Powering long SK6821 strip with 24 volts

Other Hardware General Electronics
1

Hi,

this is probably a much discussed topic, I just couldn't find it here...

I'm working on a project where I use 10 meters of SK6812 RGBW strip (60 leds p/m) controlled by a NodeMCU (might become a Wemos D1 mini later on). Since each led is able to pull 80 mA and I have 600 of them, the total current could rise up to 48 Amps (240 W)!!! This would result in a HUGE 5 volt power supply and really heavy duty cables.

I thought of following solution:

  • Use a 24 volt/250 W power supply like this. This way I can drop the current to only 10 Amps
  • Add a step down converter like this each meter to power 1 meter of strip.

Am I correct that the cables used to supply the power can be way thinner then? (10 A at 24 V compared to 48 A at 5 V). Another advantage is that the powerbrick is way smaller :slight_smile:

Could this work? (I know I have to tie all negatives together)

2

Yes, that's the standard way to distribute power to reduce the amount of copper needed. Double the voltage means half the current and cables can be 1/4 the cross sectional area for same losses. Here you go from
5V to 24V, so about 1/20th the amount of copper is then needed.