Calculating Daily Total Alarms per Area in CEMAT and Configuring Popup Alarm Lists in SIMATIC PCS 7

To calculate and display the total number of alarms generated per day per plant area in SIMATIC PCS 7 with CEMAT (bypassing the 1,000-alarm active buffer limit of standard alarm screens), implement the WinCC AlarmControl in Hit List / Statistics mode or deploy SIMATIC Information Server. In WinCC Graphics Designer, configure a dedicated picture window containing the WinCC AlarmControl, filter the alarm selection by the target plant area and a rolling 24-hour time range, and set the display mode to 'Hit List' to view total alarm occurrences. To make the CEMAT alarm list a floating popup display, encapsulate @C_AlarmList.pdl inside a WinCC picture window with the 'Window' and 'Closable' attributes enabled.

Alarm Buffer Limitations in Continuous Process Environments

In large industrial plants (such as cement kilns, power stations, and refineries), thousands of alarms can be generated across multiple plant areas during operational upsets. Plant managers and operations supervisors require daily key performance indicators (KPIs), specifically Total Alarms Generated per Day per Area, to identify bad-actor instruments and comply with EEMUA 191 / ISA 18.2 alarm management standards.

Engineers frequently hit a barrier with the standard CEMAT alarm list screen: the runtime view is hardcoded to display a maximum of 1,000 active alarms in its scrollable list. If a major disturbance occurs, older alarms scroll out of the active view, making manual tallying impossible.

Calculating Daily Alarm Counts: WinCC Alarm Hit List Statistics

SIMATIC WinCC includes a built-in statistical aggregation engine inside the WinCC AlarmControl:

Hit List Display Mode: Unlike the standard Message List (which shows chronological sequences), the Hit List groups messages by alarm tag and displays the Number of Occurrences (Frequency) over a defined time window.
Area Filtering: In the control properties, apply a filter criteria: Area = 'RawMill' (or select the specific plant hierarchy folder).
Time Range Filter: Set the time filter to Relative Time Range: Last 24 Hours (or fixed calendar day 00:00:00 to 23:59:59).
Total Count Display: The status bar of the AlarmControl displays the sum total of all alarm events recorded within that area during the 24-hour period.

Enterprise Reporting: Using SIMATIC Information Server for Daily KPI Audits

For formal management reporting, the recommended Siemens solution is SIMATIC Information Server (IS) connected to the Process Historian or OS Server Tag/Alarm archive:

IS provides predefined Alarm Hit List and Alarm Summary report templates.
The report can be scheduled to compile automatically at midnight, calculating the total alarm count for each plant area.
Reports are automatically exported to PDF or Excel and emailed to plant managers.

Configuring the CEMAT Alarm List as a Floating Popup Window

By default, the CEMAT Alarm List loads as a full-screen replacement picture, displacing the operator's current process graphic. To configure it as an on-demand floating popup window:

Open the parent overview picture or navigation template (@TOP.PDL / @SCREEN.PDL) in Graphics Designer.
Insert a Picture Window object from Smart Objects. Name it PicWin_AlarmList.
Set Picture Name to @C_AlarmList.pdl (or the customized CEMAT alarm screen).
Configure window properties:

Visible = False (Hidden initially)
Movable = True
Closable = True
Title = True ('CEMAT Area Alarm Summary')

In the toolbar button C-script, replace the standard screen change command (ChangePicture) with a visibility toggle: SetVisible(lpszPictureName, "PicWin_AlarmList", TRUE);.

Alarm Analysis Method Comparison Matrix

The following table compares methods for calculating daily alarm counts in PCS 7:

Analysis ToolData SourceMax Events EvaluatedAutomatic Email / ExportOperator ImpactStandard CEMAT Alarm ListShort-term OS memory buffer1,000 alarms maxNODisplaces current process pictureWinCC AlarmControl (Hit List)Short-term SQL Alarm ArchiveTens of thousandsManual export to CSVIntegrated into custom popup pictureSIMATIC Information ServerLong-term Process HistorianUnlimited historical archiveYES (Automated PDF/Excel)Zero load on live OS runtime serversSQL Server Reporting (Custom)WinCC SQL database tablesUnlimitedConditional (SSRS scheduler)Requires database query administration

Verification

Verify alarm tallying and popup operation through the following steps:

Open WinCC Runtime on an OS Client. Click the newly configured 'Alarm Summary' button.
Verify that the alarm window opens cleanly as a floating, movable popup window above the active process screen.
Select the Hit List tab. Confirm that alarms are grouped with occurrence counts displayed for the last 24 hours.
Filter by Area (e.g., 'Area_Kiln'). Confirm that the status bar displays the exact total alarm count for that area.
Close the popup window using the title bar 'X' button; confirm that the underlying process graphic remains active and undisturbed.

Limitations and Operational Precautions

Consider these operational rules when querying alarm statistics:

SQL Workload Precaution: Querying millions of historical alarm records over broad multi-month time spans from a live OS Server can freeze the SQL Server instance; execute heavy statistical queries on SIMATIC Information Server / Process Historian.
Alarm Flooding Compliance: Under ISA 18.2 standards, an operating area generating more than 10 alarms per 10 minutes is classified as an 'Alarm Flood'; use the hit list to identify bad-actor chattering sensors for alarm rationalization.
Popup Window Layering: Ensure the picture window has a high Z-order (display layer) so it does not hide behind active process faceplates.

Engineer FAQ

What is the difference between Message List and Hit List in WinCC AlarmControl?

The Message List displays alarms chronologically as individual incoming/outgoing events. The Hit List groups identical alarms together, displaying total frequency and duration.