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Intermediate15 min readIndustrial Manufacturing

Inovance Sequential Function Charts (SFC) for Motor Control

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

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Platform
InoProShop / AutoShop
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Complexity
Beginner to Intermediate
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Project Duration
1-3 weeks

Learning to implement Sequential Function Charts (SFC) for Motor Control using Inovance's InoProShop / AutoShop is a useful skill for PLC programmers working in Industrial Manufacturing. This guide walks through the fundamentals with clear explanations and an illustrative example that you can adapt to a simulator or test bench.

The example uses Inovance terminology and references controller families such as AM600 and AM610. Confirm the exact instructions, data types, firmware requirements, and licensing in the current vendor documentation before choosing hardware or deploying a project.

The Sequential Function Charts (SFC) approach is particularly well-suited for Motor Control because batch processes, step-by-step operations, state machines, and complex sequential control. This combination allows you to leverage perfect for sequential processes while managing the typical challenges of Motor Control, including soft start implementation and overload protection.

Throughout this guide, you'll find step-by-step implementation guidance, an illustrative code example, and a verification checklist specific to Industrial Manufacturing. Whether you're programming your first Motor Control exercise or transitioning from another PLC platform, use the material as a starting point and validate it in your exact InoProShop / AutoShop version and controller environment.

Inovance InoProShop / AutoShop for Motor Control

InoProShop / AutoShop is a programming environment associated with Inovance controller families such as AM600, AM610, H5U. This guide uses Sequential Function Charts (SFC) terminology from the supplied guide dataset, but controller capabilities and language support can change by model, firmware, software edition, and license.

Verify Before You Start:

  • The selected controller supports the required Sequential Function Charts (SFC) constructs

  • The project version matches the installed InoProShop / AutoShop release

  • Required communications, motion, safety, and simulation options are licensed

  • Firmware and device-description files are compatible with the project

  • The vendor manuals used for the design match the exact hardware revision


Application Planning:

For a Motor Control exercise, map the required inputs and outputs before writing logic. The example considers 5 sensor types, including Current sensors, Vibration sensors, Temperature sensors, and 5 actuator types.

Control Equipment for Motor Control:

  • Motor control centers (MCCs)

  • AC induction motors (NEMA/IEC frame)

  • Synchronous motors for high efficiency

  • DC motors for precise speed control


Controller-family references used in this guide include:

  • AM600: Confirm CPU, I/O, memory, communications, and Sequential Function Charts (SFC) support in the current selection guide

  • AM610: Confirm CPU, I/O, memory, communications, and Sequential Function Charts (SFC) support in the current selection guide

  • H5U: Confirm CPU, I/O, memory, communications, and Sequential Function Charts (SFC) support in the current selection guide

  • AC800: Confirm CPU, I/O, memory, communications, and Sequential Function Charts (SFC) support in the current selection guide


Hardware Selection Checklist:

  • Count local and remote I/O, including planned expansion

  • Measure the required task and communications update rates

  • Identify memory, data-retention, diagnostics, and cybersecurity requirements

  • Treat safety functions as a separate, standards-led design activity

  • Confirm lifecycle status, regional availability, licensing, and support


Source and Validation Note:

This page does not represent a vendor certification or a hardware acceptance test. Use current Inovance manuals, release notes, and safety documentation as the authority for product-specific behavior. Validate adapted logic in a simulator or isolated test setup before connecting it to equipment.

Investment Considerations:

For Motor Control projects, compare hardware, software licensing, training, engineering, test equipment, commissioning, spares, and ongoing support. Obtain current pricing and lifecycle information directly from the vendor or an authorized regional supplier.

Understanding Sequential Function Charts (SFC) for Motor Control

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 Motor Control:

  • Perfect for sequential processes: Critical for Motor Control when handling beginner to intermediate control logic

  • Clear visualization of process flow: Critical for Motor Control when handling beginner to intermediate control logic

  • Easy to understand process steps: Critical for Motor Control when handling beginner to intermediate control logic

  • Good for batch operations: Critical for Motor Control when handling beginner to intermediate control logic

  • Simplifies complex sequences: Critical for Motor Control when handling beginner to intermediate control logic


Why Sequential Function Charts (SFC) Fits Motor Control:

Motor Control systems in Industrial Manufacturing typically involve:

  • Sensors: Current transformers for motor current monitoring, RTD or thermocouple for motor winding temperature, Vibration sensors for bearing monitoring

  • Actuators: Contactors for direct-on-line starting, Soft starters for reduced voltage starting, Variable frequency drives for speed control

  • Complexity: Beginner to Intermediate with challenges including Managing starting current within supply limits


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 Motor Control
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 Motor Control using Inovance InoProShop / AutoShop.

Implementing Motor Control with Sequential Function Charts (SFC)

Motor control systems use PLCs to start, stop, and regulate electric motors in industrial applications. These systems provide protection, speed control, and coordination for motors ranging from fractional horsepower to thousands of horsepower.

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

System Requirements:

A typical Motor Control implementation includes:

Input Devices (Sensors):
1. Current transformers for motor current monitoring: Critical for monitoring system state
2. RTD or thermocouple for motor winding temperature: Critical for monitoring system state
3. Vibration sensors for bearing monitoring: Critical for monitoring system state
4. Speed encoders or tachometers: Critical for monitoring system state
5. Torque sensors for load monitoring: Critical for monitoring system state

Output Devices (Actuators):
1. Contactors for direct-on-line starting: Primary control output
2. Soft starters for reduced voltage starting: Supporting control function
3. Variable frequency drives for speed control: Supporting control function
4. Brakes (mechanical or dynamic): Supporting control function
5. Starters (star-delta, autotransformer): Supporting control function

Control Equipment:

  • Motor control centers (MCCs)

  • AC induction motors (NEMA/IEC frame)

  • Synchronous motors for high efficiency

  • DC motors for precise speed control


Control Strategies for Motor Control:

1. Primary Control: Industrial motor control using PLCs for start/stop, speed control, and protection of electric motors.
2. Safety Interlocks: Preventing Soft start implementation
3. Error Recovery: Handling Overload protection

Implementation Steps:

Step 1: Calculate motor starting current and verify supply capacity

In InoProShop / AutoShop, calculate motor starting current and verify supply capacity.

Step 2: Select starting method based on motor size and load requirements

In InoProShop / AutoShop, select starting method based on motor size and load requirements.

Step 3: Configure motor protection with correct thermal curve

In InoProShop / AutoShop, configure motor protection with correct thermal curve.

Step 4: Implement control logic for start/stop with proper interlocks

In InoProShop / AutoShop, implement control logic for start/stop with proper interlocks.

Step 5: Add speed control loop if VFD is used

In InoProShop / AutoShop, add speed control loop if vfd is used.

Step 6: Configure acceleration and deceleration ramps

In InoProShop / AutoShop, configure acceleration and deceleration ramps.


Inovance Function Design:

InoProShop strongly favours function-block reuse via the Library Manager — 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. Managing starting current within supply limits

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


2. Coordinating acceleration with driven load requirements

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


3. Protecting motors from frequent starting (thermal cycling)

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


4. Handling regenerative energy during deceleration

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


Safety Considerations:

  • Proper machine guarding for rotating equipment

  • Emergency stop functionality with safe torque off

  • Lockout/tagout provisions for maintenance

  • Arc flash protection and PPE requirements

  • Proper grounding and bonding


Performance Metrics:

  • Task and I/O timing: Record minimum, average, and maximum values under a defined test load

  • Accuracy: Define an acceptable tolerance and compare it with calibrated reference measurements

  • Throughput: Count completed cycles over a fixed interval and record rejected or incomplete cycles

  • Fault response: Measure detection, safe-state, alarm, and recovery behavior for each test case

  • Resource use: Record memory, communications load, and diagnostic-buffer behavior

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

Use the monitoring and diagnostic functions available in your InoProShop / AutoShop version, and record the software, firmware, hardware, workload, and test procedure with every result.

Inovance Sequential Function Charts (SFC) Example for Motor Control

Illustrative Sequential Function Charts (SFC) example for Motor Control using Inovance terminology. Adapt the syntax to your InoProShop / AutoShop release, compile it, and verify it in an isolated test environment before use on equipment.

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

// ============================================
// Variable Declarations
// ============================================
VAR
    bEnable : BOOL := FALSE;
    bEmergencyStop : BOOL := FALSE;
    rCurrentsensors : REAL;
    rMotorstarters : REAL;
END_VAR

// ============================================
// Input Conditioning - Current transformers for motor current monitoring
// ============================================
// Standard input processing
IF rCurrentsensors > 0.0 THEN
    bEnable := TRUE;
END_IF;

// ============================================
// Safety Interlock - Proper machine guarding for rotating equipment
// ============================================
IF bEmergencyStop THEN
    rMotorstarters := 0.0;
    bEnable := FALSE;
END_IF;

// ============================================
// Main Motor Control Control Logic
// ============================================
IF bEnable AND NOT bEmergencyStop THEN
    // Motor control systems use PLCs to start, stop, and regulate 
    rMotorstarters := rCurrentsensors * 1.0; (* Illustrative scaling only *)

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

Code Explanation:

  • 1.Sequential Function Charts (SFC) structure organized for a Motor Control training example
  • 2.Input conditioning handles Current transformers for motor current monitoring signals
  • 3.Safety interlock ensures Proper machine guarding for rotating equipment always takes priority
  • 4.Main control implements Motor control systems use PLCs to start,
  • 5.Adapt the scan-cycle assumptions to the selected AM600 task configuration and verify them by measurement

Best Practices

  • Follow Inovance naming conventions: On InoProShop projects, conventions follow CODESYS / IEC norms — PascalCase for
  • Inovance function design: InoProShop strongly favours function-block reuse via the Library Manager — Inova
  • Data organization: InoProShop uses GVLs and persistent variables for shared data. AutoShop uses D /
  • Sequential Function Charts (SFC): Start with a clear process flow diagram before implementing SFC
  • Sequential Function Charts (SFC): Use descriptive step names indicating what happens (e.g., Filling, Heating)
  • Sequential Function Charts (SFC): Keep transition conditions simple - complex logic goes in action code
  • Motor Control: Verify motor running with current or speed feedback, not just contactor status
  • Motor Control: Implement minimum off time between starts for motor cooling
  • Motor Control: Add phase loss and phase reversal protection
  • Debug with InoProShop / AutoShop: Use InoProShop's online mode to set breakpoints in POUs and step throu
  • Safety: Proper machine guarding for rotating equipment
  • Use a compatible simulator or isolated test rig to test Motor Control 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 — slave addressing break
  • Motor Control: Managing starting current within supply limits
  • Motor Control: Coordinating acceleration with driven load requirements
  • Neglecting to validate Current transformers for motor current monitoring leads to control errors
  • Insufficient comments make Sequential Function Charts (SFC) programs unmaintainable over time

Related Certifications

🏆Inovance Certified Engineer
🏆InoProShop / AutoShop training certificates
🏆EV / Lithium Battery automation specialist tracks

Applying Sequential Function Charts (SFC) to Motor Control using Inovance InoProShop / AutoShop requires understanding the platform, the process, and the project's acceptance criteria. This guide has covered implementation structure, an illustrative code example, verification practices, and common pitfalls for a beginner to intermediate Motor Control exercise.

Use the practices outlined here to create a design that can be reviewed and tested. Define performance targets in the project requirements and confirm them with repeatable measurements.

Next Steps:

1. Check Sources: Read the current InoProShop / AutoShop help, controller manual, release notes, and relevant standards
2. Practice Safely: Adapt the example in a simulator or isolated training setup
3. Review: Have the I/O map, state behavior, faults, and recovery steps reviewed
4. Test: Record normal, boundary, fault, restart, and communications test results

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...

Project duration depends on scope, reviews, hardware availability, software and firmware versions, testing, commissioning, and site constraints. Remember: Verify motor running with current or speed feedback, not just contactor status

For further learning, explore related topics including Assembly sequences, Fan systems, and Inovance platform-specific features for Motor Control optimization.