Going to be building a new LED setup - is this power supply big enough?

[KoNP]

So I'm going to be running 4 Lumia 5.2 v2 pucks - 2 "fittings" running a pair in parallel, using 2 sets of 5 Meanwell LDD drivers (1 set per fitting). I need a power supply for these, though.

The technical details are as follows:

The LED pucks have the following setup

Channel 1 - (18v @ 700mA) (LDD-750) - 36v per string total.

Channel 2 - (16.5V @ 1500mA) - will be run at 1000mA - (LDD-1000) 33v per string total.

Channel 3 - (16.5V @ 1500mA) - will be run at 1000mA (LDD-1000) 33v per string total.

Channel 4 - (17.2V @ 700mA) (LDD-750) 34.4v per string total.

Channel 5 - (18v @ 700mA) (LDD-750) 36v per string total.

(the "total" figures are the puck string voltage values doubled, as I'll be running 2 in series).

Now, doing what little math I know, I've figured out that the total maximum wattage of what I've got planned would be a hair over 280w (280.4 or something like that). I'd rather use one power supply than two, so I'm wondering if this one: http://www.power-supplies-australia.com.au/single-enclosed-psu/sp-320 in the 48v version will be enough.

I'm not going to be running any fans off it or anything, just the LEDs, so there'll be no extra load on it. Also, my math didn't take into account the PWM dimming on the drivers that will result in them probably only running at 75% of what the drivers can output maximum (as they're quite bright).

So does my math hold? Would a 320W power supply stand up to that? Or should I go higher? Because the next step up is nearly twice the price.

 

[Gorgok]

Basing it off wattage is not the best way to go about it. You need volts and amps, wattage is just whatever those multiply into. The 48V version is capable of 6.7A, and if i understand your numbers right you will have 2 of these, so 2 x (700mA + 1A + 1A + 700mA + 700mA), or 2x 4.1A = 8.2A.

The 48V driver can't do that, even though wattage wise it might be fine.

The 36V version might just squeeze by, if you really can turn the voltage adjust up to 39V as the specs say, and your pucks only use 36V max (so the LDDs have their 3 too). But even then you are asking for 8.2A from a supply with 8.8A rating. With dimming it would be less load obviously, but fully driving the 8.2A at 39V would net you 319.8W out of the supply... full blast essentially. Something beefier would probably be in order, really.

 

[KoNP]

Basing it off wattage is not the best way to go about it. You need volts and amps, wattage is just whatever those multiply into. The 48V version is capable of 6.7A, and if i understand your numbers right you will have 2 of these, so 2 x (700mA + 1A + 1A + 700mA + 700mA), or 2x 4.1A = 8.2A.

The 48V driver can't do that, even though wattage wise it might be fine.

The 36V version might just squeeze by, if you really can turn the voltage adjust up to 39V as the specs say, and your pucks only use 36V max (so the LDDs have their 3 too). But even then you are asking for 8.2A from a supply with 8.8A rating. With dimming it would be less load obviously, but fully driving the 8.2A at 39V would net you 319.8W out of the supply... full blast essentially. Something beefier would probably be in order, really.

That makes a lot of sense actually.

Two of these ones would be better, from the sounds of it: http://www.power-supplies-australia.com.au/single-enclosed-psu/sp-240

That would give me enough headroom, even though I'm unlikely to run the lights at maximum. It'd also let me have a dedicated psu for each light fitting, so if one busts at least I'll have the other one. Plus overestimating psu size is better than underestimating.

 

[oreo57]

never mind..but do remember the Ldd's require a 3-4V differential.. If you need 33V out the ps needs to be 36/37V

You need volts and amps, wattage is just whatever those multiply into.

If you think about that it is a bit funny..

anyway, the orig PS is fine for ONE set:

Channel 1 - (18v @ 700mA) (LDD-750) - 36v per string total.

Channel 2 - (16.5V @ 1500mA) - will be run at 1000mA - (LDD-1000) 33v per string total.

Channel 3 - (16.5V @ 1500mA) - will be run at 1000mA (LDD-1000) 33v per string total.

Channel 4 - (17.2V @ 700mA) (LDD-750) 34.4v per string total.

Channel 5 - (18v @ 700mA) (LDD-750) 36v per string total.

39V minimum ps w/ 4.1A output..Your actual voltage (thus actual watts) will vary by the actual V(f) at that drive current..

ODDLY enough China seems to be selling some w/ the specs you need

New 40V 10A 400W DC Regulated Switching LED Power Supply CNC WITH CE
$58US ............

and to be perfectly honest.. I'd order 2..