Wincc Rest: Api

| Feature | Description | Method Example | | :--- | :--- | :--- | | | Fetch current value of a single or multiple data points (datapoints). | GET /api/dp/$dpName | | Write Tag Value | Send a command to change a setpoint or control a valve. | PUT /api/dp/$dpName (Body: "value": 50 ) | | Get Alarm List | Retrieve active or archived alarms/events. | GET /api/alerts/active | | Acknowledge Alarm | Confirm an alarm from a remote dashboard. | POST /api/alert/$alertId/acknowledge | | Query Archive Data | Retrieve historical trends for a time range. | GET /api/history/$dpName?start=...&end=... | | User Authentication | Log in/out, check permissions. | POST /api/auth/login | | Browse Data Points | Discover the tag structure dynamically. | GET /api/dp/browse?path=System1. |

In this post, we’ll dive deep into:

The SIMATIC WinCC V8.0 REST API is a modern interface that enables external applications to access configuration and runtime data from the SCADA system using standard HTTP methods and JSON. wincc rest api

All traffic must be encrypted to prevent eavesdropping and man-in-the-middle attacks.

Industrial tags include a "Quality Code". Always check this code in your code. If the quality is "Bad" (e.g., due to a disconnected sensor), your IT application should ignore the data or flag an error. | Feature | Description | Method Example |

Note: A quality code of 128 (0x80) traditionally signifies a "Good" DAQ status in WinCC systems. 2. Writing Runtime Tags

Unlike classic OPC or proprietary Siemens protocols (like S7 communication), the REST API uses JSON payloads, making it language-agnostic and cloud-friendly. This bridges the gap between industrial automation and enterprise IT systems. | GET /api/alerts/active | | Acknowledge Alarm |

import requests

The service typically runs as a self-hosted web application, often leveraging Microsoft’s OWIN (Open Web Interface for .NET) framework, listening on a specific TCP port (default often 443 or a custom high-port) for HTTPS requests.