Author Topic: 30AMP 12V power supply  (Read 1170 times)

Offline Michael

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30AMP 12V power supply
« on: November 19, 2016, 07:32:31 PM »
I am connecting 128 x 4 LED square nodes attached to the Falcon distribution board.  The board is connected to a 30AMP 12v power supply.  The fan does not run because according to the label, the fan only runs when there is heavy load.  Everything runs well, but the power supply gets very warm on the left side.  How can I tell if it is too warm.  All of the wires are cool to the touch. The label also says to avoid human touch. :)  I don't smell anything burning, and it ran fine for over an hour. 

Offline ChristmasBug

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Re: 30AMP 12V power supply
« Reply #1 on: November 19, 2016, 07:47:49 PM »
 Normally if it over heats it will either blow a fuse or turn off.. 90% of the power supply have a fail safe fuse so it does not burn up. Did you add a temp prong so it can tell how hot it gets?
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Offline Michael

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Re: 30AMP 12V power supply
« Reply #2 on: November 23, 2016, 09:26:38 PM »
I didnt add a temp probe.  Where can I find more information how do to that?  Thanks.

Offline w8one

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Offline gntoy

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Re: 30AMP 12V power supply
« Reply #4 on: December 16, 2016, 08:56:35 PM »
I found that the new supplies have a 65C vs older supplies with a 45C temp probe that tells the fan to turn on to dissipate heat from the supply. You can find the probes on ebay. Search KSD9700 45C

Offline Michael

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Re: 30AMP 12V power supply
« Reply #5 on: December 16, 2016, 10:38:22 PM »
Thanks.  I have two power supplies in a box and one runs the fan, while the other doesn't.  This helps explain why.

Offline corey872

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Re: 30AMP 12V power supply
« Reply #6 on: December 17, 2016, 07:12:43 AM »
I guess the other way to look at it would be to see what sort of amperage you are actually drawing.  Estimating with a standard 20mA per color per LED puts you at almost 31 amps assuming the string was all on, all white - though most likely the individual LED current is not that high and I suspect you don't run all on / all white for very long in a typical show.

128 nodes x 4 LEDs per node x 3 colors per LED x 20mA(?) per color

128 x 4 x 3 x 20 = 30,720mA, or 30.72 amps
Corey
 2018 uSC, Afterburner, uAmp co-op - pending May-June 2018.  Remaining boards are now FOR SALE

Offline jnealand

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Re: 30AMP 12V power supply
« Reply #7 on: December 17, 2016, 10:56:30 AM »
Thanks.  I have two power supplies in a box and one runs the fan, while the other doesn't.  This helps explain why.

If you have 2 power supplies in a box with one powering the left side and one powering the right side.  How many pixels are powered by each?  You may or may not want to move your connections to split the load evenly between the supplies.  Sometimes I do that sometimes I don't.  It's a personal choice.  I always say if it ain't broke, don't fix it.
Jim Nealand
Kennesaw, GA all Falcon controllers, all 12v Master Remote Multisync with Pi and BBB P10 and P5

 

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