Power, power, power… who has managed to drive a matrix 144x144?
I saw at http://deskontrol.net a LED controller that is able to drive a 512x512 matrix… but what about the power?
Has any of you gone into power 20K leds? What did you do?
WOW, I think you need to knock on some industrial PSU manufacturer’s door for that !!
I have some idea on what to do, I just don’t want to re invent the wheel if already something in place.
There is a MAX16818 IC that can be easily integrated that draws up to 30A, but that means at least 40 of them for that big one.
@Victor_Pacheco Just checked that device and it is a DC-DC conversion IC.
It still leaves you with the need to supply it with some DC volts with high currents !!
I have seen 5V 100A PSUs on eBay for about $100US, you would need about 10 of those !!!
Divide and conquer, my friend. You’ll want a whole bunch of 5V 20A supplies. Why 20A, specifically? Because they’re reasonably small and are easy to arrange! Also, if one PSU goes it’s a lot cheaper to fix!
Trying to do it all with one PSU is a mistake.
@Dan_McDougall , that would also work but the footprint of 5 20A Psus is considerably larger that a single 100A PSU !
@JP_Roy Well, only marginally so because those 100A PSUs have some pretty serious cooling requirements. They’re thick. The 20A PSUs are nice and thin so you can cram them into a tighter space.
Hi @Victor_Pacheco , I am curious to find out what is purpose of this huge undertaking and would definitely love to see the finished thing!
Also, what type of RGB LED, and in what package, strip or individual pixels ?
@JP_Roy I am trying a matrix display in two versions: fixed and movable. This will require AC and DC inputs up on the version, but there may be attached an AC-DC psu.
I am using WS2812 and/or AP102
AP102s are awesome. I used some in my Christmas lights display last year.
Do you have a good outlet to drive this?
Whatever approach you will end up with you got at 90% efficency at least 1100 W input what calls for an 50A breaker.
For 50A @ 120V you need a 4AWG cable !
Looking for a 5V 1000A supply: (230V input !)
http://www.volteq.com/volteq-power-supply-hy051000ex-5v-1000a-over-voltage-over-current-protection-220v-input.html
or: http://www.ebay.com/itm/Hewlett-Packard-HP-6464C-DC-Power-Supply-0-8V-0-1000A-/111766594649?hash=item1a05cee459
The real fun starts on the 5V side: If you get yourself a fat welding cable with 120mm² (250kcmil) and choose only 1m length to your installation, do your math:
1m (~3ft) = 2m round trip
R-cable = (Rho-copper x lenth) / cross-section
R = (0.0176 x 2) / 120 = 0.000293 Ohm
Voltage drop = R x I = 0,293V
Sounds not much? Then calculate the power that you are burning in the cable:
P = 0,293V x 1000A = 293W
120mm² cable is rated up to 344A, so you need 3 pairs of that cable and end up with 100W burned.
You should look for 1 x 1 inch copper bars bars instead.
Maybe 20A - 100A PSUs are the better choice.
However, keep in mind that you need a serious power outlet at the point of installation.
Good luck !
Hi @Juergen_Bruegl , Very good point about the AC outlet and cabling requirement and you will probably get closer to 80% efficiency with the more basic, low-cost PSUs.
As suggested by Dan McDougall, I would also definitely not go for a single 1000A PSU for this. Distributed 20A to 100A PSUS are a lot more practical and would help with DC wiring size requirements also.
http://www.trcelectronics.com/5-volt-power-supplies-chassis-1.shtml
Trc is great, super organized site, every thing ranging from a couple amps to several hundred.
My favorites I’ve used several times now are there 60amp and 100amp ones, I think pages 3,4,5. The 60 is pretty tiny too!
@Lucas_Morgan seems like the highest output they have is 10amps. I purchased one from ipixelleds @250W (50A) for usd 30
Hi @Victor_Pacheco , $30USD is a really good price for a 50A PSU.
I think you only looked at page 1 of that catalog Lucas gave you. There are other pages… but they are all a bit pricey. Are they better quality !?
Yes thought… I looked at that. It is a NES-350-05 meaning it is a 350W @5V so 70A instead for 27.50 usd.
@Victor_Pacheco yep, multiple pages. They’re high quality, and a lot of built in protections for various things like over voltage, reverse polarity, heat, etc.
Theie highest dc 5v PSU is 300 amps! Insane. I’ve used their 250 amp one and in all honesty it can be a fire hazard and annoying in other ways to deal with one big PSU.
Several smaller ones is a pretty good way to go, just need to keep the positive DC ends separated and keep grnd common.
This is the 60 amp one I mentioned for $38 bucks, love the form factor too. so much good technical data in the data sheets too!
http://www.trcelectronics.com/View/Mean-Well/LRS-350-5.shtml
I have done 16,000k with 10x 350W 5vdc PSUs. Just have to tie together all your grounds. I never showed white in my code and it had custom animations that I was sure would never be the peak power usage. Melted a power connector or two at the PSU… And have since decided if I did it again to go up 1-2 PSUs on that same setup to bring down the load on the PSUs and wires a bit.
From ScottLED in China, I get 5vdc 70A for $16.13… but then you have to ship them… cheaper if your buy more than 1 or 2 than I can get here in the states. Never had a failure…
As mentioned by @Justin_Eastman , your calculation above is for a worst-case scenario, which is all pixels totally white at full brightness. If you never actually want to do this (and you probably don’t—it would be painful to look at!) you can get away with considerably less.
If you have an iPhone, have a play with LEDstimator (https://appsto.re/us/AV6x4.i). You can use it to play with “What if” scenarios around pixel count, brightness and pattern density. #plug