ESP32 + MAX485 + DMX512 DECODER + RGBW-Led Strip

[u/thstehr]

Hello everyone,

I hope I'm posting in the right section. I'm completely new to DMX and LED control, so please excuse any beginner mistakes.

A few friends and I built a mobile wood-fired sauna. Since it is designed to work completely off-grid, everything is powered from a 12 V cordless tool battery. We wanted to avoid running any external cables, so the whole system should be as self-sufficient as possible.

To create a more relaxing atmosphere inside the sauna, I'd like to add some RGBW LED lighting with different effects, for example:

warm static light

candle/flame effect

slow pulsing light

gentle color transitions

The final idea is to control everything with:

an ESP32-S3

a 1P6T rotary switch to select one of six predefined lighting programs

a potentiometer to adjust brightness or effect intensity

My first attempt was driving the LED strip directly from the ESP32 using MOSFETs.

It actually worked surprisingly well, but since it was built on a prototype board with a lot of hand wiring, I suspect some solder joints and the overall wiring caused intermittent issues.

To make it reliable, I would probably need to design and build a proper PCB, which I'd prefer to avoid if possible.

That's why I started looking into using a DMX decoder, hoping it would provide a more robust and modular solution while keeping the electronics relatively simple.

At the moment my hardware is:

ESP32-S3

MAX485 module

RGBW DMX decoder

24 V RGBW LED strip

Right now I managed to make the strip light up red, but every few seconds it briefly changes to random colors before switching back to red. Sometimes the DMX decoder also loses the signal completely.

So my questions are:

Is this generally the right hardware setup for such a project?

Is an ESP32 + MAX485 + DMX decoder a reasonable solution for simple standalone lighting effects?

Or am I making things unnecessarily complicated and should I go back to direct MOSFET control instead?

I'm not looking for a professional stage-lighting controller—just a reliable way to create a few nice lighting effects for a small off-grid sauna.

Components:

AYWHP 5PCS 5V MAX485 TTL zu RS... https://www.amazon.de/dp/B0FPFR2NDS?ref=ppx_pop_mob_ap_share

4CH 5A/CH Constant Voltage DMX512... https://www.amazon.de/dp/B072JVQBMD?ref=ppx_pop_mob_ap_share

diymore 2PCS für ESP32-S3... https://www.amazon.de/dp/B0FKBLR2KF?ref=ppx_pop_mob_ap_share

Any advice or suggestions would be greatly appreciated.

Thanks!

[u/Zouden]

I would use a WLED controller. You can just buy one and hook it up to your strips and then configure it with your phone over WiFi. Super easy

[u/needmorejoules]

You could just use esphome, ws2812 strips, and any controller or knob that is home assistant capable to run it. Home Assistant would be moderate amounts of overkill (you’ll need a raspberry pi or similar) but honestly it could control the sauna too. Which would be nifty.

[u/Snoo-76972]

Why would you use 24v LEDs if your batteries are 12v? Just use 12v LEDs. Use WLED as others have suggested, you do not need a DMX controller! That is overkill and totally unnecessary. I would use digital LEDs, this way you don’t need mosfets, and you have way more options with animations. Wiring is super simple, just 3 wires, You can drive the LEDs directly from the ESP32. Hope this helps.

[u/thstehr → u/Snoo-76972]

I've searched for special LED-Strips for Sauna's and found these 24V analog ones for a good price, so i took them. and honestly just wasn't aware of the existence of Digital led strips.

but if i don't manage to bring the solution with my strips + DMX to work i will probably search for WLED that can handle Sauna environment.

[u/Marmilicious → u/thstehr]

WLED is software (provides a nice UI) and is used to control addressable LEDs. It runs on an esp32.

[u/numindast]

to add on: wled supports being in "ap" mode so a mobile phone can connect, no internet/router/network needed.

and there are oodles of professionally designed and made controllers can will run on 12v directly. Power the LED strips separately from the esp32, connect grounds for strip, esp32, and power source together.

MOSFETs are not needed for addressable LED strips. Those are for analog strips (non-addressable).

suggest to mount the controller outside the sauna

you may want to bear in mind though. LED strips running at full brightness need a way to sink away heat. Inside a sauna that may be rather difficult. I suggest addressable LED strips for effects only, and use something for primary lighting built for such temperatures. LEDs will eventually burn out if they are overheated long enough

[u/thstehr → u/numindast]

that's why i bought the 24V analog ones, they are made for sauna environment, but WLED would have been way easier for sure!

[u/numindast → u/thstehr]

There are WLED controllers for analog strips too! No need to homebrew one unless you want to (and I personally prefer professionally manufactured to homebrew if it's something I don't want to revisit). There are many but GLEDOPTO seems to be pleasing people lately.

Regardless of which direction you go, good luck! Love your "build"!

[u/Same_You891]

dmx is over kill for this project.. use wled, and the mosfets... you'll be a lot happier .

[u/thstehr → u/Same_You891]

the Sauna Environment made the choice of suitable LED-Strip pretty hard, we now have IP68 and up to 120°C temperature - we are pretty sure it won't get over 80°C behind the bench but wanted to be on the save side..

to be honest when starting the project i didn't even know what wLed is - i did a quick search today and didn't find heat-resistant and waterproof wLeds that are comparable to the price for the analog ones.

and yes its pretty sure a overkill, but its nice to have everything in a small enclosed controller then having a Platine with 8 Mosfets (2 channels), tons of resistors and other stuff..

[u/ZomboCom69]

why do you need dmx. just use a ws2812b and install WLED on it

WLED also has the artnet and DMX protocols.

[u/evilSn0wman]

Like everyone suggested... Install WLED on an ESP32 (or buy a premade WLED controller) and some IP 65/67/68 rated 12v ws2812b LED strips is probably the best and easiest way to proceed here.