Node-RED

Node-RED is a flow-based programming tool that allows the creation of applications in a graphic environment.

What is Node-RED?

Flow-based programming breaks an application down into a network of small black boxes (in Node-RED the eponymous nodes) with a fixed internal logic. The nodes have fixed connections to one another. Data is transmitted between the nodes in the form of messages.

Node-RED itself is part of the OpenJS Foundation. As such it is an open source program based on JavaScript and Node.js. This means that all programs created with it can easily be shared as JSON files.

All information and documentation of Node-RED can be found on the Node-RED website: nodered.org

Node-RED is focused on intuitive use, and can be used to set up applications without deeper programming knowledge.

Node-RED in WinCC OA

Node RED in combination with WinCC OA provides a graphic programming environment for applications, which is easy to set up and equally easy to use.

The WinCC OA Installation of Node-RED includes the specially developed WinCC OA Nodes, which enable construction of WinCC OA-specific programs. The tool for working with Node-RED in WinCC OA is the Node-RED Wizard.

Node-RED Components

To operate Node-RED in WinCC OA, a WebSocket Secure Server and an HTTPS server for Node-RED (this will be referred to as the "Node-RED server") are used. A Control Manager with both of these servers is created by the Node-RED Wizard during the Node-RED installation. The manager is started automatically with the "nodeRed.ctl" script and the Node-RED user set in the Node-RED Wizard. You can also use more than one WSS Server. The servers will then have to be assigned to the nodes in the Node-RED Editor.

Remember: A separate HTTP server license is needed to start the WebSocket Secure Server.
Figure 1. Server Setup Node-RED

The WebSocket Secure server is started in a Control Manager. It communicates with the WinCC OA nodes on the Node-RED server, which itself is a runtime application of Node.js. Inside Node-RED the HTTPS Node-RED server communicates with the browser, placed in the Node-RED Wizard, to provide visualization of the graphic interface.

Node-RED Wizard

You can find the Node-RED Wizard in the GEDI, in the "tools" section. Use the wizard to install, configure, change and work with Node-RED.

Wizard Page Description
Editor Provides the central Node-RED Workspace including the WinCC OA Nodes and the Example Flows
Admin Used to set up Installation of Node-RED
Security Includes the Security Settings as well as Basic Settings and access to the Node-RED User-Management
Overview Provides a Status Overview of Servers and Flows as well as the Debug Log

Disclaimer

Please note that Node.js, Node-RED or the node packages used in our examples have been thoroughly tested and checked using effective control measures.

However, we expressly exclude a guarantee for those software products. Our installer panel makes those software products available "as are".

Installing additional node packages via the Node-RED palette option remains possible but the entire risk that arises from the usage of those packages remains with the user.