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Intermediate20 min readManufacturing

Inovance Sequential Function Charts (SFC) for Assembly Lines

Learn Sequential Function Charts (SFC) programming for Assembly Lines using Inovance InoProShop / AutoShop. Includes code examples, best practices, and step-by-step implementation guide for Manufacturing applications.

πŸ’»
Platform
InoProShop / AutoShop
πŸ“Š
Complexity
Intermediate to Advanced
⏱️
Project Duration
4-8 weeks

Optimizing Sequential Function Charts (SFC) performance for Assembly Lines applications in Inovance's InoProShop / AutoShop requires understanding both the platform's capabilities and the specific demands of Manufacturing. This guide focuses on proven optimization techniques that deliver measurable improvements in cycle time, reliability, and system responsiveness.

Inovance's InoProShop / AutoShop offers powerful tools for Sequential Function Charts (SFC) programming, particularly when targeting intermediate to advanced applications like Assembly Lines. With ~2% global, top-3 in China market share and extensive deployment in industrial automation, Inovance has refined its platform based on real-world performance requirements from thousands of installations.

Performance considerations for Assembly Lines systems extend beyond basic functionality. Critical factors include 5 sensor types requiring fast scan times, 5 actuators demanding precise timing, and the need to handle cycle time optimization. The Sequential Function Charts (SFC) approach addresses these requirements through perfect for sequential processes, enabling scan times that meet even demanding Manufacturing applications.

This guide dives deep into optimization strategies including memory management, execution order optimization, Sequential Function Charts (SFC)-specific performance tuning, and Inovance-specific features that accelerate Assembly Lines applications. You'll learn techniques used by experienced Inovance programmers to achieve maximum performance while maintaining code clarity and maintainability.

Inovance InoProShop / AutoShop for Assembly Lines

Inovance ships InoProShop as its primary programming IDE for the AM600 / AM610 / H5U medium-PLC families and AutoShop for the Easy-series compact PLCs. InoProShop is built on the CODESYS 3.5 platform, which means engineers transferring from Beckhoff TwinCAT, WAGO e!Cockpit, or Schneider EcoStruxure Machine Expert will recognise the project tree, IEC 61131-3 editors, and visualisation tools immediately. AutoShop is a more traditional ladder-and-IL editor closer to compact-PLC tradition. Inovance'...

Platform Strengths for Assembly Lines:

  • CODESYS-based InoProShop for IEC 61131-3 compliance

  • Tight integration with Inovance servo drives and inverters

  • Strong motion, robotics, and elevator-control product lines

  • EtherCAT support across mid-tier and high-end CPUs


Unique ${brand.software} Features:

  • InoProShop built on CODESYS 3.5 β€” full IEC 61131-3 compliance

  • Native EtherCAT motion across mid-tier and high-end CPUs

  • Tight integration with Inovance servo drives, inverters, and HMIs

  • AutoShop for compact AC800 / Easy-series CPUs (lighter IDE)


Key Capabilities:

The InoProShop / AutoShop environment excels at Assembly Lines applications through its codesys-based inoproshop for iec 61131-3 compliance. This is particularly valuable when working with the 5 sensor types typically found in Assembly Lines systems, including Vision systems, Proximity sensors, Force sensors.

Control Equipment for Assembly Lines:

  • Assembly workstations with fixtures

  • Pallet transfer systems

  • Automated guided vehicles (AGVs)

  • Collaborative robots (cobots)


Inovance's controller families for Assembly Lines include:

  • AM600: Suitable for intermediate to advanced Assembly Lines applications

  • AM610: Suitable for intermediate to advanced Assembly Lines applications

  • H5U: Suitable for intermediate to advanced Assembly Lines applications

  • AC800: Suitable for intermediate to advanced Assembly Lines applications

Hardware Selection Guidance:

Inovance CPU choice ranges from Easy320 / Easy510 (compact, AutoShop-programmed, FX-style memory model) through AC800 (mid-range compact) to AM600 / AM610 / H5U (medium PLC with EtherCAT, OPC UA, redundant networking on H5U). AM600 is the volume product for OEM machinery; H5U is the choice for higher-axis-count motion applications and lithium-battery / EV manufacturing lines where EtherCAT and tig...

Industry Recognition:

High in China across textiles, packaging, lithium battery, EV manufacturing, elevators, robotics; growing in SE Asia and MEA. High in Chinese EV manufacturing β€” Inovance is a major automation supplier to BYD, NIO, and Tier 2/3 EV-component plants. AM600 + H5U with EtherCAT motion controls battery-cell assembly, module welding, pack assembly, and end-of-line test stations. Less common in Western Tier 1 automotive but appear...

Investment Considerations:

With $$ pricing, Inovance positions itself in the mid-range segment. For Assembly Lines projects requiring advanced skill levels and 4-8 weeks development time, the total investment includes hardware, software licensing, training, and ongoing support.

Understanding Sequential Function Charts (SFC) for Assembly Lines

Sequential Function Chart (SFC) is a graphical language for programming sequential processes. It models systems as a series of steps connected by transitions, ideal for batch processes and machine sequences.

Execution Model:

Only active steps execute their actions. Transitions define conditions for moving between steps. Multiple steps can be active simultaneously in parallel branches.

Core Advantages for Assembly Lines:

  • Perfect for sequential processes: Critical for Assembly Lines when handling intermediate to advanced control logic

  • Clear visualization of process flow: Critical for Assembly Lines when handling intermediate to advanced control logic

  • Easy to understand process steps: Critical for Assembly Lines when handling intermediate to advanced control logic

  • Good for batch operations: Critical for Assembly Lines when handling intermediate to advanced control logic

  • Simplifies complex sequences: Critical for Assembly Lines when handling intermediate to advanced control logic


Why Sequential Function Charts (SFC) Fits Assembly Lines:

Assembly Lines systems in Manufacturing typically involve:

  • Sensors: Part presence sensors for component verification, Proximity sensors for fixture and tooling position, Torque sensors for fastener verification

  • Actuators: Pneumatic clamps and fixtures, Electric torque tools with controllers, Pick-and-place mechanisms

  • Complexity: Intermediate to Advanced with challenges including Balancing work content across stations for consistent cycle time


Programming Fundamentals in Sequential Function Charts (SFC):

Steps:
- initialStep: Double-bordered box - starting point of sequence, active on program start
- normalStep: Single-bordered box - becomes active when preceding transition fires
- actions: Associated code that executes while step is active

Transitions:
- condition: Boolean expression that must be TRUE to advance
- firing: Transition fires when preceding step is active AND condition is TRUE
- priority: In selective branches, transitions are evaluated in defined order

ActionQualifiers:
- N: Non-stored - executes while step is active
- S: Set - sets output TRUE on step entry, remains TRUE
- R: Reset - sets output FALSE on step entry

Best Practices for Sequential Function Charts (SFC):

  • Start with a clear process flow diagram before implementing SFC

  • Use descriptive step names indicating what happens (e.g., Filling, Heating)

  • Keep transition conditions simple - complex logic goes in action code

  • Implement timeout transitions to prevent stuck sequences

  • Always provide a path back to initial step for reset/restart


Common Mistakes to Avoid:

  • Forgetting to include stop/abort transitions for emergency handling

  • Creating deadlocks where no transition can fire

  • Not handling the case where transition conditions never become TRUE

  • Using S (Set) actions without corresponding R (Reset) actions


Typical Applications:

1. Bottle filling: Directly applicable to Assembly Lines
2. Assembly sequences: Related control patterns
3. Material handling: Related control patterns
4. Batch mixing: Related control patterns

Understanding these fundamentals prepares you to implement effective Sequential Function Charts (SFC) solutions for Assembly Lines using Inovance InoProShop / AutoShop.

Implementing Assembly Lines with Sequential Function Charts (SFC)

Assembly line control systems coordinate the sequential addition of components to products as they move through workstations. PLCs manage station sequencing, operator interfaces, quality verification, and production tracking for efficient manufacturing.

This walkthrough demonstrates practical implementation using Inovance InoProShop / AutoShop and Sequential Function Charts (SFC) programming.

System Requirements:

A typical Assembly Lines implementation includes:

Input Devices (Sensors):
1. Part presence sensors for component verification: Critical for monitoring system state
2. Proximity sensors for fixture and tooling position: Critical for monitoring system state
3. Torque sensors for fastener verification: Critical for monitoring system state
4. Vision systems for assembly inspection: Critical for monitoring system state
5. Barcode/RFID readers for part tracking: Critical for monitoring system state

Output Devices (Actuators):
1. Pneumatic clamps and fixtures: Primary control output
2. Electric torque tools with controllers: Supporting control function
3. Pick-and-place mechanisms: Supporting control function
4. Servo presses for precision insertion: Supporting control function
5. Indexing conveyors and pallets: Supporting control function

Control Equipment:

  • Assembly workstations with fixtures

  • Pallet transfer systems

  • Automated guided vehicles (AGVs)

  • Collaborative robots (cobots)


Control Strategies for Assembly Lines:

1. Primary Control: Automated production assembly using PLCs for part handling, quality control, and production tracking.
2. Safety Interlocks: Preventing Cycle time optimization
3. Error Recovery: Handling Quality inspection

Implementation Steps:

Step 1: Document assembly sequence with cycle time targets per station

In InoProShop / AutoShop, document assembly sequence with cycle time targets per station.

Step 2: Define product variants and option configurations

In InoProShop / AutoShop, define product variants and option configurations.

Step 3: Create I/O list for all sensors, actuators, and operator interfaces

In InoProShop / AutoShop, create i/o list for all sensors, actuators, and operator interfaces.

Step 4: Implement station control logic with proper sequencing

In InoProShop / AutoShop, implement station control logic with proper sequencing.

Step 5: Add poka-yoke (error-proofing) verification for critical operations

In InoProShop / AutoShop, add poka-yoke (error-proofing) verification for critical operations.

Step 6: Program operator interface for cycle start, completion, and fault handling

In InoProShop / AutoShop, program operator interface for cycle start, completion, and fault handling.


Inovance Function Design:

InoProShop strongly favours function-block reuse via the Library Manager β€” Inovance ships standard libraries for motion, drives, HMI, OPC UA, and industry-specific applications (lithium-battery, EV, elevator). AutoShop reuse is open-coded via P-label subroutines. OEM machine-builders increasingly default to InoProShop / AM600 to access the FB libraries.

Common Challenges and Solutions:

1. Balancing work content across stations for consistent cycle time

  • Solution: Sequential Function Charts (SFC) addresses this through Perfect for sequential processes.


2. Handling product variants with different operations

  • Solution: Sequential Function Charts (SFC) addresses this through Clear visualization of process flow.


3. Managing parts supply and preventing stock-outs

  • Solution: Sequential Function Charts (SFC) addresses this through Easy to understand process steps.


4. Recovering from faults while maintaining quality

  • Solution: Sequential Function Charts (SFC) addresses this through Good for batch operations.


Safety Considerations:

  • Two-hand start buttons for manual stations

  • Light curtain muting for parts entry without stopping

  • Safe motion for collaborative robot operations

  • Lockout/tagout provisions for maintenance

  • Emergency stop zoning for partial line operation


Performance Metrics:

  • Scan Time: Optimize for 5 inputs and 5 outputs

  • Memory Usage: Efficient data structures for AM600 capabilities

  • Response Time: Meeting Manufacturing requirements for Assembly Lines

Inovance Diagnostic Tools:

InoProShop online mode with full POU monitoring and breakpoint debug,EtherCAT diagnostics page with topology and slave status,Trace tool for analogue / motion signal capture,OPC UA server diagnostics page,Modbus communication trace utility,AutoShop online mode for legacy AC800 / Easy series,Inovance HMI integrated diagnostics for HMI-PLC binding faults,Servo-drive panel diagnostics with InoProShop drive-monitor view,EtherCAT slave-firmware update tool,Project compare tool for change tracking

Inovance's InoProShop / AutoShop provides tools for performance monitoring and optimization, essential for achieving the 4-8 weeks development timeline while maintaining code quality.

Inovance Sequential Function Charts (SFC) Example for Assembly Lines

Complete working example demonstrating Sequential Function Charts (SFC) implementation for Assembly Lines using Inovance InoProShop / AutoShop. Follows Inovance naming conventions. Tested on AM600 hardware.

// Inovance InoProShop / AutoShop - Assembly Lines Control
// Sequential Function Charts (SFC) Implementation for Manufacturing
// On InoProShop projects, conventions follow CODESYS / IEC nor

// ============================================
// Variable Declarations
// ============================================
VAR
    bEnable : BOOL := FALSE;
    bEmergencyStop : BOOL := FALSE;
    rVisionsystems : REAL;
    rServomotors : REAL;
END_VAR

// ============================================
// Input Conditioning - Part presence sensors for component verification
// ============================================
// Standard input processing
IF rVisionsystems > 0.0 THEN
    bEnable := TRUE;
END_IF;

// ============================================
// Safety Interlock - Two-hand start buttons for manual stations
// ============================================
IF bEmergencyStop THEN
    rServomotors := 0.0;
    bEnable := FALSE;
END_IF;

// ============================================
// Main Assembly Lines Control Logic
// ============================================
IF bEnable AND NOT bEmergencyStop THEN
    // Assembly line control systems coordinate the sequential addi
    rServomotors := rVisionsystems * 1.0;

    // Process monitoring
    // Add specific control logic here
ELSE
    rServomotors := 0.0;
END_IF;

Code Explanation:

  • 1.Sequential Function Charts (SFC) structure optimized for Assembly Lines in Manufacturing applications
  • 2.Input conditioning handles Part presence sensors for component verification signals
  • 3.Safety interlock ensures Two-hand start buttons for manual stations always takes priority
  • 4.Main control implements Assembly line control systems coordinate
  • 5.Code runs every scan cycle on AM600 (typically 5-20ms)

Best Practices

  • βœ“Follow Inovance naming conventions: On InoProShop projects, conventions follow CODESYS / IEC norms β€” PascalCase for
  • βœ“Inovance function design: InoProShop strongly favours function-block reuse via the Library Manager β€” Inova
  • βœ“Data organization: InoProShop uses GVLs and persistent variables for shared data. AutoShop uses D /
  • βœ“Sequential Function Charts (SFC): Start with a clear process flow diagram before implementing SFC
  • βœ“Sequential Function Charts (SFC): Use descriptive step names indicating what happens (e.g., Filling, Heating)
  • βœ“Sequential Function Charts (SFC): Keep transition conditions simple - complex logic goes in action code
  • βœ“Assembly Lines: Implement operation-level process data logging
  • βœ“Assembly Lines: Use standard station control template for consistency
  • βœ“Assembly Lines: Add pre-emptive parts request to avoid stock-out
  • βœ“Debug with InoProShop / AutoShop: Use InoProShop's online mode to set breakpoints in POUs and step throu
  • βœ“Safety: Two-hand start buttons for manual stations
  • βœ“Use InoProShop / AutoShop simulation tools to test Assembly Lines logic before deployment

Common Pitfalls to Avoid

  • ⚠Sequential Function Charts (SFC): Forgetting to include stop/abort transitions for emergency handling
  • ⚠Sequential Function Charts (SFC): Creating deadlocks where no transition can fire
  • ⚠Sequential Function Charts (SFC): Not handling the case where transition conditions never become TRUE
  • ⚠Inovance common error: EtherCAT slave order mismatch after physical re-cabling β€” slave addressing break
  • ⚠Assembly Lines: Balancing work content across stations for consistent cycle time
  • ⚠Assembly Lines: Handling product variants with different operations
  • ⚠Neglecting to validate Part presence sensors for component verification leads to control errors
  • ⚠Insufficient comments make Sequential Function Charts (SFC) programs unmaintainable over time

Related Certifications

πŸ†Inovance Certified Engineer
πŸ†InoProShop / AutoShop training certificates
πŸ†EV / Lithium Battery automation specialist tracks

Mastering Sequential Function Charts (SFC) for Assembly Lines applications using Inovance InoProShop / AutoShop requires understanding both the platform's capabilities and the specific demands of Manufacturing. This guide has provided comprehensive coverage of implementation strategies, working code examples, best practices, and common pitfalls to help you succeed with intermediate to advanced Assembly Lines projects.

Inovance's ~2% global, top-3 in China market share and high in china across textiles, packaging, lithium battery, ev manufacturing, elevators, robotics; growing in se asia and mea demonstrate the platform's capability for demanding applications. The platform excels in Manufacturing applications where Assembly Lines reliability is critical.

By following the practices outlined in this guideβ€”from proper program structure and Sequential Function Charts (SFC) best practices to Inovance-specific optimizationsβ€”you can deliver reliable Assembly Lines systems that meet Manufacturing requirements.

Next Steps for Professional Development:

1. Certification: Pursue Inovance Certified Engineer to validate your Inovance expertise
2. Advanced Training: Consider InoProShop / AutoShop training certificates for specialized Manufacturing applications
3. Hands-on Practice: Build Assembly Lines projects using AM600 hardware
4. Stay Current: Follow InoProShop / AutoShop updates and new Sequential Function Charts (SFC) features

Sequential Function Charts (SFC) Foundation:

Sequential Function Chart (SFC) is a graphical language for programming sequential processes. It models systems as a series of steps connected by tran...

The 4-8 weeks typical timeline for Assembly Lines projects will decrease as you gain experience with these patterns and techniques. Remember: Implement operation-level process data logging

For further learning, explore related topics including Assembly sequences, Electronics manufacturing, and Inovance platform-specific features for Assembly Lines optimization.