Home
Web Connectivity / Network Interfaces
Data exchange, APIs and web technologies
APIs
An overview of the APIs (Application Programming Interface) available in WinCC OA.
OA RxJS API
The OA RxJS API is a reactive JavaScript/TypeScript library for real-time communication between web applications and WinCC OA.

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.
Web Connectivity / Network Interfaces
Data exchange, APIs and web technologies
- APIs
  An overview of the APIs (Application Programming Interface) available in WinCC OA.
  - API Manager
    The WinCC OA API (Application Programming Interface) offers a number of functions adding special Managers to this process control system.
  - oaJsApi
  - OA RxJS API
    The OA RxJS API is a reactive JavaScript/TypeScript library for real-time communication between web applications and WinCC OA.
    - oa-rx-js-api
  - WinCC OA Manager API for Node.js
    The WinCC OA Manager API is a Node.js AddOn that enables you to develop custom managers in JavaScript or TypeScript.
  - NGA Backend API
  - Manager Service API (MSA) – High-Level Overview
    The Manager Service API (MSA) is the backbone for seamless, protocol-independent communication and logic reuse between WinCC OA managers, supporting modern distributed and web-integrated SCADA architectures.
- Manager Service API (MSA) – High-Level Overview
  The Manager Service API (MSA) is the backbone for seamless, protocol-independent communication and logic reuse between WinCC OA managers, supporting modern distributed and web-integrated SCADA architectures.
- COM
  COM - Microsoft Interface stands for Component Object Model, a specification for developing modular software components which can be used by each COM compatible application. COM components can be easily integrated in such applications and can even be removed from an application at run time. COM components can be programmed in various different programming languages although C++ is used mostly. The specifications OLE, ActiveX and DirectX are based on the COM technology.
- Prometheus Interface
  The Prometheus interface (also referred to as Prometheus client) serves as a bridge between WinCC OA and Prometheus. It facilitates the retrieval, processing, and exposure of data from the WinCC OA system to a Prometheus-compatible format. This allows Prometheus to monitor and alert based on the data fetched from the WinCC OA system.
- SIMATIC PLC Discovery
  In increasingly dynamic automation environments and the merging of IT with OT, the SIMATIC PLC Discovery can help with the connection of newly added S7/S7+ devices by showing you all the devices in the network
- WinCC OA JavaScript Manager for Node.js
  The WinCC OA JavaScript Manager for Node.js is a manager that allows for the integration of the TypeScript/JavaScript runtime environment Node.js into WinCC OA.
- SIMATIC Unified AR (Augmented Reality)
  SIMATIC Unified AR is an industrial Augmented Reality app that allows to display and operate HMI screens (WinCC Unified / WinCC V8) and web applications (WinCC OA Dashboard) in real production environments.
- webserver.js
  webserver.js is a Node.js-based web server that provides a modern, extensible backend for full-stack web applications in WinCC OA.
- HTTP Server
  The HTTP Server integrates Internet technologies directly into WinCC OA . Implemented as an add-on for the Control Manager, possible applications are many and diverse. The HTTP Server can be used as a web server for static HTML pages including download facility or to generate dynamic HTML pages.
- XML-RPC
  XML-RPC (Extensible Markup Language Remote Procedure Call) allows software on different operating systems to make procedure calls over the internet. XML-RPC uses HTTP for the transport and XML for the encoding. It sends the procedure call to a remote server through HTTP. The call is an XML document and it receives the response as XML.
- REST Reporting API
  The REST Reporting API is integrated into the Standard web server and can be activated via the config entry [restRporting] enabled.
- Distributed systems
  Distributed systems in WinCC OA allow to connect two or more autonomous WinCC OA systems via a network.
- Dist-Management
  Configuring and maintaining a distributed system in WinCC OA requires a high amount of engineering effort due to a high number of settings and configuration steps that must be applied on several systems. The Dist-Management reduces the engineering effort and simplifies the necessary settings.
- XMPP
  XMPP (formerly Jabber) is mostly used in chat (instant messaging) applications and allows near real time communication between two or more parties. It can, e.g., be used to push information from a WinCC_OA project server to one or more persons, even allowing the recipient to send a confirmation back to the server.
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.
eLearning
Build Your Expertise Step by Step
Documentation
Basic information about terms and functions within the documentation.
Support & Services
An experienced team of support agents, consultants and trainers are ready to facilitate active partnerships with our customers, so they can profit from our comprehensive service.
Disclaimer
A brief clarification of liability exclusions or legal notices.

OA RxJS API

The OA RxJS API is a reactive JavaScript/TypeScript library for real-time communication between web applications and WinCC OA.

The OA RxJS API (@etm-professional-control/oa-rx-js-api) provides a WebSocket-based interface that enables web applications to interact with the WinCC OA runtime. Built on the RxJS reactive programming framework, it delivers real-time data streams and event-driven communication for custom web frontends.

Key capabilities

Connect to datapoints in real time using dpConnect and reactive observables
Read and write datapoint values (dpGet, dpSet)
Execute datapoint queries (dpQuery, dpNames)
Subscribe to system events (datapoint creation, deletion, type changes)
Retrieve historical and alarm data (dpGetPeriod, alertGetPeriod)
Authenticate via JSON Web Tokens (JWT)

Use cases

Use the OA RxJS API when building custom web-based dashboards, monitoring applications, or operator interfaces that require live data from WinCC OA. The API is also the foundation of the Widget Development Kit (WDK).