Need guidance for selecting appropriate power supply and for connecting a lot of LEDs properly

@ gilshultz 9 volt 1 amp wall-wart power supply worked OK for 1 hour without heating Arduino Nano's voltage regulator. Now i want to know one more thing, "Can i use 5 volt directly from main power supply (5v 30a 150w) to connect it to Arduino Nano's +5v pin, just as i have shown in the image below?"

It should work just fine!

Hi,

Yes, BUT put a fuse in line with the Nano and/or your project, so if you have a short on your project you do not blow the PCB and controller to smithereens with the full 30A from the power supply.

Tom... :smiley: :+1: :coffee: :australia:

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That would be what I recommended in #13. :roll_eyes: It makes no sense to use a non-5V power supply if you already have the proper 5 V power supply.

Note however that I explained some important things about the layout of the wiring, not quite the way your diagram indicates.

@gilshultz Thanks for your guidance :slight_smile:

@TomGeorge I will follow your advice for sure. Thank you :slight_smile:

But that 5 volt comes with way higher amps; So i was bit scared to run Nano with it. Yes, i will surely follow your guidelines. Thank you very much for spending your time helping me and others.

So here i have exactly 540 ws2812b led lights mounted in “L” shape on the edge of the main roof of my house. Now can someone please tell me where can i learn creating my own sketches/codes. I mean if there is any book available on this subject, then i would like to read it.

Yes, we get this here a lot.

The answer goes like this: My power outlets in the house are rated at 240 V, 10 Amps. I can plug in a toaster that draws 10 Amps, or a heater, it is rated at 2400 Watts.

I have in front of me an Ikea LED light which is 3 Watts. This means the power supply needs only 3 / 240 or about 12.5 milliamps.

How then is it safe to plug it into my power outlet which comes with way higher Amps - 10 Amps, eight hundred times as much in fact?

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The power supply only takes what it needs. For an analogy, you go to the sink and get a glass of water, no problems. You have thousands of liters available at many atm pressure why was the glass not blown out of your hand? You do the the control with the faucet. The power supply only takes what it needs by controlling the flow with electronics. There are several books on basic electronics that will explain this.

The power supply load only takes what it needs. For an analogy, you go to the sink and get a glass of water, no problems. You have thousands of liters available at many atm pressure why was the glass not blown out of your hand? You do the the control with the faucet.
The power supply load only takes what it needs by controlling the flow with electronics due to its resistance across the power supply terminals.
There are several books on basic electronics that will explain this.

Say you can have a 240V 10A power supply.
Your load can be a 240V 2A lamp and it will only draw 2A from the supply at 240V.
Your load can be a 240V 8A lamp and it will only draw 8A from the supply at 240V.

What it is advised not to do is make your load 240V 15A lamp, as it will try and draw 15A from the supply, this is an overload condition.
Power supplies have different ways of dealing with the 15A overload.

  1. Some lower the output voltage until only the rated 10A flows.
  2. Some shutdown to zero volts output, requiring a power supply OFF/ON to reset.
  3. Some shutdown and briefly cycle ON/OFF checking if the overload is still there, if not then the supply restarts. (They tick..tick.. tick..)
  4. Some blow a fuse.
  5. Some just let the smoke out (A very effective method as it notifies the Audio, Visual and Olfactory senses.)

Tom... :smiley: :+1: :coffee: :australia:

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@Paul_B Do you think, It is more proper to power Nano through a 5v 30a 150w power supply using Nano’s +5v pin than powering it through a 9v 1a wall-wart power supply using Nano’s VIN pin? If yes, then can i please know why?

Do i need to start a new topic for my #28 post? And do i need to post it under “Programming Arduino” section of this forum?

Absolutely. See #24. Also avoids the risks of having one supply turned on while the other is not.

Note that you must run the three wires all together - as a bundle or single cable - from the start of the LED strip where the 470 Ohm resistor is, back to the Nano; the ground, the data wire and the 5 V power for the Nano. And just in case, since these are much lighter gauge wires than the main power that is connected into the LED strip every 50 LEDs, you also put a 1 Amp fuse in series with only the 5 V connection for the Nano, at the LED strip.

If it is for an entirely different project, Otherwise it would constitute a "cross" posting duplicating information on the same project and would automatically (once reported as such) be merged back to this post.

Not if it is for guidance on your project. :grin: