Node-RED is a user-friendly open-source software for programming PLC behaviour through the so-called flow-based method.
What is Node-RED?
Node-RED is an open-source web-based programming tool that utilizes the flow-based approach. This method is based on so-called nodes, with each node having its own specific function. Depending on its function, each node then processes input data and sends them to the next node in line. The application behaviour itself is then created by simply placing nodes and chain-linking them into flows. Aside from user-friendliness this approach also makes the resulting programs very clear and significantly simplifies troubleshooting.
Node-RED user interface screenshot
The Node-RED user interface is accessible via a regular web browser and features a large collection of nodes covering basic automation tasks (switching of inputs/outputs, reading data from sensors, notification sending etc.). Users also have the option to create custom nodes or to implement nodes created by community members. Complete flows can be then exported and shared as JSON files. Aside from these features the interface also allows you to design responsive web interfaces or communication with cloud services. vices.
Node-RED on Unipi controllers
Node-RED is compatible with all Unipi controllers. To make its installation as easy as possible, we offer a pre-assembled OS image Aside from pre-installed Node-RED and other necessary services and configurations the image also contains the EVOK - a set of web-based APIs used for programming in Node-RED.
Images are available for free on this link. Installation guides for all Unipi PLC product lines are then available on the following links:
- Node-RED on Unipi Axon installation guide
- Node-RED on Unipi Neuron installation guide
- Node-RED on Unipi 1.1/1.1 Lite installation guide
Node-RED support provided by Unipi
Aside from the OS image we provide partial technical support for Node-RED, covering preparations of Unipi hardware for the installation. Technical support for the software itself is not provided. If you encounter any issue with Node-RED, please consult the Node-RED community forum or visit the Node-RED section of the Unipi community forum.
Blog series: Starting with open source software
Check out our new series of articles in which Node-RED is used as an environment for showcasing the use of open source tools on Unipi PLCs.
- PLC programming (1): Starting with open source software
- PLC programming (2): Working with inputs/outputs
- PLC programming (3): Working with external peripherals using Modbus
- PLC programming (4): Integration of an indoor air quality sensor using MQTT
Case study - a practical example of using Node-RED
Node-RED is available as a pre-installed SW solution for Unipi Gate controllers designed for remote monitoring and management of existing technologies. The Sending temperatures from Unipi Gate to a ThingsBoard cloud case study demonstrates how to read temperatures from the Unipi xG18 8-channel 1-Wire extension module using the Unipi Gate, send the values to the ThingsBoard cloud platform via the Node-RED software and visualize them.