Optimizing Sequential Function Charts (SFC) for Temperature Control applications in Inovance's InoProShop / AutoShop requires measuring the baseline and understanding the demands of Process Control. This guide focuses on techniques you can evaluate with task timing, scan-time traces, memory use, and controlled fault tests.
For intermediate applications like Temperature Control, check which diagnostics and profiling tools are available in your installed InoProShop / AutoShop version. Controller model, firmware, task configuration, communications, and I/O update behavior can all affect the result.
Performance considerations for Temperature Control systems extend beyond basic functionality. Critical factors include 4 sensor types, 5 actuators, communications load, and the need to handle pid tuning. Evaluate whether perfect for sequential processes helps the design, then measure the actual task and I/O timing on the selected configuration.
This guide covers memory management, execution order, Sequential Function Charts (SFC)-specific tuning, and a repeatable measurement plan for Temperature Control applications. Treat every optimization as a hypothesis: record the baseline, change one variable, retest the same workload, and keep the change only when the measured result and code maintainability both improve.
Inovance InoProShop / AutoShop for Temperature 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 Temperature Control exercise, map the required inputs and outputs before writing logic. The example considers 4 sensor types, including Thermocouples (K-type, J-type), RTD sensors (PT100, PT1000), Infrared temperature sensors, and 5 actuator types.
Control Equipment for Temperature Control:
- Electric resistance heaters (cartridge, band, strip)
- Steam injection systems
- Thermal fluid (hot oil) systems
- Refrigeration and chiller systems
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 Temperature 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 Temperature 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 Temperature Control:
- Perfect for sequential processes: Critical for Temperature Control when handling intermediate control logic
- Clear visualization of process flow: Critical for Temperature Control when handling intermediate control logic
- Easy to understand process steps: Critical for Temperature Control when handling intermediate control logic
- Good for batch operations: Critical for Temperature Control when handling intermediate control logic
- Simplifies complex sequences: Critical for Temperature Control when handling intermediate control logic
Why Sequential Function Charts (SFC) Fits Temperature Control:
Temperature Control systems in Process Control typically involve:
- Sensors: RTDs (PT100/PT1000) for high-accuracy measurements, Thermocouples (J, K, T types) for high-temperature applications, Infrared pyrometers for non-contact measurement
- Actuators: SCR (thyristor) power controllers for electric heaters, Solid-state relays for on/off heating control, Proportional control valves for steam or thermal fluid
- Complexity: Intermediate with challenges including Long thermal time constants making tuning difficult
Control Strategies for Temperature Control:
- pid: Standard PID control with proportional, integral, and derivative terms tuned for the thermal process dynamics
- cascade: Master temperature loop outputs to slave heater/cooler control loop for tighter control
- ratio: Maintain temperature ratio between zones for gradient applications
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 Temperature 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 Temperature Control using Inovance InoProShop / AutoShop.
Implementing Temperature Control with Sequential Function Charts (SFC)
Industrial temperature control systems use PLCs to regulate process temperatures in manufacturing, food processing, chemical processing, and other applications. These systems maintain precise temperature setpoints through heating and cooling control while ensuring product quality and energy efficiency.
This walkthrough demonstrates practical implementation using Inovance InoProShop / AutoShop and Sequential Function Charts (SFC) programming.
System Requirements:
A typical Temperature Control implementation includes:
Input Devices (Sensors):
1. RTDs (PT100/PT1000) for high-accuracy measurements: Critical for monitoring system state
2. Thermocouples (J, K, T types) for high-temperature applications: Critical for monitoring system state
3. Infrared pyrometers for non-contact measurement: Critical for monitoring system state
4. Thermistors for fast response applications: Critical for monitoring system state
5. Thermal imaging cameras for surface temperature monitoring: Critical for monitoring system state
Output Devices (Actuators):
1. SCR (thyristor) power controllers for electric heaters: Primary control output
2. Solid-state relays for on/off heating control: Supporting control function
3. Proportional control valves for steam or thermal fluid: Supporting control function
4. Solenoid valves for cooling water or refrigerant: Supporting control function
5. Variable frequency drives for cooling fan control: Supporting control function
Control Equipment:
- Electric resistance heaters (cartridge, band, strip)
- Steam injection systems
- Thermal fluid (hot oil) systems
- Refrigeration and chiller systems
Control Strategies for Temperature Control:
- pid: Standard PID control with proportional, integral, and derivative terms tuned for the thermal process dynamics
- cascade: Master temperature loop outputs to slave heater/cooler control loop for tighter control
- ratio: Maintain temperature ratio between zones for gradient applications
Implementation Steps:
Step 1: Characterize thermal system dynamics (time constants, dead time)
In InoProShop / AutoShop, characterize thermal system dynamics (time constants, dead time).
Step 2: Select appropriate sensor type and placement for representative measurement
In InoProShop / AutoShop, select appropriate sensor type and placement for representative measurement.
Step 3: Size heating and cooling capacity for worst-case load conditions
In InoProShop / AutoShop, size heating and cooling capacity for worst-case load conditions.
Step 4: Implement PID control with appropriate sample time (typically 10x faster than process time constant)
In InoProShop / AutoShop, implement pid control with appropriate sample time (typically 10x faster than process time constant).
Step 5: Add output limiting and anti-windup for safe operation
In InoProShop / AutoShop, add output limiting and anti-windup for safe operation.
Step 6: Program ramp/soak profiles if required
In InoProShop / AutoShop, program ramp/soak profiles if required.
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. Long thermal time constants making tuning difficult
- Solution: Sequential Function Charts (SFC) addresses this through Perfect for sequential processes.
2. Transport delay (dead time) causing instability
- Solution: Sequential Function Charts (SFC) addresses this through Clear visualization of process flow.
3. Non-linear response at different temperature ranges
- Solution: Sequential Function Charts (SFC) addresses this through Easy to understand process steps.
4. Sensor placement affecting measurement accuracy
- Solution: Sequential Function Charts (SFC) addresses this through Good for batch operations.
Safety Considerations:
- Independent high-limit safety thermostats (redundant to PLC)
- Watchdog timers for heater control validity
- Safe-state definition on controller failure (heaters off)
- Thermal fuse backup for runaway conditions
- Proper ventilation for combustible atmospheres
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 Temperature Control
Illustrative Sequential Function Charts (SFC) example for Temperature 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 - Temperature Control Control
// Sequential Function Charts (SFC) Implementation for Process Control
// On InoProShop projects, conventions follow CODESYS / IEC nor
// ============================================
// Variable Declarations
// ============================================
VAR
bEnable : BOOL := FALSE;
bEmergencyStop : BOOL := FALSE;
rThermocouplesKtypeJtype : REAL;
rHeatingelements : REAL;
END_VAR
// ============================================
// Input Conditioning - RTDs (PT100/PT1000) for high-accuracy measurements
// ============================================
// Standard input processing
IF rThermocouplesKtypeJtype > 0.0 THEN
bEnable := TRUE;
END_IF;
// ============================================
// Safety Interlock - Independent high-limit safety thermostats (redundant to PLC)
// ============================================
IF bEmergencyStop THEN
rHeatingelements := 0.0;
bEnable := FALSE;
END_IF;
// ============================================
// Main Temperature Control Control Logic
// ============================================
IF bEnable AND NOT bEmergencyStop THEN
// Industrial temperature control systems use PLCs to regulate
rHeatingelements := rThermocouplesKtypeJtype * 1.0; (* Illustrative scaling only *)
// Process monitoring
// Add specific control logic here
ELSE
rHeatingelements := 0.0;
END_IF;Code Explanation:
- 1.Sequential Function Charts (SFC) structure organized for a Temperature Control training example
- 2.Input conditioning handles RTDs (PT100/PT1000) for high-accuracy measurements signals
- 3.Safety interlock ensures Independent high-limit safety thermostats (redundant to PLC) always takes priority
- 4.Main control implements Industrial temperature control systems u
- 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
- ✓Temperature Control: Sample at 1/10 of the process time constant minimum
- ✓Temperature Control: Use derivative on PV, not error, for temperature control
- ✓Temperature Control: Start with conservative tuning and tighten gradually
- ✓Debug with InoProShop / AutoShop: Use InoProShop's online mode to set breakpoints in POUs and step throu
- ✓Safety: Independent high-limit safety thermostats (redundant to PLC)
- ✓Use a compatible simulator or isolated test rig to test Temperature 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
- ⚠Temperature Control: Long thermal time constants making tuning difficult
- ⚠Temperature Control: Transport delay (dead time) causing instability
- ⚠Neglecting to validate RTDs (PT100/PT1000) for high-accuracy measurements leads to control errors
- ⚠Insufficient comments make Sequential Function Charts (SFC) programs unmaintainable over time
Related Certifications
Applying Sequential Function Charts (SFC) to Temperature 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 intermediate Temperature 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: Sample at 1/10 of the process time constant minimum
For further learning, explore related topics including Assembly sequences, Plastic molding machines, and Inovance platform-specific features for Temperature Control optimization.