A cheap & waterproof 12 amp WLED controller box

I built four new pixel controller boxes this spring, and they ran the FOH wall and all the environment strings at Spacetime @ Kosmos 2026. They're super clean, small, waterproof and easy to install - and the whole bill of materials is about 80€ per box.

The parts

Part	Link	Price
AliExpress IP hard case	Aliexpress	13€
Gledopto Elite 4D-EXMU controller	Aliexpress	25€
Meanwell XLG-150-12-A power supply	Digikey	28€
Ethercon feedthrough (Rean RRE8F-Z-000-1)	Thomann	5€
xConnect & power wires, rubber gaskets, wagos	Aliexpress	5€

Note: The links are not the best deals or affiliate links or anything such - they are just examples of which components I used in this project. You will likely find better deals by searching, as these links will get old and the prices will change.

Each box drives 4 outputs at 60 fps, 3 universes (or 510 LEDs) per output - the LEDs are plenty bright when the string gets power from both ends.

The 510 pixels per output describe the data configuration. Don't assume the 12 A supply can run all 4 × 510 RGB pixels at unrestricted full white. Work out the current draw for your pixels at the brightness limit you'll use. Size the wiring and connectors for that load, with suitable protection on each power branch. WLED's current limiter doesn't replace that protection.

The build

The build is super simple. Drill five eight millimeter holes in the box, one for the power, four for the xConnect pigtails. One larger hole for the Rean ethercon feedthrough. Screw in and glue the ethercon. Put the rubber gaskets in the drilled holes, stuff the pigtails through the gaskets, connect everything with wagos accordingly. Each pigtail gets 12v and ground from the power supply and data from WLED. If paranoid, seal sketchy parts with hot glue.

The WLED settings that matter

Once WLED is on the box there are five things that might be worth changing. The rest of the defaults are usually fine.

Give every box a static IP and label the box. This is the whole reason I moved to WLED in the first place - the addresses are mine to decide, not whatever the controller firmware feels like. Filament can find Art-Net nodes on the network and fill in the IP for you, but I still pin them by hand and label the boxes. I want box 4 to be box 4 at every gig, not whatever DHCP handed out during load-in while forty other things were being plugged in. Also, when the boxes have clear markings of their address, it's much easier to figure out which box is causing trouble when fumbling in the dark between the moltons on the stage.

Pick the right ethernet type. The ethernet port is the point of this build, and in WLED you have to tell it which board it's sitting on before that port does anything. Gledopto wleds have most of these pre-configured out of the box.

Art-Net, and count your universes. 510 LEDs on an output is 1530 channels, so that's three universes per output and twelve universes of pixels per box. At 60 fps, twelve universes means 720 packets a second leaving one box.

One numbering gotcha worth double-checking: Art-Net universes start at 0, sACN (E1.31) starts at 1. Filament and WLED both let you set the start universe, so just make sure they agree. An off-by-one there looks like a broken LED strip.

Four outputs, and the pinout is printed on the board. IO16, IO12, IO4 and IO2. Set each output to 510 and target FPS to 60.

Why 510 or 512

A DMX universe holds 512 channels, but an RGB pixel eats 3 of them. 512 ÷ 3 = 170.67, so if you fill the full 512, pixel #171 gets split across a universe boundary - its red channel lands at the end of one universe and green and blue at the start of the next. That's a recipe for color glitches and off-by-one headaches. 170 pixels × 3 channels = 510 fills the universe cleanly, and the last 2 channels just go unused.

So in WLED: 3 universes × 170 pixels = 510 LEDs per output. Make sure each output's start universe increments by 3 so nothing overlaps: outputs starting at universes 0, 3, 6 and 9.

The one exception is RGBW. Four channels per pixel divides 512 evenly (128 pixels × 4 = 512), so the math flips and full universes work fine there. For plain RGB seed pixels and regular WS2811/WS2812 strips, which is most people, most of the time, 510 it is.

Make it boot dark. Set the startup preset to plain black. WLED drops out of realtime mode a couple of seconds after the Art-Net stream stops and falls back to that preset, so losing the network means the artwork goes dark instead of a giant LED artwork deciding to show a full-brightness rainbow in the middle of somebody's set.

WS2811 Frame Rate vs. DMX Universes

The limiting factor is the WS2811 data transmission speed, 800 kbps. Each RGB pixel takes 30 µs to transmit, plus a ~300 µs latch time per frame.

A DMX universe holds 170 RGB pixels (510 DMX channels).

So the frame time is (Pixels × 30 µs) + 300 µs.

For 60 fps, a frame has to go out in 16.67 ms or less. Three universes (510 pixels) fit, four (680 pixels) don't.

Universes	Pixels	Frame Time	Max FPS
1	170	5.4 ms	~185 FPS
2	340	10.5 ms	~95 FPS
3	510	15.6 ms	~64 FPS
4	680	20.7 ms	~48 FPS
5	850	25.8 ms	~39 FPS
6	1020	30.9 ms	~32 FPS

So I limit each WS2811 output to 3 DMX universes (510 pixels) and get smooth 60 fps.

Other controllers

I have older, beefier controllers too - a 2U rack case with 12 fused XLR outs, 2 × 25 A Meanwells and a Club Lights 12 Pro from AliExpress, plus a couple of boxes with up to 16 A supplies and an H802RA for four outputs. Two of these rack versions ran the five crystals this year at Kosmos Festival and have done so for many other projects.

But the AliExpress boxes have fixed ideas about IP addresses, and when they lose data they just freeze. The WLEDs are completely flexible about their network config, and they can fail more gracefully by falling back to their own programs.

Connectors

xConnect, always. I love the large plugs. I've previously had many smaller and more fiddly connectors, but xConnect is stupid, simple and it works. I've stepped on these countless times and have yet to break one by accident. Sometimes there have been deformed plastic parts in orders, but it is still by far the best connector I've used for these. You might think the o-ring is not exactly required due to how tight they fit - don't fool yourself. It's essential for waterproofing, I've had strips freak out due to moisture in the connection, causing flickering and flashes of colors, making the problems very obvious.

We use seed pixels for many things. They are ip68, are easily glued into place and cheap. You can order them with the connectors so there's no soldering needed at all.

What's your setup like?

I'm very interested in how you have built your controllers! Come show your rig on our Discord.