Which LED's to buy

Hello
I want to add led strip lighting to my enclosure for my printer. Which led’s is everybody using. Can you connect it to the printer’s power supply? I have raspberry PI 4 can I connect it to it?
Any help would be appreciated.

It depends on what you want from the LEDs. If it’s just general lighting, I went with:

Which, can be cut to the required length. When you take it out of it’s silcon casing, the LED strip fits inside the channels of the extruded aluminum frame of most printers and won’t be hit by the carriage wheels. I ended up buying 5m of the stuff but then decided not to do the entire printer frame, so 1m would actually have done. If I had to do it again, I would buy Cool White instead of Warm White.

If you have a non-stock motherboard, it may have a slot for Neo-Pixels. I’m not quite sure what they do with it, mind you. It could potentially be used for status lights or just a colourful display.

I’ve been buying it from Adafruit because Adafruit has a long history of supporting the maker community by writing libraries for a wide variety of controllers which they make available open-source and free-of-charge even if you aren’t buying Adafruit products.

The LEDs run (generally) at 12V. If you have a 12V printer, you’re good to go. If it’s a 24V printer, you can either put two strips wired in series or a dropping resistor in series. I went with a resistor.

As for your last question, it depends on what “it” is in the phrase “can I connect it to it?”. The first “it” probably refers to the Pi4 but are you asking if the Pi4 can be connected to the printer (yes, via USB cable), or to the LED strip?

If it’s the LED strip, the Neo-Pixel strip, listed above, runs at 5V and would work IF the strip is not too long. Each Neo-Pixel can draw up to 60ma so it won’t take too many to exceed the Pi’s current ratings.
Mind you, the pixel strip can be powered by an external source (external to the PI, that is) and signalled by the PI. That’s basically how my Christmas lights run.

Remember what I said about Adafruit deserving support because they’re helpful?

I kind of wish I’d found this a few years ago. Adafruit makes a comment that the signalling wire should have resistor in it to prevent the first NeoPixel from being destroyed by voltage spikes. I didn’t do that. Guess what happened to my first Christmas light?

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great information. We have some old deco style desk lamps that have ballasts and fluorescent tubes. My wife really likes hers but she wants me to convert it to LEDs so I’m interested in this sort of thing.

I have a combination of 1.0 meter long LED Strips with Aluminium housings attached to Work area.
These are 12VDC with a Wall wart style AC adaptor, I’m using a 2.5amp one with Breakouts for x2 strips. Purchased From NuTech Electronics On Parkdale Ave in Hamilton.
https://nutechelectronics.com/

Also I have 24VDC Bright white (4,200K i think) adhesive backed LED Strips on some of the printers themselves.

One Ender 3 Pro, the one with BLV Linear rail kit has a hard NeoPixel LED strip shortened to only 3x LED’s by the Nozzle

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If you go to convert one, just keep in mind that the ballast is likely in the base acting as a counter-weight as well as a means of lighting the tubes.

I’ll know when I have a look. I have a lot of heavy stuff I could put in there though.

So if l were to use led strip lights can l connect it to my printer power supply. I have raspberry pi 4 can I connect it there?

Again, pronouns… “…connect it there?” You were referring to your printers’ power supply in the previous sentence. If “there” refers to the power supply, definitely not. The power supply for most printers supplies 24 Volts whereas the PI runs on 5 Volt, so you’d kill the Pi instantly. On the other hand if there refers to the printer itself, yes you can connect the Pi to the USB port on the printer.

The only caveat I can think of is that the Pi4 can be a bit of a power hog. I just verified that my Pi4 will run off a USB2.0 port, although the little lightning bolt in the top-right corner of the screen indicates it’s feeling power-deprived. Mind you, I have the Pi display unplugged and I was using the HDMI port for video, so the Pi did not have to supply power for the screen. If you’re planning on running Octoprint with a backlit touchscreen, that might put it over the edge. I think I’d advise using the power supply that came with the PI to power it or get a 24V to 5V USB-C adapter if you want everything to run from the printer’s power supply.

As for the strip lights, yes, you can connect them to the printer’s power supply under one of the following three conditions:

  1. You buy a 24V LED strip light
    or
  2. You put 2 12V strip lights in series
    or
  3. You put a dropping resistor in series (that’s what I did)
    or
  4. If using a 5V LED strip (NeoPixel, for example), you plug it into a compatible controller board, if that’s what you’re using, or you plug it into the printer’s USB port, or you buy a 24V to 5V converter, or you use a larger dropping resistor.