Embedding Trend Views in TP1500 Comfort HMI Reports

Including a live trend view or a bitmap snapshot of an active trend in a scheduled or event-driven HMI report on a SIMATIC TP1500 Comfort panel paired with an S7-1200 CPU 1214C is a recurring engineering requirement. The SIMATIC Comfort Panel runtime does not expose the trend view object as a reportable element the way WinCC Runtime Professional does, so the standard "drop the trend into a report template" approach fails. This reference documents why the limitation exists, what is officially supported in TIA Portal V17 through V21, and which workarounds produce deterministic, auditable output on a TP1500 Comfort panel.

1. System Identification and Engineering Environment

Before configuring reports, confirm the exact catalog numbers and firmware combination. The runtime behaviors of the report designer, the VBScript engine, and the trend view depend on the TIA Portal version used to compile the HMI project and the panel image version installed on the TP1500.

2. Architecture: How Reports Work in a Comfort Panel

The WinCC Comfort report system is a server-side subsystem inside the HMI runtime. It consumes data from logged tags, archives, recipe data, alarm logs, and a small set of object types that the runtime can serialize into the report template at runtime. The architecture is intentionally different from WinCC RT Professional.

The report designer in TIA Portal exposes a fixed set of objects that can be placed on a report template. For Comfort panels these include tag tables, archive tables, alarm views, I/O fields, texts, date/time fields, and graphic I/O fields. The trend view object that you can place on a process screen is not a member of this object set on Comfort panels. The "Control Hardcopy" object, which is a different system object that is bound to a screen and prints the visible contents of that screen into the report, is documented in the WinCC V17 manual and subsequent versions, but it is restricted to WinCC Runtime Professional. A Comfort panel ignores or refuses to compile a Control Hardcopy placed in a report template.

Reference: WinCC V17 manual — Working with Reports (TIA Portal Help entry 109798671).

3. Why the Trend View Cannot Be Embedded Directly

The runtime is built around a strict separation between interactive screen objects and reportable data sources. The trend view on a process screen is rendered by the screen manager and lives in a graphical layer; the report designer only resolves pointers to logged values, not to graphical widgets. Two specific limits apply:

1. No trend widget in the report toolbox. The Comfort report object palette does not include a "Trend view" or "f(x) trend view" object. The f(x) trend view is documented for WinCC Runtime Professional and PC-based systems; see the TIA Portal help f(x) trend view in reports (RT Professional).
2. No Control Hardcopy on Comfort. Control Hardcopy is a runtime object that targets a named screen on a Professional runtime and rasterizes the current contents. The Comfort runtime does not implement the same object model, so a Hardcopy reference compiles as a placeholder or is rejected.
3. VBScript cannot serialize a live trend widget. The VBScript host on a Comfort panel (since V14 SP1) can read and write tags, control the screen, call HMIRuntime functions, and use the screen item collection only for the items exposed on the current screen. It does not expose a method to capture the raster image of a trend view as a portable bitmap that can be re-rendered into a report.

The combination of these three constraints is what motivates the workarounds below. The next sections walk through each approach in order of engineering cost.

4. Workaround A — PrintScreen Function (Lowest Cost)

The PrintScreen function is built into the Comfort panel firmware. It captures the currently displayed screen as a PNG bitmap and either prints it to a configured printer, or — more usefully for report workflows — saves it to a USB stick, a network share, or a local path on the panel file system. The print/save trigger is fired by an event, a button, or a scheduled job.

Reference: PrintScreen function on SIMATIC Panels (Entry ID 58205602).

4.1 Enabling PrintScreen in the project

1. In TIA Portal, open the HMI device configuration for the TP1500.
2. Navigate to Runtime settings > Screen > Print (or Printer settings on newer TIA versions).
3. Enable PrintScreen function and select the output target: Network printer, USB printer, or file export.
4. For PDF or file workflows, configure the storage path under Storage media. The panel supports SMB network shares (\\server\share\folder) and the local /media/simatic/<USB> path.
5. On the screen that contains the trend, place a button and wire the Press event to the system function PrintScreen.

4.2 Scheduled PrintScreen for trend reports

The PrintScreen function can be triggered by the scheduler. Combine the scheduler with a screen change to make sure the panel is on the trend screen when the capture fires.

1. Open Schedules in the HMI project tree.
2. Create a new trigger, e.g. "Daily_Trend_Report" with the desired cycle (every 5 minutes, shift change, etc.).
3. Add the events:
   — ActivateScreen with screen name Trend_Overview
   — PrintScreen with output configured for PDF or file

4.3 Page-format parameters

5. Workaround B — VBScript Screen Capture with HMIRuntime

For a fully automated, dynamic workflow that does not require operator intervention, VBScript can be used to drive the panel through the sequence "change screen → wait for redraw → call PrintScreen → notify the controller". This keeps the capture on the panel and does not depend on a separate PC, but it inherits the landscape-output limitation of PrintScreen.

5.1 VBScript on a scheduled task

Place this script in a function block on the HMI and call it from a scheduler event. It uses the public VBScript APIs that have been available on Comfort panels since TIA V14 SP1.

'==========================================================
' TrendReport_Capture.vbs
' Purpose: switch to the trend screen, printscreen it as a
' named PDF file, then return to the home screen.
' Tested: TIA V17 SP1 / V18 / V19 / V20 / V21 with
'         TP1500 Comfort image 17.0.0.x through 21.0.x
'==========================================================
Const HOME_SCREEN   = "Screen_Home"
Const TREND_SCREEN  = "Screen_TrendOverview"
Const REPORT_DIR    = "\\\\nas01\\hmi\\reports\\"
Const FILE_PREFIX   = "Trend_"

Sub TriggerTrendReport()
    Dim sDate, sTime, sFile, sPath

    ' 1. Switch to the trend screen so the PrintScreen
    '    captures the active trend view, not the home screen.
    HMIRuntime.BaseScreenName = TREND_SCREEN

    ' 2. Build a deterministic file name from date / time.
    sDate = Year(Now) & Right("0" & Month(Now), 2) & Right("0" & Day(Now), 2)
    sTime = Right("0" & Hour(Now), 2) & Right("0" & Minute(Now), 2)
    sFile = FILE_PREFIX & sDate & "_" & sTime & ".pdf"
    sPath = REPORT_DIR & sFile

    ' 3. Configure the PrintScreen output. The SmartTag
    '    "@TrendReportTarget" can be set from the S7-1200
    '    to swap storage location per shift.
    HMIRuntime.Trace "Capturing " & sPath & vbCrLf
    HMIRuntime.PrintScreen sPath

    ' 4. Return to the home screen.
    HMIRuntime.BaseScreenName = HOME_SCREEN

    ' 5. Notify the CPU 1214C that a report is available.
    '    The PLC then reads the file via SMB or waits for
    '    a heart-beat tag increment.
    SmartTags("ReportFileName") = sFile
    SmartTags("ReportReady")    = True
End Sub

5.2 Triggering from the CPU 1214C

The S7-1200 can set a tag that the HMI polls via the standard area pointer "Coordination" or via a direct tag connection. The HMI script fires when the bit transitions 0→1. A typical SCL snippet on the CPU 1214C side:

// SCL — request a trend report from the panel
// Tags: "HMI_RequestTrendReport" (HMI boolean, write from PLC)
//       "HMI_ReportReady"         (HMI boolean, read by PLC)
//       "HMI_ReportFileName"      (HMI WString, read by PLC)

IF "RequestTrendReport" AND NOT "HMI_ReportReady" THEN
    "HMI_RequestTrendReport" := TRUE;     // edge-triggered on the HMI
ELSE
    "HMI_RequestTrendReport" := FALSE;
END_IF;

IF "HMI_ReportReady" THEN
    // Pull the file or archive the path in a string DB
    "LastReportName" := "HMI_ReportFileName";
    "HMI_ReportReady" := FALSE;
END_IF;

6. Workaround C — Migrate the Report Subsystem to RT Professional

If the application genuinely needs trend objects and Control Hardcopy in the same report, the supported path is to move the report layer to a PC runtime. The trend view and f(x) trend view are first-class report objects in WinCC Runtime Professional, so the same TIA Portal project can host a Comfort panel as the operator screen and a PC station running RT Advanced / RT Professional as the report server.

6.1 Topology

6.2 Engineering steps

1. Add a PC station to the TIA project. Right-click Project > Add new device > SIMATIC PC > WinCC Runtime Professional.
2. Select the WinCC RT Professional option (license key required, e.g. 6AV2105-xxxxx-xxxx for an RT Professional 4096 PowerTag license).
3. Reuse the HMI tag set from the TP1500 by exporting the HMI tags from the Comfort device and re-importing them on the PC station, or by configuring shared tags via a project library.
4. Build the report template on the PC station. The trend view object is now available in the report toolbox; place a trend view and a Control Hardcopy that targets the same trend screen.
5. Configure the report scheduler on the PC station to print to PDF, email, or a network share.
6. The Comfort panel remains the operator face; the PC station is invisible to the operator and acts as a silent report engine.

7. Workaround D — External Report Generation from the S7-1200 Archive

A common alternative is to log the trend tags in the S7-1200 data block or in a Comfort archive, then generate the report on a separate system that can render trends. The panel acts purely as a tag provider; the report is produced by a SCADA layer, a Node-RED server, a Python script, or a TIA-connected WinCC Unified client.

7.1 S7-1200 data log block

Use a data block with a circular buffer for high-resolution trending. A 1 kB DB with 100 records of 8 real values is a typical starting point:

// SCL — circular trend buffer (fragment)
// DB "TrendBuffer"
// 100 records, each with timestamp and 4 process values

DATA_BLOCK "TrendBuffer"
{ S7_Optimized_Access := 'TRUE' }
AUTHOR : Siemens
FAMILY : 'trend'
NAME : 'TrendBuffer'
VERSION : 0.1
  STRUCT
    Head  : INT;       // 0..99, next write index
    Count : INT;       // number of valid records
    Rec   : ARRAY[0..99] OF STRUCT
      t_ms   : DINT;   // milliseconds since cycle start
      Temp1  : REAL;
      Temp2  : REAL;
      Press  : REAL;
      Flow   : REAL;
    END_STRUCT;
END_DATA_BLOCK

On the PC side, use the open S7 communication library (snap7, libnodave, or the S7 protocol over TCP port 102) to read the DB on a schedule and render the trend in matplotlib, a Node-RED dashboard, or a WinCC Unified trend object. The WinCC Unified client supports the trend view object natively in reports, so a Unified PC runtime is the lowest-friction upgrade path that preserves the Comfort panel investment.

8. Designing the Report Template in TIA Portal

For completeness, the report template configuration steps on a Comfort panel are listed below. The template is the file that determines what each scheduled report contains.

8.1 Creating a report

1. In the project tree, expand Reports under the HMI device.
2. Double-click Add new report to create a new template.
3. Open the report in the editor; the editor opens with an A4 portrait page (the report template page size, not the screen size).
4. From the toolbox, drag the available objects: I/O field, Tag table, Archive table, Alarm view, Text field, Date/time field, Graphic I/O field.
5. For each object, configure the data source in the properties window. For an archive table, point it at the logging tag archive that contains the trend data; configure the time range (e.g. "last 1 h" or "since last report").
6. Save the report template. It is compiled into the HMI image and deployed with the project.

8.2 Triggering a report

Reports are triggered by any of:

• Scheduler — daily, weekly, minute-by-minute, shift change.
• Event (PLC tag) — boolean tag rising edge, integer threshold, bit mask.
• Function list on a button — operator-initiated ad-hoc report.

Each trigger executes a configured function list that calls PrintReport with the report name and the output target.

9. Parameter Mapping for the Common Trend-to-Report Flow

10. Verification Procedure

After deploying the report configuration to the TP1500, run a verification sequence that confirms the trend data is reaching the report and the file is being written to the expected target.

1. Force a manual report by pressing the trigger button on the panel. Confirm the panel screen changes to the trend screen first (if using the VBScript workflow).
2. Check the configured storage path for the PDF or PNG. File name pattern should match the configured prefix and the local time of the panel.
3. Open the generated file and verify the trend curve, the time stamps, and the legend values match the live process values displayed on the panel.
4. From the CPU 1214C, read the ReportFileName and ReportReady tags; they should match the file written to disk.
5. Test a scheduled trigger (e.g. 1-minute interval) and confirm the cadence of files matches the schedule.
6. Test the error path: temporarily unmap the network share. The panel should write the report to the local /media/simatic path (if configured) and the ReportReady tag should still toggle, so the PLC records the failure as a separate state.

11. Troubleshooting Matrix

12. Field-Proven Caveats

• Tag data type mismatch. A logging tag of type DInt on the S7-1200 must be matched by an HMI tag of the same type and the same length on the TP1500; a one-byte truncation silently corrupts the trend curve.
• Time zone. The panel uses its own local time for the report file name. If the panel is in UTC and the operator reads the file in local time, the file name will appear "off" by the offset. Use a time-zone-aware post-processing step or set the panel to the plant time zone.
• Storage media wear. USB sticks on industrial panels wear out. Prefer a network share for long-term trend reports; reserve USB for short-term operator exports.
• Archive size. The Comfort panel's internal archive is limited (typically 50 MB usable). Long-range trends fill the archive in days. Configure the archive's circular mode and consider an external historian for long retention.
• VBScript licensing. VBScript on Comfort panels has been licensed since TIA V14 SP1. Older panels may need a firmware update to enable the script host.

13. Decision Summary

FAQ