Loading WinCC Comfort Panel Recipes on Startup via TIA Portal

Overview

Comfort Panels (TP, KTP, KP, and MTP series) running WinCC Comfort or WinCC Advanced within TIA Portal can automatically load recipe data records at panel boot so that connected PLC tags reflect the correct process parameters before the operator screen appears. Because Comfort Panels do not expose a native "On Panel Start" system event the way some PLCs expose "On First Scan," the load action must be attached to a single-fire event such as the Activate event of a dedicated Start Screen, or driven by a one-shot trigger tag that a global VBScript observes exactly once.

This guide consolidates the two field-proven approaches (Start Screen activate event + System Function, and Trigger Tag value-change event + Script) and shows the equivalent VBScript calls for engineers who prefer code over the function table. It also documents the recipe data flow, the storage locations that WinCC supports, the synchronization modes between PLC and panel, and a verification checklist that catches the most common boot-time recipe faults before the panel is shipped to production.

Prerequisites

• TIA Portal V15.1 or later (V16, V17, V18, V19, V20 all behave identically for this workflow). Unified Comfort Panels require TIA V17 + HSP or later.
• Configured HMI connection between the Comfort Panel and the S7-1200, S7-1500, ET 200SP, or S7-300/400 PLC over PROFINET or PROFIBUS.
• Recipe definition created under HMI > Recipes > [Recipe name] with at least one data record element bound to a PLC tag.
• At least one stored data record in the panel's internal flash, USB stick, SD card, or network path.
• Panel runtime authorization (license) for recipes - included by default on Comfort and Unified Comfort Panels, but verify in Runtime Settings > Licensing.

Recipe Architecture in WinCC Comfort/Advanced

WinCC Comfort distinguishes between three logical layers that every startup load must reconcile:

1. Recipe definition - the symbolic container with element names, data types, and tag pointers. Compiled into the panel runtime.
2. Data records - the actual value sets. Stored on the panel file system (\Storage Card SD\Recipes, \USB\Recipes, or the internal flash \Recipes).
3. PLC tags - the runtime variables in the controller. A load operation copies the data record values into these tags.

When the panel boots, the runtime loads the project configuration but does not automatically push any data record to the PLC. The default behavior is to leave PLC tags at their last PLC-side value (or zero on a cold start of both PLC and panel). To force a load at startup you must trigger the LoadDataRecord (older TIA: LoadRecipe) system function - or call its VBScript equivalent HmiRuntime.ActiveRecipe / HmiRuntime.Recipes("Recipe_1").LoadDataRecord(1, 0) - exactly once per boot.

Method 1 - Start Screen with the Activate Event

This is the cleanest no-script solution and uses only configuration tables. The idea is to create a dedicated Start Screen whose Activate event runs exactly once when the runtime boots, executes the load function, and then activates the operator's normal Start Screen.

1. In the project tree, right-click Screens and select Add new screen. Rename it Screen_Startup. Set it as the Start screen under Runtime Settings > General > Start screen.
2. Open Screen_Startup and switch to the Events tab. On the Activate event, configure two system functions in this order:
   1. LoadDataRecord (recipe: your recipe name; data record number: 1; synchronization mode: 0 = load only if record exists)
   2. ActivateScreen (screen name: your original operator Start Screen, e.g. Screen_Process)
3. If the TIA Portal version exposes only ActivateCleanScreen in the function browser for a Comfort Panel, the panel is in a mode where the previous screen is not held in memory. Use ActivateCleanScreen instead - it performs the same navigation but releases the startup screen, freeing its memory footprint.
4. Compile the HMI project and download to the panel. Power-cycle the panel and observe the boot sequence: Screen_Startup should appear for < 200 ms, the load executes, and Screen_Process becomes active.

Method 2 - Trigger Tag with Value-Change Event

When the Start Screen approach is impractical - for example, the project uses a hard-coded start screen referenced by other automation logic - drive the load from a single-shot trigger tag.

1. Create an internal HMI tag, e.g. BootTrigger of type Int with a start value of 1.
2. Open any always-active scheduler or use the Once a day / Change scheduler to write a unique value to BootTrigger at runtime start. A clean approach is to use a global VBScript that runs at runtime start; see Method 3.
3. On the tag's Value change event, call LoadDataRecord (recipe name, record number, sync mode).
4. After the load, the script can reset BootTrigger to a sentinel value so the value-change event will not refire on every cyclic write.

This method is the recommended fallback when the Activate event of the Start Screen cannot be used because the screen is used for other purposes later in the runtime.

Method 3 - VBScript with Screen Number Tag

For engineers who prefer a single code block that handles navigation, loading, and logging, VBScript on a global trigger tag is the most flexible approach.

1. Create an HMI tag BootStep (Int) with initial value 0.
2. In Project tree > Scripts > Global area create a new VBScript function, e.g. Boot_LoadRecipe.
3. On the Value change event of BootStep, add a system function to run this script.

Example script body (TIA Portal V17 / V18 syntax):

' Boot_LoadRecipe - runs once per panel boot
Sub Boot_LoadRecipe()
    Dim recipeName, recordNum, syncMode
    recipeName = "Recipe_Process"
    recordNum  = 1
    syncMode   = 0        ' 0 = load, 1 = synchronize (PLC wins), 2 = overwrite (record wins)

    On Error Resume Next
    HmiRuntime.ActiveRecipe = recipeName
    HmiRuntime.Recipes(recipeName).LoadDataRecord recordNum, syncMode
    If Err.Number <> 0 Then
        HmiRuntime.Trace "Boot load failed: " & Err.Description & vbCrLf
    Else
        HmiRuntime.Trace "Boot load OK: " & recipeName & " record " & recordNum & vbCrLf
    End If
    On Error Goto 0

    HmiRuntime.Screens("Screen_Process").Activate
    HmiRuntime.Tags("BootStep").Write 9999   ' sentinel - prevents re-trigger
End Sub

To call the script at panel start without a manual action, set BootStep to a non-sentinel value (for example 1) from a project-wide Initialize event: open the project tree root > Events > Runtime started and configure Set tag to write 1 into BootStep. The runtime-start event is available in TIA Portal V17 and later on Comfort Panels and is the closest equivalent to a true "On Panel Start" event.

System Function and VBScript Reference

Recipe Storage Paths on a Comfort Panel

The path is configured under Recipe > Properties > Storage paths. When the panel boots without the SD card or USB stick, LoadDataRecord will return an error code - see the verification section for which tag to read to detect this.

PLC-Side Handshake (Recommended for Robust Loads)

To confirm the panel has actually pushed the values to the PLC, build a small handshake:

1. Define an HMI tag HMI_RecipeLoaded (Bool) bound to a PLC tag in DB100 (e.g. DB100.DBX0.0).
2. Define an HMI tag PLC_RecipeAck (Bool) bound to DB100.DBX0.1.
3. On the panel's Start Screen Activate event, configure: LoadDataRecord, Set tag (HMI_RecipeLoaded = 1), ActivateScreen.
4. In the PLC OB1 or OB100, monitor HMI_RecipeLoaded. When it goes high, latch a "Recipe values valid" bit for downstream logic and write PLC_RecipeAck = 1.
5. On the panel's PLC_RecipeAck value-change event, reset HMI_RecipeLoaded to 0 so the load will refire correctly on the next boot.

This handshake prevents the classic failure mode where the panel reports success but the PLC tag was overwritten by an OB100 initialization a few milliseconds later.

Verification Checklist

1. Boot trace - Enable Runtime Settings > Services > Trace with output to a file. The "Boot load OK: ..." trace line should appear once per power-cycle.
2. Tag inspector - Open Online > Tag monitor on the panel and the PLC. After boot, the PLC tags must equal the loaded data record's values, not zero and not the last PLC-side value.
3. Re-trigger test - Power-cycle the panel three times. Confirm the load fires only once per cycle by checking the trace log count.
4. Storage presence - With the SD card removed, verify the load still succeeds from internal flash. With the SD card present and the storage path set to it, verify the SD card version loads.
5. License check - In Runtime Settings > Licensing confirm the Recipes option is licensed; otherwise LoadDataRecord silently returns error 0x8004xxxx.
6. Single-fire check - Navigate operator screens, return to Start Screen, and confirm the Activate event does not refire. If it does, the Start Screen is reachable by user navigation; replace it with a screen whose name is hidden from the navigation tree.

Troubleshooting Matrix

Migration Notes Between TIA Portal Versions

Recipes were reworked across TIA Portal major releases. On projects migrated from V13/V14, the legacy function names LoadRecipe / SaveRecipe appear in the function browser but are internally aliased to LoadDataRecord / SaveDataRecord. The VBScript object model also changed: in V13, the recipe was reached via HMIRuntime.ActiveScreen.ScreenItems("...") in some configurations, while V17 onward uses HmiRuntime.Recipes("...").LoadDataRecord n, mode. When porting older scripts, verify both the object path and the parameter order - the legacy two-parameter signature (n) still works, but the three-parameter signature (n, mode) is required when you need explicit synchronization control.

Related WinCC Comfort Functions Worth Knowing

• SetRecipeValue / GetRecipeValue - read or write a single element of the active record without a full load, useful for boot-time patching.
• ReadUserArchive - for larger structured datasets beyond recipes (separate licensing).
• SetConnectionMode - force the HMI connection online before the load runs, eliminating the "connection not yet established" race.
• SimulateTag - in the simulator, simulate recipe tags offline without a real PLC for HMI FAT testing.

For deeper coverage, refer to the TIA Portal Help Portal entries on WinCC Comfort - Working with Recipes and the S7-1200 / S7-1500 communication manuals. The Siemens Industry Online Support (SIOS) entry "Comfort Panel - Loading recipes automatically" is the canonical KB for this workflow.

FAQ