Integrating Double-Seat Valves in SIMATIC PCS 7 - BRAUMAT VlvDS vs Industry Library VlvDsL

When integrating double-seat mixproof valves into a standard SIMATIC PCS 7 project, importing legacy BRAUMAT blocks (VlvDS) from demo projects fails to generate block icons and faceplates because BRAUMAT uses non-APL data structures and proprietary template files. To achieve full visualization, engineers must copy BRAUMAT's custom typicals (.pdl), faceplates (@pg_VlvDS*.pdl), and vector symbols (.emf) into the OS project's GraCS directory. Alternatively, deploying the standard SIMATIC PCS 7 Industry Library block VlvDsL (FB1103) provides native APL structure compatibility, seat-lift sequencing, and standard faceplates.

Double-Seat Mixproof Valve Automation Requirements

In sanitary processing, brewing, dairy, and beverage plants, double-seat mixproof valves isolate incompatible fluids (e.g., raw milk and caustic CIP cleaning solution) within a single valve manifold:
* The Physical Assembly:
Contains an upper valve seat and a lower valve seat with an atmospheric leakage drain cavity between them.
* Control Demands:
1. Main stroke actuation: Opening and closing the main process passage.
2. Upper seat lift (SeatLiftTop): Briefly opening the upper seat during cleaning to flush the upper seal.
3. Lower seat push (SeatLiftBottom): Opening the lower seat to flush the bottom chamber.
4. Pulsed cleaning timers: Precise synchronization to prevent fluid cross-contamination.

Why BRAUMAT VlvDS Fails to Auto-Generate Faceplates in Standard PCS 7

When an engineer copies VlvDS from a BRAUMAT demo project into a standard PCS 7 project:
* The Missing Template:
During OS compilation, the system searches @PCS7Typicals_APLV8.pdl for a block icon with type = @VlvDS/1. Because BRAUMAT is a separate specialized product line, standard APL typicals contain no definition for VlvDS.
* Missing Graphics and Bitmaps:
Even if the block icon is copied manually into a graphic picture, the internal Extended Status Display references specific vector bitmaps (e.g., bl_bi_vlvds_open.emf) and faceplate files (@pg_VlvDS.pdl). If these files are missing from the OS project's GraCS folder, the icon renders as an empty white box.

Comparison Table: BRAUMAT VlvDS vs Industry Library VlvDsL

The table below compares the two implementation pathways:

Engineering ParameterLegacy BRAUMAT VlvDSPCS 7 Industry Library VlvDsL (FB1103)Underlying StandardBRAUMAT ClassicNative Advanced Process Library (APL)Data TypesScalar (BOOL, BYTE, INT)APL Structures (Value, ST Quality Byte)Faceplate Look & FeelClassic BRAUMAT dialogs100% Uniform APL Style (Toolbar, Views)Seat Lift AutomationRequires custom PLC sequencingBuilt-in pulsing seat-lift timersOS Compile IntegrationRequires manual typicals copyingFully automated block icon generationLicensing RequirementBundled in BRAUMATIndustry Library License (6ES7658-1EX08-1YB5)

APL Structure Wrapping vs Legacy Scalar Variables

Modern PCS 7 APL blocks use standardized structured data types:

VAR_INPUT
    OpenAut : STRUCT
        Value : BOOL;
        ST    : BYTE; // Signal Status Quality Code (16#80 = Good)
    END_STRUCT;
END_VAR

Legacy BRAUMAT blocks pass raw booleans without signal status quality bytes. Attempting to connect an APL interlock block (Intlk02) directly to a legacy VlvDS requires inserting converter blocks (StrgToBy, BoolToStruct), drastically increasing CFC complexity.

Step-by-Step Procedure to Implement Double-Seat Valves in PCS 7

Method 1: Deploying Industry Library VlvDsL (Recommended):
* Open the Master Data Library. Under Libraries -> PCS 7 Industry Library -> IL_APL, locate VlvDsL (FB1103).
* Drag VlvDsL into your CFC charts.
* Interconnect main actuator commands (OpenAut), seat lift triggers (OpenTopAut, OpenBtmAut), and feedback limit switches.
* Execute an OS compilation. VlvDsL block icons generate automatically into assigned hierarchy pictures.
Method 2: Integrating BRAUMAT VlvDS (Manual Workaround):
* From the BRAUMAT demo project, copy the template block icon from @PCS7Typicals_BRAUMAT.pdl into your project's @PCS7TypicalsCustom.pdl.
* Copy all @pg_VlvDS*.pdl, @fp_VlvDS*.pdl, and associated .emf files into C:\<Project_Path>\wincproj\<OS_Name>\GraCS.
* Copy all C-scripts beginning with BL_ (e.g., BL_VlvDSOperationAreaOnOK.fct) into the project script directory.
* Perform an OS compile and run Create/Update Block Icons.

Verification

To verify double-seat valve functionality:
1. Open the WinCC OS Runtime screen containing the double-seat valve.
2. Confirm that the block icon displays the main valve body with upper and lower seat-lift indicators.
3. Click the icon to open the faceplate. Confirm that manual controls, interlock displays, and limit switch statuses animate accurately.
4. Test a seat-lift pulse: trigger OpenTopAut and verify that the upper seat opens for the configured duration without affecting main flow.

Limitations and Operational Precautions

Fluid Hammer Hazard: Rapid opening and closing of mixproof valve seats during high-pressure CIP pumping can induce severe water hammer. Always configure mechanical pulsation dampeners or ramping stroke speeds.
Drain Cavity Clog Detection: If mixproof valve drain lines become obstructed by product deposits, seat flushing liquid can bypass into process lines. Equip drain ports with optical sensors or conductivity probes.
Licensing Disclaimer: Utilizing the PCS 7 Industry Library (6ES7658-1EX08-1YB5) requires engineering and runtime licenses validated against the applicable Siemens catalog and authorized distributor quotation.