Automatically push production counts and material consumption from WinCC directly to SAP or Microsoft Dynamics at the end of a shift, eliminating manual data entry errors.
: Using the REST Connector to push data to IoT hubs or AWS/Azure endpoints.
to bridge the gap between industrial automation (OT) and IT systems. It allows external applications—like ERPs, MES, or mobile apps—to read and write SCADA data using standard web protocols like HTTP/HTTPS and JSON. www.siemens.com Two-Way Communication in WinCC V8
| Problem | Likely Cause | Solution | |---------|--------------|----------| | 401 Unauthorized | Wrong user/password or missing role | Assign "REST API access" role in WinCC User Administrator. | | 404 Not Found | Wrong endpoint or API version | Check /swagger endpoint; use /api/v1/... as base. | | 403 Forbidden | User lacks tag read/write permission | Grant tag-specific permissions in WinCC. | | Connection refused | REST API not enabled or wrong port | Verify runtime settings and firewall rules. | | Slow response | Large tag list or high-frequency polling | Use bulk read endpoints; reduce polling rate. | wincc rest api
"name": "Temperature_Sensor_1", "value": 24.7, "quality": "Good", "timestamp": "2026-06-01T10:30:00Z" Use code with caution. Practical Code Example: Python Integration
Training machine learning models for predictive maintenance.
The WinCC REST API transforms WinCC from a traditional standalone industrial monitor into an agile, IT-friendly data engine. By standardizing industrial communication into web-friendly HTTP and JSON requests, it empowers developers and engineers to build a smarter, more interconnected enterprise. Whether you are looking to build simple custom reports or feed complex machine learning pipelines, mastering the WinCC REST API is your key to unlocking the true potential of Industrial IoT. It allows external applications—like ERPs, MES, or mobile
This design choice is what makes the REST API so transformative for SCADA integration. Traditional OPC DA, while powerful, requires complex DCOM (Distributed Component Object Model) configuration, making it difficult to use outside a single local network. The REST API, on the other hand, can be accessed from virtually any device that can make an HTTP request, be it a cloud platform, an MES (Manufacturing Execution System) database, a custom web dashboard, or a mobile app. As a result, it has become a key enabler for industrial digitalization, fostering seamless collaboration between OT and IT teams.
| Endpoint | Method | Description | |----------|--------|-------------| | /auth/login | POST | Authenticate user, receive session token. | | /auth/logout | POST | Invalidate session. | | /tags | GET | List all tags (names, types). | | /tags/<tag_name>/value | GET | Read value of one tag. | | /tags/<tag_name>/value | PUT | Write value to one tag. | | /tags/values | POST | Read multiple tags in one request. | | /tags/values | PUT | Write multiple tags. | | /alarms/current | GET | Get active alarms. | | /alarms/archive | GET | Get historical alarms (with filters). | | /users/current | GET | Get logged-in user info. |
The server responds with a JSON payload containing an access token (e.g., a JSON Web Token). This token must be included in the header of all subsequent requests: Authorization: Bearer . Step 3: Reading a Tag Value Once authenticated, you can query a specific process tag. as base
API access is bound to the WinCC User Management system. You can create specific API users with restricted "Read Only" access to prevent external systems from accidentally changing critical machine setpoints.
For long-term analysis, the REST API allows you to extract historical tag logs. This data can be fed into external databases, data lakes, or Business Intelligence (BI) tools. 4. Integration with IT Platforms
WinCC V8.0 features two distinct components for REST-based integration: WinCC/REST API (Inbound):