Checking HMI Tag Count in WinCC Flexible and Unified

Overview

Siemens HMI engineering tools have evolved across three major generations: ProTool (legacy, 1990s–2000s), WinCC flexible (2004–2018), and the TIA Portal-based WinCC Comfort/Advanced/Professional and WinCC Unified lines (2018–present). Each generation handles tag accounting differently. ProTool exposed the tag count in the status bar of the tag editor. WinCC flexible hides the total behind the device's Properties dialog. WinCC Unified surfaces the same metric through Runtime settings → General → Screen → Show limits of tags, with a dedicated panel that displays the configured limit, the value range, and the current usage. This article documents all three paths, the licensing model behind "power tags," and the practical commissioning checks you should perform before signing off a project.

Prerequisites

• WinCC flexible 2008 SP5 or later installed on the engineering station (SP5 is the last released service pack for the WinCC flexible 2008 line; subsequent updates were distributed as HSPs).
• TIA Portal V17, V18, V19, V20, or V21 for WinCC Unified or WinCC Comfort/Advanced/Professional workflows.
• A compiled project (.hmi or .ap* container) so that the tag counters are populated. A project that has not been compiled will show "0 / n" because no usage data has been generated.
• Read access to the project tree in the engineering tool.

Method 1 — WinCC flexible: Device Properties

This is the canonical answer to the long-standing forum question about locating the tag count when the project tree is heavily foldered and the output window is suppressed by compile errors. The total appears as a single integer on the Properties tab of the HMI device, not in any tag-editor sub-window.

1. Open the WinCC flexible project in the WinCC flexible 2008 ES.
2. In the project tree on the left, locate the device node. The default name is Device_1 but it may have been renamed to match the panel model (for example, TP1200_Comfort or MP377_15Touch).
3. Right-click the device node. The context menu appears with options including Rename, Compile, Compile and Check Consistency, and Properties.
4. Select Properties. The properties dialog opens with a vertical tab list on the left side.
5. Navigate to the Tags section. The dialog displays:
   • Total power tags used in the project
   • Tags configured for logging (subset of power tags)
   • Number of alarms (external + internal)
   • Number of screens, scripts, and schedules
6. Close the dialog. The integer is read-only and updates on the next successful compile.

Method 2 — WinCC Unified: Runtime Settings Tag Limits

WinCC Unified (TIA Portal V17 and later) introduces an explicit tag-limit panel that is accessible in the engineering tool, not just at runtime. This panel is documented in the Siemens TIA Portal Help for V21 under the topic Showing limits of tags (RT Unified).

1. Open the WinCC Unified project in TIA Portal.
2. In the project tree, expand the HMI device node.
3. Double-click Runtime settings under the device. The Runtime settings editor opens in the main work area.
4. In the navigation pane of the editor, select General → Screen.
5. Locate the Show limits of tags group. Three options are available:
   • Off — Tag limit display is suppressed in Runtime (default in projects migrated from WinCC flexible).
   • Customized — The operator sees a configurable range defined by From and To values entered in the adjacent input fields. This is the recommended setting during commissioning and FAT.
   • Full — Displays the entire configured tag count range with no operator-side filtering.
6. Set the mode to Customized and enter a representative range, for example From = 0, To = 500 on a 512-tag license.
7. Compile the project. After a successful build, the Runtime tag panel shows current usage as n / To.

Tag Limit Behavior by Panel Family

Method 3 — WinCC Comfort/Advanced: Tag Statistics in Project Properties

For TIA Portal projects that use WinCC Comfort or WinCC Advanced (the line that succeeded WinCC flexible for Compact/Comfort Panels), the consolidated tag count is reported in Project properties → Runtime → Tag statistics after a full compile.

1. Open the project in TIA Portal.
2. Right-click the project node in the project tree and select Properties.
3. In the project-properties dialog, click Runtime in the left column.
4. Click the Tag statistics sub-entry. The dialog shows three columns: Total tags, Power tags, Tags in use.
5. Note the Tags in use figure. This is the number that must not exceed the licensed power-tag count.

This view is convenient when comparing multiple HMI devices within the same TIA project, because the dialog lists all configured devices in a single table.

Step-by-Step: Commissioning Tag-Count Verification

Run this procedure on every panel or PC runtime before the customer-acceptance test. It is intentionally short so that it can be executed in under five minutes per device.

1. Compile clean. Build the project to zero errors and zero warnings. Record the compiler's "Number of power tags used" line in the build log.
2. Open device properties. In WinCC flexible, follow Method 1. In WinCC Unified, follow Method 2 and enable Show limits of tags = Customized with a range that matches the licensed tier.
3. Compare three numbers.
   • Number reported by the engineering tool.
   • Number reported on the panel at runtime (visible on the configured tag-limit screen).
   • Number in the license audit (start WinCC Unified on the panel, open System → License information).
   All three must match. A mismatch indicates that the project was last edited in a different ES installation and has not been fully recompiled.
4. Reserve headroom. Document the count and leave at least 15 % unused capacity for late-stage change requests. For a 256-tag license, plan for no more than 217 power tags.
5. Sign off. Archive the screenshot of the tag-limit display and the ES-generated build log with the project's FAT report.

Tag-Count Diagnosis Matrix

Tag Export for Off-Line Audits

When the customer requires a tag-by-tag breakdown for change-control or cybersecurity review, neither WinCC flexible nor TIA Portal exposes a per-folder counter. The supported workflow is an export to CSV.

1. In WinCC flexible: Project → Export → Tags. Choose the desired tag class (all, external, internal) and the destination folder.
2. In TIA Portal (WinCC Comfort/Advanced): Open the HMI tag table, then Edit → Export to XLSX or CSV.
3. In WinCC Unified: Open the HMI tag table, right-click the table header, and select Export. CSV is the recommended format for downstream tooling.
4. Open the file in any spreadsheet tool and create a pivot table on the Connection column to count tags per PLC, or on the Folder column to count tags per engineering folder.

PowerTag Licensing Mechanics

Siemens licenses HMI external tags on a graduated scale. The price increments are coarse, so it is worth choosing the tier that covers the design point plus a 15–20 % reserve, then planning for PowerPack upgrades only when a major scope change occurs.

PowerPack upgrades are sold as a license-key delta (for example, upgrading from 128 to 512 on a TP1200 Comfort). They are written to the panel's license container via the Automation License Manager (ALM) and are recognized on the next Runtime start.

Cross-Generation Migration Notes

Engineers frequently port projects from WinCC flexible to TIA Portal (WinCC Comfort/Advanced) or to WinCC Unified. The migration preserves tags but changes the counter location, which catches first-time migrators off guard.

• WinCC flexible → WinCC Comfort/Advanced: After the migration wizard runs, the tag counter is empty until you explicitly compile the HMI device. Open the device editor, right-click the device, and select Compile → Software (only). The number then appears in Project properties → Runtime → Tag statistics.
• WinCC Comfort/Advanced → WinCC Unified: The first compile populates the Runtime settings → General → Screen → Show limits of tags panel. The panel is disabled (greyed out) until the compile completes, so do not interpret a greyed-out panel as a configuration error.
• ProTool → WinCC flexible: The ProTool status-bar count is not migrated. Engineers must use the device Properties dialog as described in Method 1.

Verification Checklist

• [ ] Project compiles to zero errors and zero warnings.
• [ ] WinCC flexible: Device Properties → Tags shows the expected power-tag total.
• [ ] WinCC Unified: Runtime settings → General → Screen → Show limits of tags is set to Customized with the licensed range.
• [ ] Runtime on the panel reports a tag count that matches the engineering tool within ±1.
• [ ] Exported CSV tag list reconciles with the engineering tool count when pivoted by Connection.
• [ ] 15 %–20 % unused capacity remains below the licensed power-tag tier.

FAQ