LED blew up :/ 27 x 27 WS2812B array. 5V 60A Power supply.


I am making a light box with a 27 x 27 LED pixel array. I am using WS2812B strips, a 5V / 60A Power supply. I am using an H806SB LED controller to drive the LEDs. See pics for wiring. I am intending to use power injection but so far haven’t set that up.

I wanted to check if the LEDs would turn on so I have just loaded a test sequence onto the controller SD card and powered on the unit. The first row of LEDs lit up and displayed correctly but none of the other LEDs turned on. I thought this might be a bad connection between strips 1 and 2 so i turned it off and checked the 3 pin connectors that I am using (the pins are slightly too wide apart so I have been bending them into place)

When I turned the unit back on, the first row continued to run normally but then I smelt burning and the 5th LEDs on strip 2 began to emit smoke. I quickly turned off the power and now I am totally stumped as to what I should do next.

I think I must have wired something incorrectly and I’m worried I may have damaged all of the LEDs. :confused:
I need to have this project finished by Saturday so any advice would be greatly appreciated

What did I do wrong!?

(As you have probably noticed I’m not actually using Arduino for this particular project but I thought this forum would be the best place to find someone with experience of this, sorry if that breaks forum rules)

Are you purposely using 60A, or is that a typo.

Because if you are using that much then, I'm not surprised your lights blew up

Are you purposely using 60A, or is that a typo.

Because if you are using that much then, I'm not surprised your lights blew up

80mA per RGB LED sounds about right to me.

Are you purposely using 60A, or is that a typo.

Because if you are using that much then, I'm not surprised your lights blew up

My understanding is that the LEDs will only draw the amperage they need. So in theory you could run a single LED pixel using a 60A 5V power supply with no issues. For 729 LEDs I will be needing those high amps : )

As AWOL points out, 80 mA per LED x 729 = 58 Amps

each LED probably uses closer to 50mA at full brightness.

  • I'm doing some troubleshooting on this issue now, I will post my results just in case someone has the same issue and comes across this thread in a search. *

As far as I know you shouldnt push thrugh that much current on a small 24AWG(?) wire like those on the pictures, those only can handle upto 24amps if I have read that correctly. Furthermore I cannot see clearly from your pictures how you wired up the leds to the power supply and from that angle it looks like the ground and the positive is going on the same terminal.

Amazing set of photographs, you just miss showing anything actuall useful in almost every one.

Assuming that the voltage applied to the power pins of the strip is in fact 5V then the 60A capacity has no bearing on the problem. All it does is make any problem more libel to cause damage.

For an LED to fail in mid strip has nothing to do with wiring but the quality of the strip.

However do you actually need that much light for a light box? It it likely to burn your eyes out.

I would not chain the power like you do but run the 5V and ground down the strips on both sides.

It looks like just a chip failure. Is there burning on the back side? Bad luck, II would guess. Replace that strip with the last strip and try again.
In the future, I would only chain 2 strips at the most with power. You should have 14 separate sets of power leads from the PS, or single power bus with drops.
You should chain the data the way you have it.

OK, here we go:



Blown LED.jpg



power supply.jpg

Well, that LED certainly did blow, and the distortion of the strip itself suggests that the power traces overheated in the process - as one would expect. But why this particular chip?

I see no indication that it was assembled incorrectly, and there is no reason that the digital logic would cause it to overload, so we will have to deem it faulty - to proceed, you will have to cut out that segment and re-join the strip.

You seriously need to "bus" the power down each side of the array and feed power to both sides. Even if this LED had not failed, running anywhere near the majority of the LEDs would have caused a burnout. It is in fact, a slight possibility that the present problem is a crack in the ground or 5 V track just before the burnt-out LED.

Also your controller wiring is wrong.You have a separate power connection from the power supply, so that the data wire forms a large loop in combination. You need to power the controller ("powering" always means both 5 V and ground) from the start of the strip so that the data wire runs together in the same bundle as the power wires. It is somewhat inappropriate even that the data wire comes out of the opposite side of the controller, but you cannot help that - just keep the wiring all together.