ESP32 reboots above certain brightness

I’ve built a 200 led panel, using 4 lengths of wired led buttons, an 8amp 5v PSU and a GOOUUU ESP-32.
I ran power to the ends and middle of the LEDS, and connected 5v, data and GND directly to the ESP-32. That’s it, no resistors or caps.

It all works well at low brightness, but resets the ESP-32 if set above a certain brightness. If I use the current limiter, I have to set it to 3000ma before the effects I have set up will run without resetting.

Theoretical 12000ma max draw, 8000ma PSU and yet I have to limit it to 3000ma to reliably work.
Any ideas please?

I’d suspect an out-of-spec power supply. Your 200 LEDs should pull 6.7A max.

Monitor the output voltage as you turn up the brightness.

No reputable PSU manufacturer would do this, yet I’ve seen it - presumably on less than reliable PSUs…

The stamped current rating is max peak current, with max sustained current printed in smaller letters, perhaps between ()s.

That should be the other way around, with say 3000mA sustained (8000mA peak) @ 5VDC.

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Thanks for your reply.
How do you get 6.7A?
I’ve always based calcs on 60ma per LED so 200*.06 = 12A.
WLED should limit to .55 so 11A max without software limiting.

It is a cheap Ali-express supply so out of spec is possible.
I will get the multimeter out tomorrow.
What would be a good way to test it? It has screw terminals so I could clamp the probes in and look for it dropping below 5v?

Thanks, It occurs to me that is has two output terminals and and a really unscrupulous manufacturer could claim 8A for something that is really only 3A sustained on two outputs?
I’ll try and probe the other terminal while pushing the limits of the other.
Report back tomorrow.

I’ve just been testing and voltage appears to be rock steady at 5.2V (at power supply output) and doesn’t drop even when brightness is pushed to full and ESP resets.

There is a trim pot for the voltage. If I adjust down to 5.1V it’s very unstable. Not sure how far up I dare try.
Edit to add: I adjusted it to 5.5V and have been able to raise the limit to 3500ma without resets.

Sounds like your wiring might not be adequate/too thin. There must have been a significant drop in voltage, the ESP32 should only become unstable if its supply current goes below 4.0-4.5V.
With the 5.5v you now set, try measuring the voltage at the ESP and/or LEDs. If it is below 5.0v, you should use thicker power wires to avoid them overheating.

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Hi Aircoookie,
Yes - this was the problem. In my eagerness to test it, I’d hooked it up with 3m of lighting cable.
Voltage at ESP32 was 4.54v. I have cut the cable down to 20cm and everything is good now.
Limiter set to 8000ma and no crashes. I can’t really see if it’s brighter as it’s such a sunny day!

It’s not the only mistake I’ve made with this one - Yesterday, when I first plugged it in,I couldn’t figure out why it would just run one pattern and then power itself off. I messed around for an hour unsuccessfully trying to change the presets but nothing would stick. Every time it powered on it did a preset and turned off.
Can you guess what it was?

I had another WLED install that was set to sync and powered off! Once I turned that on and disabled the sync it all worked. I had to laugh.

This is my third WLED light now - I will try and get some pictures of them synced tonight.

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Hi, I only have a slight guess as to why it would turn itself off… Maybe you have activated the Preset Cycle and set Set current preset cycle setting as boot default in LED settings.
Does the issue with running one preset and turning off still occur?

Does the issue with running one preset and turning off still occur?

No it all works now.
I think it was being turned off by another instance of WLED that was off. When I stopped that one from syncing it all worked as expected.

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