Connecting 2 HKBAYI (Neopixel) Strips Together

I am trying to make some room lighting and a I have two of the HKBAYI strips connected in parallel. Together they draw too much power to be run off of my arduino mega alone. I have a 5V 10A power supply that I have connected to the +5V and GND and the data is connected to the arduino.

I am using the test program from the neopixel library "strandtest".

The problem is that when I turn the circuit on the lights do not follow the program, they just appear to be changing randomly, but only 3/4 of the way down the first strip. Is there a reason for this?

When you give us a picture of your whole setup we will know.

Here is a picture of the setup. The black wire is ground, orange wire is +5V and the yellow is the data pin. Sorry its not a very good picture.

20190302_174316.jpg
The picture will do. I can't see your LED strip ground connected to the Arduino. :astonished: Any electrical circuit requires two connections.

You should use the free white and red wires to connect directly to that screw connector. A 470 µF capacitor also connected in parallel there would be a good idea.

The white and green wires of the JST connector then connect to ground and data on the Arduino.

You haven't given us a link to these LED strips. If they contain more than 30 LEDs, you must connect the power in parallel at least every 30 LEDs along.

I modified the circuit as you said and it fixed the random lighting. This set up works to run one strip just fine, but when I try to add in the other strip the program seems to stop and start over in the same point every time, about 3/4 of the way through the first strip.

What exactly is the reason for providing power every 30 LEDs? That would be rather difficult with these strips being covered. Would being powered at each end do a similar task? Each strip is 240 LEDs long.

Link for LEDs - https://www.amazon.com/gp/product/B00K7UHPEC/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1
Picture for New Setup in attachments

KelseyS:
I modified the circuit as you said and it fixed the random lighting.

As it should.

KelseyS:
This set up works to run one strip just fine, but when I try to add in the other strip the program seems to stop and start over in the same point every time, about 3/4 of the way through the first strip.

So we now need to see your code, posted in "code" tags according to the instructions. First thing to check is that you have set the correct number of LEDs. :astonished:

Oh, wait, you say it does work with one strip? Right! Next two points:

KelseyS:
What exactly is the reason for providing power every 30 LEDs? That would be rather difficult with these strips being covered.

So they all get five Volts. :grinning: The less they get, the less reliable they are and less able to show correct colours.

KelseyS:
Would being powered at each end do a similar task? Each strip is 240 LEDs long.

That would be the absolute minimum. It's also why they have the red and white wires at both ends. :sunglasses: If - when you get it working - it fails to show white away from the power when all white, then you may need to modify it further.

240 LEDs? 14.4 A on full white. You may think you never need full white, but if it gets sent at some point, even briefly, and the power supply cannot provide that, well what do you will imagine will happen?

KelseyS:
Link for LEDs - https://www.amazon.com/gp/product/B00K7UHPEC/ref=ppx_yo_dt_b_asin_title_o02_s00

Link corrected.

can work on USB power

Total rubbish! :astonished:

KelseyS:
Picture for New Setup

Where?

Thank you very much for your help. I think my next step is to get another power supply to be able to add power to each end of the strand. Will update once I get another one on.
And the picture was attached in an additional file, not sure why you couldn’t view it. I’ll try to add it again here.

KelseyS:
Thank you very much for your help. I think my next step is to get another power supply to be able to add power to each end of the strand. Will update once I get another one on.

Now hang on!

You need to put power to both ends of each strand with the same power supply. Some people here strongly advise against attempting to connect two power supplies in parallel though at opposite ends of a strip would arguably be reasonable as the resistance of the strip itself would distribute the load.

You need a decent cable running from the power supply (both wires of course) to the other end of the strip as well as the first end - at least 1 mm2 cable. If you get a second 5 V 10 A supply, use it for - both ends of - the second strip. Use the white and red wires, and the second strip plugs to the JST connector of the first with the red wire removed! That is, ground and data only. And you should put another 470 Ohm resistor in series with the data wire. Why? Well, (Grumpy) Mike points out that if the second strip is powered down, the first will still try and drive it which is not a "good idea".

KelseyS:
And the picture was attached in an additional file, not sure why you couldn't view it. I'll try to add it again here.

Ahhh, now it's there!
Arduino LED setup2.jpg
OK. You should not be connecting the 5 V from the strip back to the UNO unless the USB is disconnected. There is a risk that feeding 5 V into the computer's USB may upset it. Note what I said previously:

Paul__B:
The white and green wires of the JST connector then connect to ground and data on the Arduino.

With digital devices, precision is important. I said something that was intended to be very precise; I deliberately did not mention the red wire! :astonished: