Exporting Alarm Hit List and Sequence Reports from Process Historian via SIMATIC Information Server

In SIMATIC PCS 7, the Process Historian (PH) server operates as a centralized Microsoft SQL Server archive repository and does not contain a built-in user interface for direct report generation or data export. To generate, display, and export alarm hit lists (such as Top 10 most frequent alarms, alarm duration, or chattering messages) from Process Historian archives, engineers must deploy SIMATIC Information Server (IS). Information Server connects to Process Historian, queries the historical message database, and formats the data using pre-configured alarm report templates. Reports can be previewed in a web browser, scheduled automatically, or exported directly into PDF, Microsoft Excel (XLSX), Word (DOCX), or CSV formats.

Architecture of Process Historian and Information Server

In modern SIMATIC PCS 7 architectures (v8.0 through v9.1), long-term plant archiving and regulatory reporting are decoupled into two distinct server components:

flowchart LR
    A["WinCC OS Servers<br/>(Local Short-Term Archive)"] -- "Continuous Non-Cyclic Push" --> B["Process Historian (PH)<br/>(Central MS SQL Database)"]
    B -- "SQL Queries / OLE-DB" --> C["SIMATIC Information Server (IS)<br/>(Web & Reporting Engine)"]
    C -- "Web Portal / Automated Dispatch" --> D["Corporate Intranet / PDF / Excel / CSV Reports"]

Process Historian (PH): Operates as the central, high-performance long-term archiving system. It runs Microsoft SQL Server enterprise database engines and continuously ingests real-time process values, batch archives, and alarm messages from multiple WinCC OS Servers.
SIMATIC Information Server (IS): Operates as the reporting and visualization engine. Based on Microsoft SQL Server Reporting Services (SSRS) and web technologies, Information Server connects directly to Process Historian, executes analytical queries, and renders standardized reports.

Why Process Historian Cannot Generate Reports Directly

A frequent point of confusion among plant engineers is attempting to log into the physical Process Historian server desktop expecting an interactive export utility or report generator.

Process Historian intentionally omits direct reporting tools:
- Database Performance Protection: Process Historian is optimized for high-throughput, continuous write operations from dozens of OS servers. Running heavy statistical queries, report rendering engines, and desktop applications directly on the PH database host threatens database ingestion throughput and can cause OS server buffer overflows.
- Role Decoupling: Process Historian functions as a hardened, headless database repository. All data extraction, user authentication, report scheduling, and web presentation are offloaded to SIMATIC Information Server (which can reside on a separate physical server, virtual machine, or be co-located with IS on smaller installations).

Configuring Alarm Hit List Reports in Information Server

To generate and export an Alarm Hit List report (documenting the most frequent alarms, chattering alarms, and total alarm durations):

Step 1: Access the Information Server Web Portal

Open a web browser (e.g., Microsoft Edge or Google Chrome) on any network-connected workstation.
Navigate to the Information Server URL: http://<InformationServer_Hostname>/InformationServer.
Log in using authorized Windows domain or local user credentials.

Step 2: Select the Alarm Report Template

In the Information Server left navigation pane, select Reports.
Expand the Message or Alarm category.
Select the pre-configured template: Alarm Hit List (or Message Hit List).

Step 3: Configure Query Parameters

In the report parameter configuration panel:
1. Data Source: Select the linked Process Historian database.
2. Time Range: Define the evaluation period (e.g., Last 24 Hours, Previous Week, or Custom Time Range).
3. Filter Criteria:
- Filter by Plant Hierarchy Area (e.g., Plant1/UnitA).
- Filter by Message Class (e.g., Alarm - High, Warning).
- Set the Top N threshold (e.g., Top 10 or Top 20 most frequent alarms).
4. Sort Order: Choose to rank by Frequency (Number of Occurrences) or Total Accumulated Duration.

Step 4: Preview and Export

Click View Report to generate the graphical and tabular report on screen.
Review the Pareto chart showing the top chattering alarms and the summary statistics table.
In the top toolbar, click the Export dropdown menu.
Select the desired export format: PDF, Excel (.xlsx), Word (.docx), or CSV. The file is generated and downloaded immediately.

Standard Information Server Alarm Report Templates

SIMATIC Information Server provides standardized report templates compliant with EEMUA 191 and ISA-18.2 alarm management guidelines:

Template NamePrimary Data ContentAnalytical PurposeStandard Export FormatsAlarm Hit ListTop $N$ most frequent alarms, occurrence count, percentageIdentifies chattering tags and bad actors causing operator overloadPDF, Excel, CSVAlarm Duration ListAlarms ranked by cumulative time in active/unacknowledged stateIdentifies chronic unaddressed process faults and stagnant alarmsPDF, ExcelMessage SequenceChronological audit trail of all messages with millisecond timestampsRoot cause analysis following an automated plant tripPDF, Excel, CSVOperating MessagesLog of operator actions, setpoint changes, and mode togglesAudit trail for operational compliance and forensic reviewPDF, Word, ExcelAlarm DistributionHourly/daily alarm count histograms plotted against target ratesVerifies compliance with ISA-18.2 targets (< 10 alarms / hour)PDF, Excel

Verification

To confirm that alarm reports are properly extracted and exported:
1. In the Information Server web portal, generate an Alarm Hit List for the previous 24-hour shift.
2. Verify that the total alarm count matches the alarm log totals recorded in WinCC Alarm Logging for that period.
3. Export the report to Excel (.xlsx).
4. Open the exported spreadsheet: Verify that column headers (Message Number, Tag Name, Event Text, Occurrences, Duration, Area) are fully populated without missing data cells.
5. In Information Server, configure a test Subscription / Schedule to dispatch the Alarm Hit List report via email or save to a file share at midnight; verify that the scheduled report file arrives in the designated folder.

Limitations and Operational Precautions

Observe the following engineering precautions when using Process Historian and Information Server:
- Report Query Execution Window: Generating reports spanning massive historical windows (e.g., 1 year of continuous alarm data across 50,000 tags) places intense I/O loads on the SQL database. Restrict on-demand queries to reasonable ranges (e.g., daily or weekly shifts) and use scheduled off-peak batches for monthly aggregates.
- Time Synchronization: Ensure Process Historian, Information Server, and all OS Servers are synchronized to a common UTC time master. Mismatches between local time zones and UTC result in skewed query intervals.
- Licensing Requirements: Information Server requires client access licenses (Information Server Client CAL) based on the number of concurrent reporting sessions or automated subscriptions.

Engineer FAQ

Can I query the Process Historian SQL database directly using SQL Server Management Studio (SSMS)?

While possible for advanced DBAs, Siemens strongly discourages direct SQL queries on production PH databases during runtime. Direct SELECT queries can lock database tables, and any manual INSERT or UPDATE statements will corrupt the proprietary archive schema and void system support.

What is the difference between WinCC IndustrialDataBridge and Information Server?

IndustrialDataBridge (IDB) is an automated data pump used for cyclic point-to-point data exchange (e.g., writing specific tag values to CSV or external databases every hour). Information Server is an enterprise reporting platform that generates formatted, analytical PDF/Excel reports from historical big data.

Do I need to install Information Server on the same physical PC as Process Historian?

No. On medium to large installations, Siemens best practices recommend installing Information Server on a separate dedicated server to prevent reporting workloads from impacting Process Historian data ingestion.