I am in desperate need of help. I may be in above my head but am not going to give up.
Project: clothing that has about 600 pixel led lights or
2 x 16.7' ws2815 strips. It will be battery
powered, computer programmed and on
their own network.
I have only one strip setup on an arduino uno atm. The arduino is plugged into my computer. The 5v from the arduino is not hooked up to the lights. I have the lights powered by a 12v powerbank. Something is draining the battery at an epic rate. I cannot get more than 5 minutes before it dies and i have two different 12v powerbanks with the same result.
SOMEONE PLEASE HELP!!!
Oh, and i am a fashion designer so this is a huge learning curve for me.
There is not a lot you can do because these LEDs do take a very lot of current, 60mA per LED. So they will drain your battery at a high rate. So with 600 LEDs all on at full it will take 600 * 60 * 0.6 = 21.6 Amps! Which is a hell of a lot of current.
Even when the LEDs are off they still take 1mA per LED, so that is 600 * 0.001 = 0.6A for no light at all.
You can use the software brightness control to make the lamps dimmer and therefore drain the battery less. But apart from that the only other way is to design patterns that don't have a lot of LEDs on at the same time.
Why? Shouldn't it be 600 x 0.06 = 36 Amps?
@amygat78, you can measure the actual current consumption and depending on how long you want it to work calculate what capacity the battery should have. You may need to have a battery belt for the outfit.
Definitely going to have a belt with two batteries (one for each strand) and the arduino. I literally know nothing about the practical application of electricity. Can you guys dumb it down for me?
This is a pic of the front if it helps
Yes sorry it should be.
Remember that a belt is heavy and will get hot. Plus the fact you might get a suicide bomber vibe.
Well it is tricky. The problem is that the Maker movement, including Arduino seem to sell the idea is that you can do anything that you can imagine. They make little of the fact that all things are a balance between what you want and what is practical to do.
This often leaves beginners with the idea is that anything is easy to scale up, but in practice it is not. This is because other problems appear that you don't get with smaller scale projects. The two problems here are power, which you have found, and heat which is, I suspect, something you have not yet considered.
Let's assume you have just half the maximum load, which would be 36 / 2 = 18A. So powering this from 5V would give you a power of 18 * 5 = 90 Watts. Now not all that power is converted into heat, some of it is in the form of light. So let's assume the LEDs are 50% efferent in converting power into light. This still leaves 45 Watts of heat. Many soldering irons are less than this. So with half the lights on full (or the appropriate mix of lights on and not full on) the outfit is going to be very hot if worn for any length of time.
The art of design, as you will know, is mixing what looks good, with what is practical. That is the balance that you have to achieve.
One such thing you can do, as I said, is not have the LEDs on full brightness. Is the outfit intended to be used, indoors after dark? If so you will find the LEDs will be much too bright. You can use software to limit the brightness. However unless you post your code we can't tell you how to do this with the library you are using.
You might want to look at this How to get the best from this from this Forum before you proceed any further, as it tells you how to post code correctly on this forum.
Another thing that might be of concern is if this costume is to be used outside when it can be raining, so you would have to consider waterproofing. This brings another problem because this increases the thermal insulation and the temperatures of the LEDs could exceed that where damage starts to occur.
Do some web searching for
**wearable electronics **
so see the sort of things that can be done.
Any specific questions then please ask.
I believe the 12V WS2815 has the LEDs wired (and addressed) in groups of 3 in series. So 60mA can power 3 LEDs and the worst-case maximum would be 12 Amps.
But of course that doesn't change the reality that your battery is draining too fast. 
But if you look at his picture you will see that there are isolated pixels with a different colour, or two colour the same next to each other.
It is being used inside so that helps. I managed to figure out the power issue which is huge. The form vs function issue is age old and the balance is always hard. I push boundaries at all points bc why not. As of right now, I am terrible at coding and am running a few sample codes to get through this phase. Worry not, I have a programmer in the wings. I just need to figure out how to deal with the practical problems first. It can be done, the only real question is how to solve the next problem 
Because if you don't know what you are pushing you end up in a mess. It is a popular myth that pushing the boundaries is a good thing, but it takes skill knowing what you can push.
Lol. It takes a tremendous amount of work and a willingness to constantly learn. Failure is only learning how it won't work. I may fail a lot but that gets me closer to success. That is the process of what i do.
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