Home
Northbound Interfaces
Your portal to the cloud or supervising systems.
OPC HDA
OPC HDA Client
The WinCC OA OPC (OLE for Process Control) HDA client allows to query, display and save historical data from OPC HDA servers.

Version Information
Release Notes, Update information, Certifications and Frequently Asked Questions.
Concepts
Your first step into modern and powerful process visualization.
Deployment
Topics, you need to know, before using WinCC OA.
Security
Go beyond the norm in cybersecurity.
Engineering
Powerful tools for easy or complex engineering tasks.
Data Management
Classify, structure and archive your data.
Business Logic / Control
Endless possibilities in data processing for your projects.
Data Visualization
User interfaces, Trends and Reports for every purpose and device.
Southbound Interfaces
The process connection to the actual machines/sensors.
Northbound Interfaces
Your portal to the cloud or supervising systems.
- MQTT Publisher
  The MQTT publisher provides a northbound data interface for MQTT clients to data point values within the WinCC OA project.
- Node-RED
  Node-RED is a flow-based programming tool that allows the creation of applications in a graphic environment.
- OPC UA Server
  The WinCC OA OPC UA Server provides an OPC UA interface to access WinCC OA data point values, alarms and historical data.
- OPC Server
  The OPC Server enables the communication with OPC clients.
- OPC HDA
  - OPC HDA Server
    The WinCC OA OPC Historical Data Access (HDA) Server is used for the exchanging of archived process data of the WinCC OA project.
  - OPC HDA Client
    The WinCC OA OPC (OLE for Process Control) HDA client allows to query, display and save historical data from OPC HDA servers.
    - Requirements and installation
    - OPC HDA Client Configuration
    - DCOM settings for Remote Servers
    - Query historical data
    - [opchda]
      Settings for the OPC HDA client
    - Internal data points of the OPC HDA Client
    - OPC HDA Client - Redundancy
- OPC Alarms & Events
  OPC Alarms & Events (brief OPC A&E) is in addition to the Data Access another standard in order to implement a central alert management manufacturer spanning. OPC A&E is used to guarantee the coupling with other control systems as well as to display alerts and events in a hierarchical system
- Modbus/TCP Server
  The Modbus/TCP server provides the possibility for Modbus/TCP clients to query data from a WinCC OA system and arrange the data within a Modbus data model.
- SNMP
  SNMP (Simple Network Management Protocol) is a protocol for monitoring network devices (servers, workstations, routers, switches and hubs etc.) and their functions. It allows you to administer your network.
- OLE DB Provider
  OLE DB is a Microsoft specification for accessing data on different computers. It is based on Microsoft's COM technology and is the successor to the older and limited ODBC technology.
Web Connectivity / Network Interfaces
Data exchange, APIs and web technologies
User Management
All about authorization, authentication and login-customization.
Availability
How to get your system uptime to the maximum.
Reporting
Create state of the art project reports without limits.
Addons
Useful tools and enhancements for special demands.
Reference Tables
Detailed and extensive content for special project adaptation.
Videos & Tutorials
Explore the capabilities of WinCC OA with our carefully selected collection of video tutorials and guides.
WinCC OA Documentation
Basic information about terms and functions within the documentation.
Disclaimer
A brief clarification of liability exclusions or legal notices.

OPC HDA Client

The WinCC OA OPC (OLE for Process Control) HDA client allows to query, display and save historical data from OPC HDA servers.

Notes and restrictions

The OPC HDA client is only supported for Windows.
The OPC HDA client supports the OPC HDA specification version 1.20
The OPC HDA client supports simultaneous connections with up to 32 OPC HDA servers
The OPC HDA client only supports working with 64Bit OPC HDA servers
Following OPC HDA data types are supported
- VT_BOOL
- VT_I4
- VT_UI4
- VT_R8
- VT_UI4
- VT_DATE

The debug flag -dbg 10 provides information if the server list is changed, the connection to a server is lost or a state/browse request is performed.
Following of the OPC HDA specification is not supported:
- Aggregate functions
- asynchronous functionality
- update functionality