How much is too much?

sck1ng

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Oct 23, 2013
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I was wondering at what level you should bring a power supply up to maximum? I have three elements I wanted to do off one controller but I'm afraid I might be putting too much stress on the power supply. The elements are 420 pixels total. They are 12v .72 watts .06 amps per pixel.
 

logandc99

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Jul 13, 2012
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Generally people suggest no more than 80% max for a typical ray Wu power supply but you can go a bit higher with quality meanwells (I leave that value up to those who use the meanwells like Fasteddy).
 

logandc99

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ShellNZ said:
Milk that puppy for all its got I say :)
[emoji95][emoji91][emoji1]. Especially if your sequencer can't make a nice flame effect with the lights.
 

sck1ng

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Oct 23, 2013
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Thanks.. I have ordered a few more power supplies to cover a couple things I have left to do.
 

David_AVD

Bite my shiny metal ass!
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Something to keep in mind is that a power supply with 320 (for example) in the model number may not actually be rated for 320 Watts.

For example, a Mean Well SP-320-12 is rated for 300W and the SP-320-5 is only 275W.
 

i13

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Don't trust the LED current and wattage ratings on the AliExpress listings. They're typically overestimates. If the actual current draw turns out to be too much then just use power injection from another supply.
 

damo1271

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Oct 12, 2011
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With the Chinese power supplies I always budget for an average load of 1/2 the rated power supply capacity. So a 5V 40A (200W) "rated" supply I will generally try and work it so the average load is not more than 20A.
This seems to work OK for me and gives some redundancy as well.

I am convinced the Chinese just make up the power ratings for their power supplies and give them the biggest number they think they can get away with.
In Australia misleading and deceptive conduct is illegal. For some Chinese companies I think it is their business model!
 

Fing

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I have bought some chinese power supplies. two 5v 60Amp - I put them under a full load test and I could only get 55A out of one and 36A out of the other. I "repaired" the low one by borrowing from the other, they now do 50A each.
Two 12v PS, rated at 33 amps each used 30A components. One blew up when accidentally shorted, :( .


So even if you have a "rating" on the outside and you try to run it at max, the Max may not be what you think
My answer, buy proper meanwells... 2-5year warrantees


Cheers
Fing
 

plasmadrive

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Jan 12, 2012
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Elk Grove, CA
The supplies I use are 100% rated.. I push them all the time without issue.. But I use 24v and convert at the pixel prop to whatever voltage I need.
 

Greg.Ca

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Jan 1, 2013
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I would agree. There are places to skimp and this isn't one of them. I would say paying a few bucks more for a good REAL meanwell rather than a Chinese lookalike would be the right thing to do. I use Real meanwell's from a reputable distributer and probably pay double. However they ship from America to America and I'm not paying for international shipping charges. To me it's a no-brainer. Remember what my kids father always says: "Long after you forgot what you paid for it, you remember the quality". That can be said of most things.

Remember 'white' is the enemy of your power supplies. When a pixel is at full white it is using somewhere close to 60 ma of current. Pure red, pure green or pure blue only uses 20ma of current even at full brightness. Use these colors liberally. When displaying pics, movies, animation or graphics on a matrix or mega tree, make sure the 'background' is not white and if possible turn down overall brightness for better resolution and lower current. Black background(darkness) is preferred as black uses NO current and keeps average current lower. White is ok but make sure that ALL pixels are never ALL white as that stresses the power supplies to their max. It's the 'worse case scenario' for pixel power supplies.

Just my .02 cents worth. --Greg--
 

fasteddy

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With good design you never run things to their maximum as you reduce the life and increase the chance of infantile failure. Some people want to draw every last watt from their power supplies because they have tight budgets, but by doing this it may in fact cost you more in the long run due to early failures. So with most of the cheap Chinese power supplies then always design for a maximum of 80 to 85 % of the rated load when you have the lights on white. This ensures you will not be over stressing the power supplies as long as you don't continually use white the whole time because when we use Red, green or blue we will only be drawing 1/3 of the calculated maximum current and 2/3 if we use colours like purple, aqua and yellow which are 2 colours
 

Gilrock

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I have both types of supplies and besides the label you wouldn't know the difference except that the Meanwell's annoy me because they seem to run the fan 24/7. I like the Ray Wu supplies that only run the fan when needed. By the way 92% of Meanwell's are made in China so these are pretty much all Chinese power supplies.
 

ShellNZ

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Here here Gil, my one Meanwell is super annoying and loud. My other 432 Chinese ones are super and no failures. I was just kidding before, I dont go over 80% :)
 

Gilrock

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Yeah I've been using one for testing in the house and I was like OMG can you make a fan any louder than that.
 
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