Hello, can anyone help me? I have WS2812B connected as shown below.

(maris ancans) #1

Hello, can anyone help me? I have WS2812B connected as shown below. I have working animations, however they all are red, green color is barely visible and there is no blue color at all(led strip shows nothing at all), as a power supply I have 4 AA batteries, each 1.2 V connected in series (4.8V), I have 30 leds, im using NODEMCU v3 to controll it. I cannot wrap my head as to what could be the cause of it.
here is the code https://pastebin.com/RETPMF5i
If anyone could guide me to what could be the reason I would be greatly thankful, this is a simple task, but I struggle so much.

(Jason Coon) #2

Sounds like a power issue. Do you have a proper 5V power supply you can try? You might also try lowering the brightness, and powering the LEDs from the Arduino’s 5V pin (with the brightness turned way down).

(maris ancans) #3

@Jason_Coon I don’t have 5V power supply but I will try and get one and I only have my nodemcu aviable, but I will try your suggestions. I also red on the internet that this might be a power issue, just don’t know how to test it, have to finally buy voltmeter.

(Jason Coon) #4

@maris_ancans ah, sorry, missed that you’re using a NodeMCU, saw “Arduino” in the drawing. :slight_smile:

For the NodeMCU, you should be able to use the VIN pin to power the LEDs. This should be 5V from the USB cable.

Definitely try adjusting the brightness down in code: FastLED.setBrightness(16)

It’d definitely help to have even just a basic $10 multimeter like you can usually find at most hardware stores.

(Marc Miller) #5

@maris_ancans If you’re making a portable or wearable project consider getting something like this for power. They are very convenient to use and will power your 30 LEDs (and controller) for hours and hours.

Jackery Mini 3350mAh Portable Charger Battery Pack

(Tod Kurt) #6

This definitely sounds like you’re powering the strip with 3.3V instead of 5V.
The more towards blue you go with LEDs, the higher the voltage you need to turn them on. This chart is pretty good showing the relationship:

(from https://kithub.cc/2015/11/how-many-volts-are-needed-to-power-an-led-2/ )

(Marius Kohsiek) #7

How many led are there on that strip?

(maris ancans) #8

@Marius_Kohsiek 30 leds, they are packed together quite close, the strip is like 30cm long

(Marius Kohsiek) #9

@maris_ancans What type of cells did you use ? 1,2V sounds like NiMH type. Such type of accumulator should handle 30 LED pretty easily… (assumed 50 mA per LED x30 = 1,5A in total)

(maris ancans) #10

@Marius_Kohsiek Yes, these are Ni-MH batteries, I will try and charge them, maybe thats the cause. I also ordered 4 of 18650 batteries as this project has to be portable, my idea is to user 2 of 18650 in series and then a buck step down converter to put out 5v, is that good? Sorry for asking but I really have no idea what im doing

(maris ancans) #11

The problem was as you guys told me - power, charged my batteries and everything works, such a stupid mistake, thank you for your time

(Jason Coon) #12

@maris_ancans no worries, glad you got it working! Looking forward to seeing pictures and video of your project!

(Marius Kohsiek) #13

@Marius_Kohsiek If you would know how many stupid things of that kind I did in my life :slight_smile: Each of them is an opportunity to learn…

Assembling a step down converter with 2 Li Cells in series to produce 5V is a nice solution with high efficiency, especially for your purse. Dont forget the balancer circuit to prevent firework at charging :slight_smile: