Inside AutomationView: Creating Reusable SFC Templates to Standardize PLC Engineering

flowchart LR
    A["Mechanical Spec"] --> B["AutomationView SFC"]
    B --> C["Standardized POU"]
    C --> D["Multi-Vendor PLC Deployment"]
    
    style A fill:#2563eb,stroke:#1d4ed8,color:#ffffff
    style B fill:#16a34a,stroke:#15803d,color:#ffffff
    style C fill:#d97706,stroke:#b45309,color:#ffffff
    style D fill:#dc2626,stroke:#b91c1c,color:#ffffff

Every automation engineer knows the headache of reverse-engineering “spaghetti logic” on a Monday morning. When ten different programmers touch a machine line over five years, the result is often a chaotic mix of undocumented ladder rungs, conflicting state machines, and bypassed safety interlocks. Standardizing control logic isn’t just about clean code; it’s about reducing downtime and ensuring that maintenance technicians can troubleshoot a fault at 3 AM without calling the original developer.

Sequential Function Chart (SFC) provides a native, visual framework for standardizing complex machine sequences. By leveraging AutomationView to build and deploy reusable SFC Templates, engineering teams can bridge the gap between mechanical design and functional software, creating a modular architecture that scales across multiple hardware platforms.

Key Takeaways

• Standardized SFC templates reduce repetitive coding and accelerate commissioning timelines.
• State-based design isolates high-level sequencing from low-level equipment control logic.
• AutomationView allows engineers to build, simulate, and version-control reusable POUs before hardware deployment.
• Consistent naming conventions and architectural patterns drastically improve long-term code maintainability.

The Flaws of Ad-Hoc Sequence Programming

In traditional PLC programming, sequences are frequently hardcoded directly into continuous task routines. Engineers might use integer state trackers or cascading latch relays to step through a process. While this works for simple mechanisms, it scales poorly. When modifying a sequence step requires digging through interlocking rungs, the risk of unintended side effects skyrockets.

Furthermore, without a standardized template, every new machine project starts from scratch. A Pick-and-Place routine written by an engineer in Chicago will look fundamentally different from one written by a colleague in Munich, even if the mechanical hardware is identical. This lack of standardization inflates training costs and complicates field support.

Architecting Reusable SFC Templates in AutomationView

IEC 61131-3 defines Sequential Function Chart as a top-level organizational tool. Rather than replacing Ladder Diagram (LD) or Structured Text (ST), SFC organizes them. A robust SFC template acts as the traffic controller, managing the execution of underlying control modules.

AutomationView enhances this by allowing engineers to design graphical state machines that are intrinsically tied to version control and simulation. Instead of building a bespoke sequence for every pneumatic cylinder or servo axis, you can design a master template for a generic “Station Sequence.”

flowchart TD
    subgraph execution_flow ["Standard Station Sequence"]
        S1["Init_State"] --> T1["Conditions_Met"]
        T1 --> S2["Home_Routine"]
        S2 --> T2["Homing_Complete"]
        T2 --> S3["Auto_Running"]
        S3 --> T3["Fault_Detected"]
        T3 --> S4["Error_Handling"]
        S4 --> T4["Reset_Triggered"]
        T4 --> S1
    end
    
    style S1 fill:#2563eb,stroke:#ffffff,color:#ffffff
    style S2 fill:#16a34a,stroke:#ffffff,color:#ffffff
    style S3 fill:#16a34a,stroke:#ffffff,color:#ffffff
    style S4 fill:#dc2626,stroke:#ffffff,color:#ffffff

Isolating Logic Layers

A critical best practice for SFC Templates is separating the sequence from the equipment logic. The SFC should only define when an action happens, not how it happens.

For example, if step three of a sequence requires a clamp to close, the SFC Action Block should simply set a boolean flag (e.g., Cmd_ClampClose). A separate, continuous equipment module reads this flag, evaluates physical interlocks, and fires the actual output coil. This decoupling means the SFC Template remains completely hardware-agnostic. If you swap a pneumatic clamp for an electric gripper, the sequence logic remains untouched.

Standardization Through AutomationView Workflows

When developing SFC Templates within AutomationView, teams can enforce consistency across the entire organization. This is achieved through structured project libraries and mandatory design reviews facilitated by Git integration.

Once a template (such as an Equipment Module or a generic Homing Sequence) is verified against the internal simulation engine, it is committed to the central AutomationView repository. New projects pull from this repository, guaranteeing that every machine ships with the same foundational architecture.

Comparing Sequence Implementations

Transitioning to an SFC-based template architecture requires an initial investment in design, but the long-term ROI is substantial. Here is how a template-driven approach compares to traditional programming.

Bridging the Gap to Multi-Vendor Deployment

One of the hardest challenges in industrial automation is maintaining a standard architecture across different PLC brands. A sequence written for Siemens TIA Portal usually needs complete rewriting for Rockwell Studio 5000.

By defining your sequences as SFC Templates within AutomationView, you abstract the logic from the vendor-specific IDE. AutomationView’s export capabilities allow the standardized IEC 61131-3 logic to be deployed seamlessly to various targets. The template dictates the behavior, and the compiler handles the syntax translation.

Conclusion

Relying on ad-hoc programming for machine sequences is an unsustainable practice for modern automation teams. Adopting a modular, template-driven approach using Sequential Function Chart (SFC) significantly enhances code maintainability, reduces commissioning time, and standardizes operations across multi-vendor deployments. AutomationView provides the ideal environment to design, simulate, and manage these SFC Templates, ensuring that your engineering effort is scalable and robust.

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