., product specification changes in food processing).

4. Data Acquisition & Monitoring
   Real-Time Data Reporting: Transmits equipment status (current, vibration) to SCADA/MES systems.
   Fault Prediction: Triggers alerts based on threshold values (e.g., motor overload).
   II. Core Functions of PLC
5. The “Brain” of Industrial Control

• Executes deterministic control (μs-level response), ensuring precise production timing.

4. High Reliability Assurance

• No mechanical contacts, lifespan exceeding 100,000 hours (far surpassing relays).

4. Adaptability to Changing Needs

• Logic modifications via programming without rewiring (e.g., process adjustments).

4. Standardized Interfaces

• Supports industrial communication protocols (Modbus TCP, OPC UA) for seamless device integration.

III. Key Impacts of PLC on Industrial Automation

1. Revolutionizing Production Efficiency

• Automotive welding lines: PLC reduce cycle time from 60s to 30s.

1. Enhanced Quality Consistency

• Eliminates human error (e.g., tightening torque accuracy within ±1%).

1. Cost Optimization

• Reduces relay cabinet space and maintenance costs by over 70%.

1. Enabling Smart Manufacturing

• Provides real-time data for digital twins (e.g., equipment status mapping).
  IV. Future Trends in Industrial Automation
• Edge Computing: PLCs locally run AI-based quality inspection models (e.g., defect detection).
• IT/OT Convergence: Tools like TIA Portal enable PLC-Python script interaction.

PLC serve as the cornerstone of industrial automation, with their evolution directly shaping the advancement of smart manufacturing.