for my son, I plan a little project:
On his wall, he wants a stripe in the shape of an X, but the two sides of the X shall be offset by another stripe.
\__/
/ \
The middle bar shall be 70cm, the four elements of the shall be 35cm.
It shall be ambient lighting only. My Questions:
30 or 60 LED/m? or even more?
Pure ESP8266 or one of the many boards?
I see that some boards have a relay to cut the power to reduce standby consumptions - how much is it?
Do I need the levelshifter in this case?
should I put it in/on aluminium for better cooling? The actual shape will be wooden.
can I supply in one of the corners, or should I supply the voltage in the middle?
is it possible to visualize that shape in WLED and to animate it properly that way? I.e. the upper and lower left part of the X first, then the middle part, then the upper/lower right part of the X?
Thanks for your patience with me - I am a novice, as you can tell…
Depends on how bright you need the final product to be. Are you lighting the room with this or is it just an interesting feature? Roughly speaking,
your dimensions 35cm+35cm+70cm+35cm+35cm=210cm => either 63 or 126 LEDs
At maximum brightness you can expect something like 0.2-0.3W/LED (depending on what you buy)
So you’re looking at 12-18W or 24-36W, you’ll have to decide if that’s enough for your needs.
A secondary issue may be how many LEDs you’ll actually fit in the sections of your shape and you may have to adjust up or down.
For a new build, I would recommend an ESP32 based board. There’s almost no cost difference and the future capability of the ESP32 is well worth it. As far as standby power for the LEDs, I have measured it to be typically 1mA/LED. Your setup would be on the order of <150mA. Unless this is battery powered, I wouldn’t worry about it, you’re talking less than 1W of standby power.
Levelshifters are recommended regardless of your power setup, they translate the 3.3V output of the ESP’s to the 5V level the LEDs require. The power required for the shifter is negligible.
Given the power levels described in 1), you’re talking about a worst case of 36W spread over 2+m. That’s not a lot of heat to worry about, I’d be comfortable without any extra cooling on this one.
You might get away from powering in a corner, at 36W max you need 7+ A of total current (5V LEDs), but your runs are small. A better solution would be (labelling the vertical bars A,B,C,D and assume the horizontal bar is E:
A\__/B (E horizontal)
C/ \D
Powering at the A-C-E or B-E-D junctions will give you much more even power distribution. It minimizes the maximum length of strip you need to power down to 1.05m. It does mean the E section needs to supply power to 2 legs (either A,C or B,D). Probably you’ll be OK for these short runs.
You can definitely use Ledmaps to change the order that the strip is displayed, see the KB: Advanced - Mapping
Keep us informed with your progress and I’m sure some can help if you have more questions
thanks so much for your detailed reply!
Regarding ESP32 vs 8266:
I have plenty of 8266 lying around, that’s the reason to use that one.
Do you really think, that this little project would benefit from ESP32?
Regarding level-shifter: The problem is just, that the more pieces you have, the more cables you have, the more you need to hide and the more sources of error you have. Thus, I would have hoped to get away without the shifter.
Also, when adding the two above points up, I’d go for a ready-made controller. But that would cost my son 20-30$ / € that I’d like to avoid.
But if it is needed, we’ll go that way. What do you think?
Depending on the distances from the controller to the 1st LED and/or the type of LEDs, you might get away without the shifter. If you’ve already got the pieces it’s worth a try. It won’t hurt the LEDs to run without, you may get flickering or other issues.
@divsys I think that the mapping is not sufficient. I want to use effects that move from left to right, but also effects that move from top to bottom or diagonal.
Do I see it right, that I need this 2D Support - WLED MoonModules Project ?
Is there an example of a 2D Mapping somewhere? The description is not fully clear to me.
Also, I suppose that for this setup, I need to not connect the D and B string data lines at the junction (a Y-junction) but need to make sure that the data-lines are without junctions (one line), even if the physical layout (and power supply) has junctions - right?
You can have different mappings for different presets, so you should be able to customize it however you like.
2D support is also available in the standard builds as well.
As long as you don’t connect 2 (or more) Data In points to the same GPIO, WLED can always treat the setup as one continuos line. You can of course use multiple GPIOs from one ESP32 to drive different sections. WLED will still let you treat that as one continuous strip.
