Restoring Missing Maintenance View Icons on Standard Library Valve Faceplate FB73

In SIMATIC PCS 7 Standard Library V7.1, the small maintenance navigation icons (such as the wrench or sub-view tabs) on the valve faceplate for FB73 (VALVE) fail to render when the active WinCC user lacks the mandatory user authorization level (Level 6: Process Controlling or Level 10: Maintenance), or when legacy faceplate support graphics (@PG_VALVE_MAINT.pdl) and C script files (s7jli*.fct) are missing from the OS project's GraCS folder. In WinCC V7.3/V7.4, faceplates dynamically hide unauthorized control icons. Assigning the proper authorization level in WinCC User Administrator and ensuring all classic Standard Library view PDLs are copied into GraCS restores full access to the Maintenance view.

Standard Library FB73 (VALVE) Faceplate Architecture

The function block VALVE (FB73) is the core technological block for controlling digital process valves in the classic SIMATIC PCS 7 Standard Library (V6.x / V7.x). When an operator clicks a valve block icon in WinCC, the supervisory system opens the multi-view faceplate container (@PG_VALVE.pdl).

The classic faceplate interface consists of multiple view panels loaded into a central picture window: the Standard View (@PG_VALVE_STANDARD.pdl), the Alarm View (@PG_VALVE_ALARM.pdl), and the Maintenance View (@PG_VALVE_MAINT.pdl). Navigation between these sub-views is controlled by a row of small toolbar buttons (icons depicting wrenches, bells, and limit lines). If these icons disappear, maintenance personnel cannot access valve travel time monitoring, limit switch monitoring overrides, or manual tracking parameters.

Root Causes of Missing Faceplate Maintenance Icons

Technical investigation reveals three primary reasons why maintenance icons vanish from FB73 faceplates in modernized engineering environments (such as CFC V8.1 and WinCC V7.3):

User Authorization Suppression: Standard Library faceplate scripts evaluate the current user's security token upon opening. If the user does not possess authorization for Level 6 (Process Controlling) or Level 10 (Maintenance), the script executes SetVisible(lpszPictureName, "btnMaint", FALSE), completely collapsing the icon.
Missing Maintenance PDL Files in GraCS: During project migrations from PCS 7 V7.1 to V8.x, the OS Project Editor updates system pictures but does not copy legacy Standard Library sub-views by default. If @PG_VALVE_MAINT.pdl is absent from the project GraCS directory, the master faceplate script fails to find the target and suppresses the button.
Communication Failure / Bad Signal Quality: If the S7 connection between the OS and the AS is disrupted, or if block inputs have bad quality codes, the faceplate enters safe mode, greying out or hiding non-essential sub-views.

Valve Faceplate Components and Authorization Matrix

The following table details the files, scripts, and user authorization levels required for FB73 faceplates:

Sub-View NameAssociated PDL FileRequired User AuthorizationKey Functions AccessibleStandard View@PG_VALVE_STANDARD.pdlLevel 5: Process ControllingOpen/Close commands, Auto/Manual toggleAlarm View@PG_VALVE_ALARM.pdlLevel 4: MonitoringAcknowledge valve runtime alarms, trip historyMaintenance View@PG_VALVE_MAINT.pdlLevel 6 or Level 10 (Maintenance)Monitor transit times, limit switch debounce, test modeTrend View@PG_VALVE_TREND.pdlLevel 4: MonitoringReal-time command and feedback signal trendsFaceplate Container@PG_VALVE.pdlLevel 4: MonitoringMaster window hosting toolbar icons and headers

Step-by-Step Procedure to Restore Maintenance View Icons

To restore the missing maintenance icons and regain access to the valve maintenance sub-view:

Configure User Permissions in WinCC User Administrator:
- In WinCC Explorer, open User Administrator.
- Select the logged-in user profile (e.g., Operator or Administrator).
- Ensure that Authorization Level 6 (Process Controlling) and Authorization Level 10 (Maintenance) are enabled with checkmarks.
- Save User Administrator changes and re-log into WinCC Runtime.
Restore Missing PDLs to the GraCS Directory:
- Locate your PCS 7 Standard Library V7.1 installation repository or original project backup.
- Copy the following files into the target OS project's GraCS directory (<OS_Path>\wincproj\<OS_Name>\GraCS\):
- @PG_VALVE.pdl
- @PG_VALVE_STANDARD.pdl
- @PG_VALVE_MAINT.pdl
- @PG_VALVE_ALARM.pdl
- All associated button bitmaps (@*.bmp).
Verify S7 Connection and Recompile OS:
- Confirm the Named Connection to the AS is healthy in WinCC Tag Management.
- Run a Changes-Only OS Compile in SIMATIC Manager to refresh block instance tag structures.
Test in WinCC Runtime:
- Open the valve faceplate in WinCC Runtime. The small wrench icon will now appear in the upper toolbar.

Verification

Verify maintenance view access:
1. Click the valve block icon in WinCC Runtime to open the faceplate.
2. Confirm that the small wrench icon is clearly rendered in the toolbar.
3. Click the wrench icon. Confirm that the faceplate switches to @PG_VALVE_MAINT.pdl without error popups.
4. Verify that maintenance parameters (such as transit time limits and monitor disable toggles) are visible and editable.

Limitations and Operational Precautions

Standard Library Obsolescence: Standard Library V7.1 is obsolete and superseded by the Advanced Process Library (APL). Blocks like FB73 lack modern APL features like preview views and maintenance bypass states.
OS Project Editor Overwrites: Never overwrite custom Standard Library faceplates with APL templates during OS Project Editor execution.
Administrative Overrides: Do not give all general plant operators Authorization Level 10, as modifying valve travel times can mask mechanical actuator binding.

Engineer FAQ

Can I upgrade FB73 to APL VlvL without changing the controller logic?

No. FB73 has an entirely different interface structure, instance DB layout, and parameter naming from APL VlvL (FB1899). Upgrading requires an AS block exchange and rewire.

Where are the classic Standard Library bitmap files located?

Bitmaps are located in the WinCC installation path under <Drive>:\Program Files (x86)\Siemens\WinCC\Options\PDL\StandardLibrary\GraCS\.

Why does the wrench icon disappear again when another operator logs in?

Because authorization is user-specific. The second operator's profile lacks Level 6 or Level 10 permissions in WinCC User Administrator.

Does FB73 support the PCS 7 Maintenance Station?

Yes, Standard Library blocks can report diagnostic alarms, but they lack the full asset management faceplate integration provided natively by APL blocks.