Using a browser or Postman, navigate to:
http://<Your_IP>/WinCC/REST/version
If successful, you receive a JSON response like:
"Version": "17.0", "APIVersion": "1.2"
TestInt every 5 seconds and prints changes.Within an hour, you’ll have a working integration.
The WinCC REST API bridges the classic SCADA world with modern web and cloud ecosystems. It’s not the right tool for every job (stay away from high-speed control loops), but for dashboards, reporting, ERP integration, and remote monitoring, it’s a game-changer.
Your next steps:
The era of locked-in SCADA data is ending. With REST APIs, your WinCC system becomes a first-class citizen in the connected enterprise.
Have you implemented WinCC REST API in a real project? What challenges did you face? Share your experience in the comments below!
WinCC REST API is a self-hosted service available in WinCC Runtime Professional
that allows external applications to interact with SCADA data using standard HTTP methods and JSON. It serves as a modern bridge between industrial OT (Operational Technology) and IT environments, enabling AI agents, web dashboards, or custom applications to read and write tag values and configuration data. 1. Key Capabilities Data Access : Read and write both Runtime data (live tag values) and Configuration data (project setup). Standardized Methods wincc rest api
: Uses common HTTP methods (GET, POST, etc.) and JSON payloads, making it compatible with languages like Python, JavaScript, and C#. : Supports secure communication via
and flexible authentication mechanisms to protect sensitive industrial data. Self-Hosted Service
: The REST service monitors a configured URL and port using the Microsoft C++ SDK. 2. Implementation Guide
To integrate the WinCC REST API into your workflow, follow these general steps: Configuration in WinCC Enable the REST service within the WinCC project settings.
Define the specific port and URL that the service will monitor. Ensure the WinCC Runtime is active, as the API interacts with the running process. Authentication & Connectivity
Set up a secure connection (e.g., VPN or encrypted tunnel) for IT/OT integration.
Configure HTTPS to ensure data integrity during transmission. External Interaction Use tools like (libraries such as ) to send HTTP requests to the WinCC endpoint. Write a small Python script that reads TestInt
: Perform a GET request to query specific tag values for real-time monitoring. Write Tags
: Perform a POST or PUT request to update tag values from external logic (e.g., an AI optimization command). 3. Common Use Cases AI & Machine Learning : Feeding live data into Python-based models for predictive maintenance or anomaly detection. Custom Dashboards
: Creating web-based visualizations that display SCADA data alongside other business metrics. Middleware Integration
: Using edge devices to preprocess data before sending it to cloud platforms or AI agents to reduce latency.
For detailed technical specifications and API endpoint documentation, refer to the Siemens Industry Online Support (SIOS) portal WinCC RT Professional documentation sample Python script to demonstrate how to read a tag value using this API?
The WinCC REST API is a modern interface introduced in WinCC V8.0 WinCC Unified
that enables external applications to exchange data with the SCADA system using standard web protocols. It allows for both pulling data from WinCC (Server mode) and pushing data to external services (Connector mode). Key Capabilities Data Access Within an hour, you’ll have a working integration
: Read and write WinCC configuration data, runtime tag values, and archive tags using standard HTTP methods like Messaging System
: Access and filter message system data (alarms) via the REST interface. Bidirectional Communication WinCC REST Service : Acts as a server, allowing external tools like or custom web apps to query WinCC. WinCC REST Connector
: Acts as a client, enabling WinCC to actively send runtime data or alarm texts to external REST interfaces or cloud platforms. Security & Authentication : Supports secure communication over
with flexible authentication mechanisms, including Basic Authentication. Configuration Steps
To set up the WinCC REST Service, follow these general steps: REST Reporting API - WinCC OA
urllib3.disable_warnings(urllib3.exceptions.InsecureRequestWarning)