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How to design and build a switchable 3 colour LED into a 4x4 (16 cube) shelving system? Answered

Hi all, I've been wrecking my head on this project that I want to make, and I just can't seem to nail it, so hope some of you guys and gurus with much more electronic experience might be able to give me a nudge (or tell me that this is going to be borderline mental).

Background: I repair laptops and wish to make a lighting system to give a visual indication of my current work flow.
If a new laptop is placed in one of the 16 shelving cubes, I want to hit a switch on that cube to indicate the colour (RED), to say its a new arrival and hasn't been worked on yet.
After getting it on the bench for assessment, it will be returned to the cube in one of two forms, either A) Its unfinished and awaiting parts/customer communication (hit switch and show BLUE LED) or B) Its finished and ready for collection (hit switch and show GREEN LED).

The only thing close to an off the shelf (no pun intended) product that I've been able to find is 31cm wide Aquarium overhead LED for fish tanks. These come in at £11 GBP each, and I need 16 of the guys... so £176 to begin with as well as the issue with each unit having its own 12v Power Supply that needs plugged in! (Ouch).

So, can someone here possibly recommend a solution to this that A) Isn't going to cost me my first born child and B) Not use up every plug in the house! :D

I will admit, I'm actually not entirely averse to buying the 31cm bars as above, but would definitely need to be able to address the power requirements safely.

I'm really looking forward to your ideas or certainly if you know of any other off the shelf (still no pun intended) product that I could modify to fulfil my needs.

Discussions

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ThirdEarthDesign

Best Answer 3 years ago

If it were me I'd either use LED strips, single RGB LED's or separate R,G and B LED's, controlling them with PICAXE microcontrollers via a push button switch, probably work out cheaper than an off-the-shelf light strip with a controller or switch box, and the whole thing will run on 5v.

Even if you used one PICAXE microcontroller per cube you could still get the whole thing built for under £25. Or by using larger PICAXE chips you could control multiple cubes independently from fewer microntrollers, bringing the cost closer to the £15 mark.

Depending on your electronics skill level this may sound a little daunting, but it is simpler than it sounds.

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sheasmithThirdEarthDesign

Answer 3 years ago

This sounds great, wheres the cheapest for the PICAXE controllers though? I was looking on eBay and they work out at a £fiver a piece (16 cubes = £80) and I'd still need a way to power the lot, ideally at once, via one transformer/charger.

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ThirdEarthDesignsheasmith

Answer 3 years ago

The best place to buy PICAXE is direct from the PICAXE store

http://www.picaxestore.com/index.php/en_gb/picaxe/...

If you went for a larger chip you could do the whole thing with just two chips, or maybe even one. You'd power everything from a single transformer, anything capable of 5A would be plenty.

You can really make this as simple or as complicated as you want, the simpler / lower-tech approach would also be more than sufficient, I think.

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Downunder35mThirdEarthDesign

Answer 3 years ago

Why would you need a microcontroller to turn on a single color at a time for a single cube?
Sounds like total overkill to me ;)

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ThirdEarthDesignDownunder35m

Answer 3 years ago

I'd definitely agree that it's overkill when the same outcome can be achieved by just using simple mechanical switches. I only started using microcontrollers recently so I'm like a kid with a new toy, and I'm taking it everywhere with me!

Though it is worth noting that with the use of a microcontroller you could add extra functionality, such as blinking the LED's under different circumstances (i.e. when a particular cube has been in the same state for a certain amount of time etc).

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VygerVyger

Answer 3 years ago

By the way, a far simpler way is to get some different colored electrical tape and just put a strip of tape on the machine. Much simpler. The tape will pull off clean and leave no marks behind.

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sheasmithVyger

Answer 3 years ago

Do you know, you're right Vyger. Its lo-tech, and it might just be the easiest thing to do. I like the idea of the high-tech approach (especially given my business in repairing laptops etc), but for now, the tape will suffice quite well. :)

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VygerVyger

Answer 3 years ago

And another thing, tape doesn't use power so its a much greener solution than leaving lights on all the time.

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Downunder35m

3 years ago

IMHO the easiest option would be to use a RGB LED strip.
Since you don't really need a light controller I would go the simple way and do this:
Get a 5m roll of RGB strip (or more if you prefer).
Select a 12V power supply that is able to provide enough juice (IMHO a 5A type should be sufficient).
Now for each cube you add 3 switches to turn the color o you want.
Some of the LED controllers without strip go on Ebay for 5-10 bucks a small switch in bulk for a few cents - up to you how much you want to spend.
Don't go for the waterproof strips as they tend to overheat and fail premature.