Stranger to LDD drivers and needed power supply

[Daimyo68]

I've built more LED fixtures for fellow reefers than I can count, but have always built them using ELN style driver/power supplies and Apex controllers.

Now I'm looking to dive into using LDD Drivers and Driver Boards, Storm/Storm X controllers and external power supplies. I think I have the correct power supply chosen, but it's best that I ask first before placing my order.

LED's will consist of 7 Strings/Channels as follows:

String 1 - with a total of 38.4vF @ 1000mA (38.4watts)
String 2 - with a total of 38.4vF @ 1000mA (38.4watts)
String 3 - with a total of 38.4vF @ 1000mA (38.4watts)
String 4 - with a total of 38.4vF @ 1000mA (38.4watts)
String 5 - with a total of 38.4vF @ 1000mA (38.4watts)
String 5 - with a total of 19.2vF @ 1000mA (19.2watts)
String 6 - with a total of 29.4vF @ 700mA (20.58 watts)

Total Voltage for LED's = 240.6V
Total Wattage = 231.78 Watts (Which would be the minimum wattage output needed from the power supply)

2 Coralux LDD4 Driver Boards

If I am understanding the LDD drivers correctly, each driver will need 3 volts to operate. This means that I would add the 3v to each string, for total voltage needed to power each string and it's driver (ie String 1, 38.4vF + 3.0V = 41.4v per string).

With the power supply, again if I am correct, the basic rule of thumb is add total amperage for all strings +1A, meaning I need a power supply that will handle 6.7A.

So with all this on paper, I believe that the Meanwell SE 350-48 (48VDC output, 0-7.3A current output). This power supply has 3 DC output connections, each rated at 48v.

Would love to get some input on this to make sure I'm on the right track.

Thanks

[pwreef]

You want to use sealed power supply. It's more money but it does not have a fan that comes on and adds the noise. Meanwell HLG is what I recommend.

[mcgyvr]

yep.. you got it and that power supply should be just fine. (if you don't mind ^^)

[jener8tionx]

I agree with pwreef. I will add that the CLG version may be a bit cheaper. You could also split the load across two power supplies.

[Daimyo68]

Thanks for the replies, I'm glad I have my "logic" correct as to understanding the math on this type of setup.

Now I'll ask, what are the pro's/con's of the HLG/CLG/SE series of drivers?
I do see that the HLG/CLG have better efficiency ratings, but I would think that the active cooling on the SE series of PS's would be a "trade off" for efficiency.

[philnm]

@mcgyvr,

If OP's power supply provides 48 volts, but a string requires 38.4vF + 3.0V = 41.4v, how does it work? Where does the 48 - 41.4 = 6.6 v's go?

This is precisely the issue I'm having right now.

Thanks!

Originally Posted by mcgyvr

yep.. you got it and that power supply should be just fine. (if you don't mind ^^)

[Colin]

Originally Posted by philnm

@mcgyvr,

If OP's power supply provides 48 volts, but a string requires 38.4vF + 3.0V = 41.4v, how does it work? Where does the 48 - 41.4 = 6.6 v's go?

This is precisely the issue I'm having right now.

Thanks!

The drivers take the fixed voltage, variable current of the power supply and convert it to fixed current, variable voltage. It's voodoo.

--Colin

[philnm]

Hehe Colin, I like it ;-)

Do you know if the mechanics of the voodoo the same way if the power supply's voltage is variable and its current is regulated / fixed?

Cheers!

Originally Posted by Colin

The drivers take the fixed voltage, variable current of the power supply and convert it to fixed current, variable voltage. It's voodoo.

--Colin

[Colin]

Originally Posted by philnm

Hehe Colin, I like it ;-)

Do you know if the mechanics of the voodoo the same way if the power supply's voltage is variable and its current is regulated / fixed?

Cheers!

That sounds like one of the old ELN series drivers.

--Colin