# Replacing Thunder Nova Controller with RCD8445S(EC) Issues Connecting to Lightburn **URL:** \ **Category:** Ruida controllers\ **Tags:** rotary, update, firmware\ **Created:** [November 15, 2025, 2:47pm UTC](https://forum.lightburnsoftware.com/t/replacing-thunder-nova-controller-with-rcd8445s-ec-issues-connecting-to-lightburn/184980 "2025-11-15T14:47:48Z")\ **Posts on this page:** 1\ **Showing post:** 5
**Author:** ![ednisley](https://forum.lightburnsoftware.com/user_avatar/forum.lightburnsoftware.com/ednisley/32/40455_2.png) [@ednisley](https://forum.lightburnsoftware.com/u/ednisley)\ **Post date:** [November 15, 2025, 11:48pm UTC](https://forum.lightburnsoftware.com/t/replacing-thunder-nova-controller-with-rcd8445s-ec-issues-connecting-to-lightburn/184980/5 "2025-11-15T23:48:26Z")
> [@cjbrucks](#): > > “communication error” message even though it shows my file name on it Which is why we discourage using USB. ☹ > [@cjbrucks](#): > > any “hidden” item in Lightburn If you’ve gone through [the `Ruida networking` process](https://docs.lightburnsoftware.com/2.0/Guides/RuidaEthernet/#networking) _and_ picked an IP address for the laser that is not assigned to another device, then It Should Just Work. Presuming, of course, that the teeny Ethernet cable from the controller to the machine’s panel isn’t junk, which Is, alas, sometimes not the case, so try plugging the network cable directly into the controller. The machine display should then show the “network connected” icon in the lower right corner, LED12 on the back of the controller should be **on** to indicate the link is active, and LED11 should be blinking merrily to indicate network activity. Some previous discussions cover subtle network problems due to the network router assigning another device to the laser’s address and how to `ping` the laser to verify it’s where you think it is: > [@Random Letters Missing During Laser Cut – Only Works Fine One Letter at a Time](https://forum.lightburnsoftware.com/t/random-letters-missing-during-laser-cut-only-works-fine-one-letter-at-a-time/176022/): > > Hi everyone, I’m having a strange issue with my laser cutter and I’d love some help figuring it out. As you can see in the picture (from top to bottom, it shows my first to most recent attempts), some letters are randomly missing or partially cut when engraving text. I’m cutting at speed 50mm/s and power 35%. I’ve already tried applying an offset, and then used the Pathfinder tool (unite/merge) afterward — but there’s always a small issue somewhere. What’s odd is that if I cut each letter in… > [@Laser stops running after a few seconds](https://forum.lightburnsoftware.com/t/laser-stops-running-after-a-few-seconds/176474): > > Hello. I’m new to the forum but have been using my OMTech 70W Co2 laser for a couple years. I’m wondering if anyone else has had an issue with the laser stopping after a few seconds. I was running a batch of stuff and as soon as I changed files, Lightburn said it needed to be updated (to version 2.0.02). I did the update and that was it. Every time I try to engrave, it stops after a few seconds. Nothing else changed except for the update. I’ve reinstalled old versions, rebooted everything, and n… > [@Laser jumps and does not cut the image on the cut line](https://forum.lightburnsoftware.com/t/laser-jumps-and-does-not-cut-the-image-on-the-cut-line/175514): > > I am operating macOS Sequoia 15.5 on Apple M1 system. After installing v2.0.00 and trying to cut the laser will jump and cut a line that does not exist on the workspace? I tried multiple times to cut different images and the same occurs each time. I did the update and the same issue. I have reverted back to 1.7.08 and no issues. Any suggestions would be appreciated, --- _[View the full topic](https://forum.lightburnsoftware.com/t/replacing-thunder-nova-controller-with-rcd8445s-ec-issues-connecting-to-lightburn/184980)._