Hello Friends of the forum, I am starting in this world of led strips,

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(Carlos “ALDI” Reyes) #1

Hello Friends of the forum, I am starting in this world of led strips, recently I bought a led strip ws2812b of 5mts and 300 leds, eh used the recommendations to incorporate a capacitor of 1000u and a resistance for the data channel, to feed them I use a computer atx source, however a problem arises when I illuminate the entire led strip in white rgb (255,255,255), the first leds look white almost halfway through the strip they begin to turn red until the end, do you think it is a power problem? Does the atx source not provide enough amperage? Thanks

(Marc Miller) #2

What you are seeing is a voltage drop over the length of the stirp. Use a multimeter and measure the voltage at both ends and you will see the difference.
To fix this you need to inject power at multiple places along the strip to keep the voltage at 5V (or very close to 5V).

(Carlos “ALDI” Reyes) #3

@marmil Thank Marc, Do you think it is possible to feed the strip at both ends? Can not a short circuit be produced, or is there a scheme that can share me to feed correctly on both ends?

(Marc Miller) #4

In a case like this where you are getting too much voltage drop you should feed it power at both ends, and maybe one or more places in the middle as needed. You will have to experiment and also consider how bright you need to run the LEDs. If you don’t need to run them at full brightness you can probably get away with less injection.

(Carlos “ALDI” Reyes) #5

@marmil Thanks Marc

(Marc Miller) #6

One example:

But you don’t need to cut the strips as they have in this drawing (unless you are using separate power supplies). And you can run the power to the end too if you want. Whatever makes it easy to wire is often a factor.