WLED controlled light up angel wings - help and advice please

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21

I kinda get what you mean.
But practically, in that diagram, where would that wire go?
I have the 5v +/- into the microcontroller, then the data from the controller to the LED start, along with power 12v +/-, at the end of the LEDs the power 12V goes to the battery.

Does that mean I need to have the data cable at the end of the LEDs go back to the controller? Or to the battery? Or the 5v converter?

22

One way is to connect a spare ground on the MCU to the ground distribution point at the battery. The simplest would probably be to just connect the ground on one end of the converter to the ground on the other end of the converter. But note that this may not be needed; most converters do not have an isolated ground, and it is likely that the ground is already the same for input and output. With the converter disconnected, just check with a multimeter to confirm that there is full continuity between the two grounds.

If you don’t have access to a multimeter you may be able to confirm that the two grounds are connected by following the traces on the board - the ground trace is usually easy to follow. Or post a link to the converter you are using and someone might look it up.

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23

Hi Matt

No to all of that. I was talking about the ground NOT the data line., wire that as you have shown.

Heed what Jeff has posted. It is highly likely that the ground connection DOES carry through on the board. Easy enough to check. If you are still unsure just connect a wire from the Gnd on one side of the converter to the Gnd on the other side. You will have to check this as I don’t think anybody but you (a secret maybe) knows exactly which converter you are using.
Cheers Bob

24

Oh, I don’t know what specific (brand etc) pieces I am using yet.
I am trying to make sure it is possible and I can do it before I order anything.

So basically, it should be fine, but if it isn’t, ground to ground on the microprocessor to check?
Then it’s an easy fix, and if I posted photos of the actual stuff you could point me in the right direction?

25

Oh! This is a store! I didn’t realise, I just searched for electronic forum on Google and found this, because Reddit was beyond unhelpful.

Feel free to use parts that this store sells as examples.
You guys have been very helpful, I probably should buy here too

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26

Hi Matt
Nobody said Gnd to Gnd on the microprocessor. That WILL be connected.
I will say it one more time, it is the Gnd to Gnd on the converter that should be checked otherwise there will be no Gnd return path for the Data signal if there is no connection here. That is according th the diagram you posted. If as you say you haven’t purchased one yet just get one that has a common ground.

Have you got a multimeter and know how to use it. This would be helpful to know.

Maybe you should.
Cheers Bob

1 Like
27

This is an example of a converter that is not isolated, and therefore does not need the additional connection between the grounds.

From the datasheet:

Electrical Parameters
...
17 Isolation or not          Not isolation

Pin Definition
Order Name Orientation Use 
1、2   Vo +  output    Output power supply positive 
3、4   Vo -  output    Earth wire, output port power **Reference Ground**
5、6   Vin - input     Earth wire, **link to power reference ground**
7、8   Vin+  input     The maximum input of power supply is 28V,Over 28V will
damage module

(Emphasis added)

28

Sorry yes, converter is what I meant.
Thank you

I realised I have bought PLA from here before, probably why the algorithm gave it as top result when I searched

29

Hi Matt

If you want meaningful results from the forum you will have to be a bit more accurate. read that as very accurate and complete. this sort of thing can cause confusion and waste a lot of time with repeated replies like just now with quoting processor when you meant converter. A little more care here can save a lot of heartache.

What is “PLA”, to the uninitiated and uninformed it might as well be Swahili.
Cheers Bob

30

My apologies. A million different new-ish words running through my brain.

PLA is 3d printing filament

31

Hi Matt
Accepted.

That jogged the old grey matter. I realise now what it is, I have not had much to do with 3D printers so it is not a term that rolls off my tongue very often if at all. That is another field which is accumulating lots of bits and abbreviations and if not involved is a bit hard to keep up with at times. I believe it is an abbreviation for some long winded name for the actual material, like PVC.
Thanks for that. Cheers Bob

32

You are correct. Polylactic acid

As you can no doubt tell, the electronic learnings have sprung from that. (The wing frame will be printed).
Words and formulas are bursting around my brain as all the stuff I learnt in the 90s pops back into place.
I hated it then though, we didn’t do anything fun. Just If and or switches on breadboards and lots of math. Then we made a box with 1 flashing LED, and class over