About the Node-RED category


Node-RED is an open-source software development environment that lets you wire together devices, databases, cloud applications, and APIs (application program interfaces) with simple logic flows. It’s a visual tool often used for Internet of Things (IoT) and Industrial Internet of Things (IIoT) applications. Node-RED software and the two SNAP PAC controller Node-RED nodes are built into the GROOV-AR1 groov Box, making it easier to build mobile operator interfaces for monitoring and controlling IoT and IIoT data.

This category is for sharing flows, hints, tips, and projects with Node-RED.



My first post to this site so here goes.

For the past few days I have delved into Node-Red and have generated a Windows based dashboard of a mock up using my PAC. Things tried include Digital out read and display the state (red and green lights), read and chart (line graph and gauge) an element from a float table, and lastly setup udp input to view streaming data from the PAC - one point only as I am not sure how to progress further with other non-contiguous tags as well as including float table elements.

I have come across some issues that are not obvious as to how best address (maybe because I am not familiar with Java).

  1. How and where to get icons that may be used to develop the dashboard. For the material design icons, I managed to import and use them(albeit geared towards web/IT uses), but for icons from other sources, the path forward is not clear.
  2. Most probably due to the UDP listener (input), I have come across the “WARNING: Possible EventEmitter memory leak detected”. Not clear as to how to stop this from occurring.
  3. For the charts, “Warn {CHART NAME} More than two hundred points detected” This incremented by two hundred point at a time (200, 400, 600 etc) and having not followed this fully, it did appear that JAVA fell into a heap due to memory issues, closing down the Node-Red server. For the record, the time range was one hour at 5 sec intervals.

I am interested if anyone has come across these issues, and what/how was the fix or work around to prevent these from occurring and potentially crashing Node-Red.




Quick question. What platform are you running Node-RED on?

  1. I have been using groov as my UI, not the Node-RED dashboard, so have limited experience with those Nodes.
  2. What version of NodeJS are you running? I think this error occurred with an older version. (Should be 4.5 or better).
  3. Might be linked to issue 2?


Hi Ben,

Platform setup from two sources - PC and Node-RED
From Desktop computer
Running Windows 7 Enterprise - 64 bit

From Node-RED
Node-RED version v0.15.2
Node.js version v 6.9.1
Windows_NT 6.1.7601 x64 LE
Dashboard version 2.1.0

As you can see, I have installed the latest versions (about one month ago) so not sure what to look for. Any tips you can provide would be great.




Thanks for the versions, I am not sure how npm is bundled with node.js on Windows, so that version number does not mean much to me. (I have been using it on Linux).

Regarding the UDP stream from the PAC, can you switch to using the PAC nodes?

This would probably solve a few problems and give you some options going forward.


Is there ever going to be Node-Red for Groov-AT1 box


We had to draw the line somewhere, and sadly, the AT1 is on the other side.
Sorry about that.


This just gives me an excuse to buy the latest and greatest model, I assume that I can use the archive feature to move my Groov-AT1 over to a new Groov-AR1


That will both work and be the best way to move the project across.
(The new Node-RED in groov Admin is very cool and about to get very very cool with the next release of groov and some updated Nodes, so yeah, upgrading will totally be worth it).