Patch Release Notes 3.21

Alarm Shelving and Suppression (IEC 62682)

WinCC OA now provides alarm shelving and suppression capabilities based on IEC 62682 / ISA 18.2 standards. The new AlertService enables three complementary alarm management mechanisms:

• Alarm Shelving: Operators can temporarily hide individual alert instances from the active alert list. A configurable timer automatically restores shelved alerts after the shelving period expires.
• Suppression by Design: Engineers can suppress alert handler configurations at the datapoint level to prevent alert generation during commissioning or planned maintenance.
• Out-of-Service Mode: Datapoint elements can be placed into maintenance mode by swapping alert classes to dedicated maintenance counterparts (alarm-maint, warning-maint, info-maint). Alerts continue to be generated but are visually distinguished and excluded from operational KPIs.

All actions are logged as Security Events and provide a complete audit trail. Dedicated overview panels for shelved alerts, suppressed handlers, and out-of-service objects are accessible from the Alert Event Screen.

See Alarm shelving and suppression overview for details.

WebUI Runtime

• The new WebUI Runtime provides a modern web development framework for building standalone web pages and applications on top of WinCC OA. Based on Lit Web Components and TypeScript, it connects to the backend via WebSocket using the OaRxJsApi for real-time datapoint access. Pages are served by the webserver.js and integrate seamlessly into the existing Dashboard. The framework includes a shared bundle architecture, configurable navigation, theming and branding support, and is optimized for AI-assisted development workflows. See WebUI Runtime.

CTRL

• New AlertService functions: AlertServiceClient::shelveAlerts(), AlertServiceClient::suppressAlerts(), AlertServiceClient::setOutOfService() and their corresponding reverse operations.

Disaster Recovery System

• DRS project file synchronization now uses a network share instead of shared project folders, improving security. The synchronization reuses the export path configured in the DRS wizard (Step 4) and automatically creates the subdirectories FileSync and SubFileSync on the network share. This eliminates the need for individual projects to access other project folder structures. See Configuration - Step 5 - Project File Synchronization.

Web Connectivity

• The new webserver.js backend is available as a Node.js-based web server running inside the JavaScript Manager. It provides HTTPS and WebSocket communication on a single port and serves as the recommended backend for the Dashboard and custom web applications. Customer extensions are supported via TypeScript and CTRL handlers using the @wincc-oa/backend npm package.

UI

• VarTrend: Configurable downsampling is now available for NGA projects, improving data visualization performance.
• Automatic _MemoryCheck threshold calculation now adapts dynamically to the target system hardware.

Drivers

• Modbus: The driver now supports the Output Single direction, allowing a single bit to be written to a register while all other bits are set to 0.

Northbound Manager

• Sparkplug B: The protocol now supports a configurable MQTT keep-alive timeout through the mqttkeepalive parameter in <nbm_instance>.Config.Protocol (default: 60 seconds).

Security & Authentication

• OIDC Authentication: Mobile and Desktop UIs now send only minimal information to the HTTP server during authentication, reducing exposure.
• Private Key Storage: CNG-based certificates are now supported in the web server on Windows.

Drivers

• SNMP: The config entry enableTraps can now restrict trap handling through numeric values. The legacy string values Yes and No remain supported to ensure backward compatibility.
• DNP3: The DNP3 driver now automatically performs a general query for unsolicited requests after a redundancy switchover.
• S7: The S7 driver now supports transforming S5Time to UINT, featuring the new transformation type S5TimeAsMilliseconds.
• The new SECS/GEM Gateway manager is available in WinCC OA 3.21 now

Northbound Manager

• The Northbound Manager now supports Distributed Systems. Data from remote WinCC OA systems can be published through the Northbound Interface using Plantmodel data sources. The option Incl. system name in metric name allows you to prefix metric names with the source system name, which helps to distinguish datapoints from different systems.
• The Northbound Manager now also supports the publishing of Quality data.

Manager Service API

• RPC messaging now supports encrypted payloads for the Manager Service API.

NGA

• When using NGA with a PostgreSQL® backend, DPE descriptions and units can now be stored for each value change.
• NGA command elements no longer store last values by default, reducing unnecessary storage overhead.
• The database-specific entries "backend.storeCommentsPerValue" and "backend.storeUnitsPerValue" now support dynamic data types. You can now also query for comments containing NULL or empty strings (e.g. WHERE _COMMENT=NULL).

CTRL

• Refactored the sendMail() function with improved error messages and additional parameters.

UI

• The License Management panel has been improved with new capabilities.
• Various DP Groups Check panel functions have been enhanced.
• A search button for filtering and double click navigation was added in the Console's Manager Properties panel.

Platform & Infrastructure

• The Qt version has been upgraded to 6.8.6
• The included Node-RED version has been updated to 4.1.5.
• The included PM2 version has been updated to 6.0.14.
• The vimacc version has been updated to 2.2.14.12.
• The API for the WinCC OA JavaScript Manager for Node.js was updated to version 2.3.10.

Northbound Manager: Distributed System Support

The Northbound Manager now supports Distributed systems for the Plantmodel (CNS) data source. Data from remote WinCC OA systems can be published through the Northbound Interface using the Plantmodel data source. The option Incl. system name in metric name allows you to prefix metric names with the source system name to distinguish datapoints from different systems.

SNMP

The config entry [snmpdrv] enableTraps now supports numeric values to control which trap versions are accepted. The legacy string values "Yes" and "No" remain supported for backward compatibility.

Northbound Manager: Quality Mapping

The Northbound Manager now supports quality mapping for Sparkplug B data publishing. The WinCC OA _invalid attribute is mapped to the Sparkplug B quality property, propagating data validity information to Sparkplug B consumers. Quality mapping can be enabled per data source using the "usequalitymapping" configuration option. See Quality Mapping.

UI

The function fillSvgElement() can now also be used for push buttons in the Qt UI.

GEDI

The Search Window now provides a new option to limit the search to open files only. Additionally, a "Case Sensitive" option has been added.

OPC UA

The OPC UA Server now supports Views as well as Dynamic Alarm Texts.

Drivers

• Support for the new OCPP driver has been added.
• DNP3 Driver: File Transfer is now supported.

SQL Queries

When querying data points, specifying only a data point name (without a root data point element) will now automatically include all sub-elements.