Node-RED is a tool for wiring together hardware devices, APIs and online services in new and interesting ways. Using NodeRED the emonPi can become a central hub for home automation, control and notification.

At the heart of Node-RED is a visual editor allowing complex data flows to be wired together with little coding.

Node-RED is NOT pre-installed on emonSD-30Oct18, see NodeRED RaspberryPi Install Guide to install

Node-RED is pre-installed on emonSD pre 2018, see emonSD repository and change log. If you are running an emonSD image that includes Node-RED just browse to:


Username: "emonpi"
Password: "emonpi2016"

Or substitute emonpi for your local emonpi’s IP address if hostname lookup does not work

default node red

The Node-RED visual editor should load in the web browser with an example flow. The example flow subscribes to the emonPi MQTT (see MQTT docs) and extracts real-time values.

Make changes to the Node-RED flow by dragging-and-dropping nodes and connecting flows. Hit deploy to save and execute the configuration.

On the emonPi the node-RED data folder /home/pi/.node-red is soft-linked to the read-write folder /home/pi/data/node-red so modifications to the flows can be saved.

For inspiration on what can be achieved with nodeRED and MQTT check out Martin Harizanov’s IoT Google hangout.


emonPi Node-RED