Configuring Alarm Sorting in WinCC Professional TIA Portal

WinCC Professional (TIA Portal) inherits the same alarm control object model and VBS interface as Classic WinCC V7.x, but exposes the underlying sort properties through different dialog paths. The most common field requirement is a runtime-stable sort that places unacknowledged errors at the top, warnings beneath them, and acknowledged events at the bottom. This reference documents the configuration path, the VBS properties that govern scroll behavior on sort, and the verification steps required to confirm deterministic sort order in Runtime.

1. Problem Scope and Engineering Objective

Operators expect alarm lists to behave as decision support, not as a chronological log. A deterministic sort order reduces cognitive load and shortens the time-to-acknowledge for high-priority events. The engineering objective is to:

• Place unacknowledged alarms at the top of the visible list.
• Order remaining alarms by class (Errors, Warnings, Messages) when acknowledged state is equal.
• Prevent the control from automatically scrolling to the newest event when a sort key is applied.
• Persist the configuration in the engineering station (ES) rather than relying on runtime configuration.

WinCC Professional does not expose every property through the Properties inspector in TIA Portal. Specifically, the IgnoreAutoScrollOnSort flag that controls the runtime behavior of the sort command is a member of the Alarm Control's VBS object model and must be set through a script or the runtime sort dialog.

2. Prerequisites

3. Alarm Control Object Model Overview

The Alarm Control in TIA Portal WinCC Professional exposes the same COM-style object model used in Classic WinCC V7.x. The two members relevant to sort control are:

• MessageColumnSortIndex — sets the index of the column used as the primary sort key. Accepts the column index as a 1-based integer.
• IgnoreAutoScrollOnSort — boolean flag that, when set to True, prevents the Alarm Control from jumping to the most recent alarm when the sort key changes.

Both members are accessible from VBS through the screen object's HMIRuntime path. The dialog-based sort configuration (Properties > Columns > Sort) writes to the same internal data set, but does not expose IgnoreAutoScrollOnSort; that property is reachable only through the runtime sort dialog or through VBS.

4. Step-by-Step Configuration in the Engineering Station

The following procedure produces a stable sort in Runtime without resorting to runtime configuration. All settings persist in the project and are deployed with the HMI image.

4.1 Disable Automatic Scrolling

1. Select the Alarm Control on the screen.
2. Navigate to Properties > Window > Scrolling.
3. Set the Scrolling property from Automatic to Manual (or disable Follow-up scrolling as available in your version).

This step is mandatory. With automatic scrolling enabled, the control repositions the selection on the newest event after every refresh, masking the sort effect.

4.2 Enable the Required Alarm Blocks

1. Open Project settings > Alarm blocks.
2. Enable the system blocks Alarm Class and Acknowledgment. The Acknowledgment block is required because it carries the boolean state that drives secondary sort.
3. Alternatively, enable the same blocks per control under Properties > Blocks. The per-control setting overrides the project setting for that instance only.

4.3 Expose the Sort Columns

1. Open Properties > Columns for the Alarm Control.
2. Add the columns Alarm Class and Acknowledgment to the visible column set.
3. Reorder the columns so the operator sees the sort key at the leading edge of the table. A typical layout is: Date/Time, Alarm Class, Acknowledgment, Message text, Area, Source.

4.4 Configure Sort Order and Direction

1. Return to Properties > Columns.
2. For the Alarm Class column set:
   • Sort order: 1 (primary key)
   • Sort direction: Ascending
3. For the Acknowledgment column set:
   • Sort order: 2 (secondary key)
   • Sort direction: Descending

With Alarm Class ascending and Acknowledgment descending, the Alarm Control first orders by class (Errors at the top because Errors < Warnings < Messages in numeric class ID), and within each class groups unacknowledged entries above acknowledged ones. The result is the desired operator-priority list.

5. Handling IgnoreAutoScrollOnSort

The dialog-based sort in TIA Portal does not surface the IgnoreAutoScrollOnSort property. There is no equivalent field in Properties > Columns or Properties > Window. To control this behavior, use one of the following approaches.

5.1 Runtime Sort Dialog

The runtime sort dialog — the same dialog present in Classic WinCC V7.x — exposes the Ignore auto scroll checkbox. Operators can toggle it interactively. This is the path of least resistance when the project allows operator-driven sort configuration, but it does not persist across recompile unless captured by a script.

5.2 VBScript on Screen Load

Attach the following VBS procedure to the screen's Loaded event. The script writes both MessageColumnSortIndex and IgnoreAutoScrollOnSort through the Alarm Control's Item collection.

' VBS - attach to Screen "AlarmOverview" Loaded event
Sub Screen_Loaded()
    Dim objAlarmCtrl
    Set objAlarmCtrl = ScreenItems("Control1")

    ' Disable automatic scroll on sort
    objAlarmCtrl.IgnoreAutoScrollOnSort = True

    ' Optional: enforce column-based sort from script
    objAlarmCtrl.MessageColumnSortIndex = 2   ' column 2 = Alarm Class
    objAlarmCtrl.MessageColumnSortMode   = 1   ' 0 = ascending, 1 = descending

    ' Optional: clear the operator's runtime sort override
    objAlarmCtrl.MessageColumnSort = False
End Sub

The ScreenItems("Control1") reference is the HMI tag name of the Alarm Control as defined in Properties > General > Name. Replace Control1 with the actual control name in your project.

5.3 Dynamic Toggle on a Button

Bind a button's Click event to a procedure that flips the property and refreshes the view:

Sub OnClick(ByVal Item)
    Dim objAlarmCtrl
    Set objAlarmCtrl = ScreenItems("Control1")

    objAlarmCtrl.IgnoreAutoScrollOnSort = Not objAlarmCtrl.IgnoreAutoScrollOnSort

    ' Force a refresh so the operator sees immediate feedback
    objAlarmCtrl.MessageColumnSort = True
End Sub

6. Alarm Logging Configuration (RT Professional)

The alarm logging subsystem records all configured events. The Alarm Control reads from this log, so the sort keys must exist as columns in the configured log. Confirm the path:

1. Open HMI tags > Alarm logging on the HMI device.
2. Verify the active log contains columns for Class, State (acknowledgment), and Time.
3. If your project uses a custom log layout, add the missing columns or switch back to the system log layout.

Reference: Basics on alarm logging (RT Professional) — TIA Portal V20 documentation.

7. Verification Procedure

After deploying the project to the RT Professional runtime, validate the configuration with the following checks.

7.1 Functional Check

1. Trigger an Error alarm in slot A and a Warning alarm in slot B, both unacknowledged.
2. Trigger a Warning alarm in slot C, acknowledged.
3. Confirm the visible list order, top to bottom: Error A (unacknowledged), Warning B (unacknowledged), Warning C (acknowledged).
4. Acknowledge Error A and confirm it remains above Warning C (Alarm Class sort key is unchanged).

7.2 Scroll Behavior Check

1. With the list populated, change the sort order at runtime through the sort dialog.
2. Confirm the selection does not jump to the most recent event when IgnoreAutoScrollOnSort = True.
3. Toggle the property via the dynamic button (Section 5.3) and confirm the behavior reverses when False.

7.3 Persistence Check

1. Stop and restart the Runtime.
2. Confirm the column set, sort order, and direction persist (TIA Portal-written configuration is part of the project image).
3. Confirm IgnoreAutoScrollOnSort returns to its last scripted value. The runtime sort dialog's checkbox does not persist across restart unless written from a script attached to Screen_Loaded.

8. Comparison: TIA Portal vs Classic WinCC V7.x

9. Troubleshooting Matrix

10. Best Practices for Production Projects

• Prefer script-driven configuration for non-visual properties. Properties like IgnoreAutoScrollOnSort cannot be set through the TIA Portal inspector; using a single Screen_Loaded VBS function keeps the configuration reproducible across recompiles.
• Lock operator sort changes through UAC. Disable the sort button on the Alarm Control toolbar if your plant requires deterministic list behavior.
• Use distinct sort order values. Multiple columns with the same sort order value cause undefined prioritization in WinCC Professional.
• Document the column index in script headers. VBS sort index references are positional; if the operator's column layout is edited, the script breaks silently.
• Validate the alarm log schema before commissioning. A missing Acknowledgment system block in the log layout is the most common source of "sort key does nothing" complaints.
• Test under alarm flood. Sort performance under 100+ events/second is dominated by the alarm log read path, not the sort itself. Profile with the WinCC Channel Diagnosis tool before sign-off.

11. Reference: Related Configuration Paths

• Basics on alarm logging (RT Professional)
• Configuring columns and sorting (RT Unified) — note that RT Unified uses a different JavaScript-based API; properties documented here apply to RT Professional.