Opening Pop-Up Windows in WinCC WebNavigator V7.4: Supported Web Functions vs Desktop Split Screen Manager

In SIMATIC WinCC WebNavigator V7.4 (including SP1 and Upd1), attempting to open faceplate pop-up windows using Split Screen Manager (SSM) functions such as SSMRTOpenTopField2 or SSMOpenTopField fails because desktop multi-monitor and coordinate management APIs are strictly unsupported on WebNavigator Clients. The WinCC Basic Process Control (BPC) Web plugin does not port native Win32 window handles into the web browser ActiveX sandbox. To open pop-up windows reliably in WebNavigator, engineers must utilize Web-compatible methods: manipulating pre-configured WinCC Picture Windows via SetVisible and SetPictureName, or using standard APL web-enabled faceplate scripts.

Architecture of WinCC WebNavigator Client vs Desktop WinCC Runtime

SIMATIC WinCC WebNavigator provides thin-client process visualization over corporate intranets and the Internet. Process pictures (*.pdl) are published to a web server running Microsoft Internet Information Services (IIS). Operators access plant mimics through Internet Explorer using the WinCC WebNavigator Client ActiveX control.

While standard graphic shapes, direct connections, and basic scripts operate identically to desktop WinCC, the runtime environment is fundamentally different: WebNavigator executes inside a restricted browser sandbox without access to native Windows desktop APIs or multi-screen coordinate hooks.

Why Split Screen Manager (SSM) Functions Fail in WebNavigator

In desktop PCS 7 systems, Basic Process Control relies on the Split Screen Manager (SSM) to manage multi-monitor arrangements, overview banners, alarm lines, and floating faceplates:

Functions such as SSMRTOpenTopField2, SSMOpenTopField, and SSMOpenScreen query Windows display driver handles (HWND) to position windows precisely across 1 to 4 physical monitors.
On a WebNavigator Client, the entire WinCC runtime is hosted inside a single browser canvas. WinCC has no access to external desktop monitor coordinates. Calling SSMRTOpenTopField2 fails silently or throws an unsupported function exception in the Web client console.

The WinCC Basic Process Control (BPC) Web Plugin Scope and Boundaries

A frequent misconception is that installing the WinCC Basic Process Control Plugin for WebNavigator enables all desktop SSM functions:

The BPC Web Plugin provides the runtime infrastructure for picture tree hierarchy navigation, alarm line rendering, and group display hierarchies.
It does NOT implement multi-window desktop window managers.
The official WinCC Information System documentation (under WinCC/WebNavigator -> Appendix -> Functions -> Supported Functions) explicitly omits SSMRTOpenTopField2 from the supported API whitelist.

Web-Compatible Pop-up Implementations: Picture Windows and Dynamic Scripting

To display faceplates or pop-up dialogues on WebNavigator clients, use Picture Window components embedded within the master plant screen:

The Picture Window Container: Insert a Picture Window object into the screen (e.g., named Faceplate_Container). Set its initial visibility to FALSE.
Dynamic Loading on Click: In the click event of the object icon, execute standard Web-supported C-scripts or VBScript:
c SetPropChar(lpszPictureName, "Faceplate_Container", "TagPrefix", "Motor_101."); SetPropChar(lpszPictureName, "Faceplate_Container", "PictureName", "@PG_C_DRV_1D.PDL"); SetPropBOOL(lpszPictureName, "Faceplate_Container", "Visible", TRUE);
Because SetPropChar and SetPropBOOL are fully supported by WebNavigator, the pop-up opens cleanly inside the browser viewport.

Supported vs Unsupported Function Matrix in WinCC WebNavigator V7.4

The following table categorizes window management functions by WebNavigator compatibility:

WinCC API FunctionCategoryDesktop WinCC RuntimeWebNavigator ClientTechnological Alternative for WebSSMRTOpenTopField2Split Screen ManagerSupportedNOT SupportedEmbedded Picture Window (SetVisible)SSMOpenTopFieldSplit Screen ManagerSupportedNOT SupportedEmbedded Picture Window (SetVisible)SetVisible / GetVisibleStandard PropertySupportedSupportedPrimary method for showing/hiding web dialogsSetPictureNameStandard PropertySupportedSupportedDynamically rebinds PDL template to containerOpenWebFaceplateAPL Web APISupportedSupportedNative APL faceplate handler for web clientsSetTagPrefixTag ManagementSupportedSupportedBinds structure prefix to container dynamically

Step-by-Step Procedure to Implement Web-Compatible Pop-Up Windows

Follow this configuration procedure to enable reliable pop-ups across both desktop and web clients:

Publish Graphic Files: In WinCC Explorer, open the Web View Publisher. Ensure the target faceplate (e.g. @PG_C_DRV_1D.PDL) and all sub-pictures are successfully published without compilation errors.
Insert Picture Window: Open the process picture in Graphics Designer. Insert a Picture Window object named PopUp_Window.
Configure Window Properties: Set Border: Yes, Title Bar: Yes, Close Box: Yes, Visible: No, Adapt Size: Yes.
Attach Click Action to Object Icon: On the block icon's mouse click event, add the Web-compatible C-action:
c SetPictureName(lpszPictureName, "PopUp_Window", "@PG_C_DRV_1D.PDL"); SetTagPrefix(lpszPictureName, "PopUp_Window", "M101."); SetVisible(lpszPictureName, "PopUp_Window", 1);
Configure Close Button: In the picture window or child PDL, connect the close button to SetVisible(lpszPictureName, "PopUp_Window", 0).
Publish Process Screen: Re-run the Web View Publisher on the modified plant graphic.
Test in Browser: Open the screen in Internet Explorer on the Web client and click the icon to verify the pop-up opens.

Verification

Verify pop-up functionality using these steps:

Web Browser Click Test: Open Internet Explorer on a remote PC connected to WebNavigator. Click the drive symbol; verify the pop-up appears.
Data Binding Validation: Verify that live process values, alarms, and drive modes populate inside the pop-up without lag.
Close and Reposition: Confirm the pop-up can be dragged within the browser canvas and closed cleanly via the 'X' box.
Web Diagnostic Log: Check C:\Program Files (x86)\Siemens\WinCC\Webnavigator\Client\log\ on the client PC; confirm zero function errors.

Limitations and Operational Precautions

Observe the following technical precautions:

Browser Viewport Constraints: A WebNavigator pop-up window cannot be dragged outside the boundaries of the Internet Explorer browser window.
ActiveX Sandbox Execution: Do not attempt to call Windows Win32 API functions (FindWindow, SendMessage) from WebNavigator scripts.
Commercial Accuracy Disclaimer: Software order numbers (MLFBs), package structures, and hardware capacity prerequisites vary across PCS 7 versions and hardware platforms. System integrators must confirm exact software entitlements and licensing requirements against the official Siemens Catalog CA 01 and obtain an authorized Siemens distributor quotation prior to purchasing.

Engineer FAQ

Can a pop-up window in WebNavigator be dragged across dual monitors?

Only if the web browser window itself spans across both physical monitors; WebNavigator cannot float child windows outside the parent browser application.