Category: Nodes

In this tutorial we are going to look at using the node-red-contrib-bool-gate module which provides four basic boolean logic functions. If you are unfamiliar with logic gate operation the first section covers the logic gates and the second covers using the logic gates in node-red flows. Click to rate this post! [Total: 0 Average: 0]

Having things happen at a particular time, or in response to another event is a common requirement in node-red flows. Examples are: Turning on/off central heating at scheduled times. Turning on sprinkler system at a particular time. Turning on a conveyor belt after an item has been added. Sending an email in response to a fault. Click to rate this post! [Total: 0 Average: 0]

Shelly devices support both the http and the MQTT protocol and you can use either protocol to control and change the settings of Shelly devices. Just as with Tasmota devices you can use either the standard HTTP and MQTT nodes or alternatively install the Shelly nodes. Click to rate this post! [Total: 1 Average: 5]

An error in a node-red flow will generally cause an error message to be written to the debug sidebar. However in many cases it is important that you handle errors rather than just simply logging them. Node red provides the catch node for catching errors caused by nodes in the tab. Click to rate this post! [Total: 0 Average: 0]

Up until now node-red dashboards have all been based on the dashboards nodes in the node-red-dashboard module. This was a third party module and was based on a version of angular (V1) which is no longer maintained. The project is now deemed to be on Life support -see here Click to rate this post! [Total: 6 Average: 3.2]

With most programs functions are blocking in that they will complete their task before returning. Generally this type of programming is easy to manage as you have only one task active at any time. This style of programming is known as synchronous, but  the problem with it is that it can make applications very slow as they have to continually wait. Click to rate this post! [Total: 0 Average: 0]

Incoming MQTT data is often JSON formatted data and in order to extract data values from it. Storing the data directly as JSON formatted data is also common However it is also very common to store this data as CSV or a least convert it to CSV for use in legacy systems. Click to rate this post! [Total: 2 Average: 5]

Because node-red is a nodejs applications it is possible to use nodejs modules in node-red. Depending on the version of node-red that you are using there are two ways of doing this: Editing the settings File -All versions Setup tab in the function node -1.3 and above Click to rate this post! [Total: 2 Average: 5]

Influxdb is specially designed for time series data and as such it is a popular choice for storing sensor type data. Influxdb underwent a major change in version 2.0 and so you need to careful what version you are using. Click to rate this post! [Total: 1 Average: 5]