led driver question

[Diyreef8401]

Led group buy has a ton of information and build ideas. Some good articles to read.

 

[amirk48]

The xp-g3 is definitely more powerful but you will have a hard time finding a small buck driver that will be able to fully realize that power. You would probably need to run an HLG driver they are much larger and much more expensive and use 10 v dimming. A plus is you won’t need a power supply but I still don’t think you want to go that route.

what about this guy here?

BuckBlock DC LED Driver

looks like the mA is enough, not sure about the output voltage
its says " delivers a fixed output current by varying the output voltage as required to maintain the specified current."

 

[Diyreef8401]

what about this guy here?

BuckBlock DC LED Driver

looks like the mA is enough, not sure about the output voltage
its says " delivers a fixed output current by varying the output voltage as required to maintain the specified current."

They are rated up to 32 volts which is fine as you would need 25. If you could find a 30 volt power supply they would work. Also the dimming is 10v so you need to make sure your controller is capable of that.

 

[blasterman]

hi guys thanks for the help!

to give you a better understanding of what im aiming for,
im building a 24" X 24" rimless tank that will have a 12" X 12" hanging fixture over it.
i have five(5) 12" X 1" heatsinks on the way and my plan is to put six 3w leds on each one, which brings me to a total of 30 LEDs.
4 UV
11 royal blue
6 blue
9 cool white

i guess the UV should be on a separate channel since i dont need to dim them,
whites on a dimmiable channel, and blues on a dimmiable channel

i would love to be able to put all the drivers i need inside the the light fixture and just have one cord going from the fixture to the outlet

those buck drivers setups looks exactly like what i need but i have 0 knowledge when it comes leds, could you point me out to what i need to get run the setup i mentioned above?
from taking to LED sellers they recommended on HLG-60H-48B but i wanted to check other options

Dude, seriously. Ditch the juvenile UV and use 2700k warm white LEDs. Actually I would split them 2/2 warm white and red. I'm not kidding. Do this, and you will thank me later.

The ability to dial in some red/orange gives you color flexibility like no other. I do this to all my DIY builds and will never look back.

XPG3s are rated up to two amps. Bucks go up to 1.5amps and luxdrive makes a few bigger. Stick with XPG3s.

 

[oreo54]

what about this guy here?

BuckBlock DC LED Driver

looks like the mA is enough, not sure about the output voltage
its says " delivers a fixed output current by varying the output voltage as required to maintain the specified current."

Well they are fine besides the cost..
If you can settle for less wattage (1500) LDD-L's would work..
Can't use 3.3V but 5V PWM dimming is fine.
$5.49 each

LDD-L Series Mean Well Step-Down Mode CC LED Drivers

 

[amirk48]

Well they are fine besides the cost..
If you can settle for less wattage (1500) LDD-L's would work..
Can't use 3.3V but 5V PWM dimming is fine.

i guess i could settle for 1500mAs, but im trying to stick with solderless and save me the headache of soldering them. but it looks like they only have the loderless ones @ 2000mA

Dude, seriously. Ditch the juvenile UV and use 2700k warm white LEDs. Actually I would split them 2/2 warm white and red. I'm not kidding. Do this, and you will thank me later.

The ability to dial in some red/orange gives you color flexibility like no other. I do this to all my DIY builds and will never look back.

XPG3s are rated up to two amps. Bucks go up to 1.5amps and luxdrive makes a few bigger. Stick with XPG3s.

really? i just based those colors off pics of members tanks here. the light/coral colors of those who had UVs looked really nice and crisp

 

[oreo54]

i guess i could settle for 1500mAs, but im trying to stick with solderless and save me the headache of soldering them. but it looks like they only have the loderless ones @ 2000mA

2000mA is only a suggestion.. you can drive them just fine at 1500mA w/ some loss of light output of course..
Actually the lower the current the easier to cool..
3.06V approx at 2000mA.. 6.12W

Actually 2000mA looks to be max current. RARELY would it be a good idea to run it at that current..430% more output.
from the "test current".

 

[amirk48]

hi guys
tank is cycling and i really need to get the lights going
i gave up the idea of using LDD drivers since they need power supply and controllers and it becomes too expensive..

im planning on (9) 3-up cree xp-e2 royal blue (27 LEDs total)
will this be driver be ok to run these?

Mean Well HLG-60H-48B

.

rapidled.com

obviously ill need 2 of them, but the currant on this one says 1300ma and the XP-E2s are 1000ma
is going going to be a problem? i dont want to fry the leds

id really like to have all 27 royal blues on one dimmable channel if thats possible
is there a driver that can do that?

thanks!

 

[oreo54]

HLG-80H-C700B

84-129v 700mA
HLG-C Series Constant Current LED Driver from Mean Well

https://www.trcelectronics.com/View/Mean-Well/HLG-80H-C700AB.shtml
Max available voltage is 129 good for 37diodes @ 3.4v. 129/3.4


Already solved your problem. What's the issue?


Also showed you the 1050mA driver.

Easily run 27 diodes in series off one of the above drivers (1050 not shown).

Can dim w/ a pot

 

[amirk48]

sorry the other thread had a few conversations going on it was confusing..

how do i choose the correct W for my needs?
27x3=81? is this why you chose the 80W?

is it ok to go with 1050ma if the leds max current is 1000ma? considering they will never work on 100%


thanks

 

[oreo54]

First from a practical sense it is usually never a good idea to drive any LED at their rated maximum current
even if you don't plan on it.
Complicates the design in the sense that it is too easy for "us amateurs" to screw things up heat wise.


Second as you decrease current you do not do it equally. Say you get 50PAR out of the diode at 1000mA
If you use a driver that stops at 500mA it doesn't mean you get 25PAR out of it. It might be 30PAR.
Point is the lower the current, the cooler the diode the more efficient it gets generally speaking.

Don't get hung up on wattage of the driver.. It's a sliding scale so to speak.

What IS important is their maximum/minimum voltage out they are capable and the current set point.
Take this chart of the xpe2 as an example:

IF you fed the diode EXACTLY 3.4V it would draw 1050mA from the power supply.
Conversely if you allowed 1050mA out the driver it would need to raise the voltage to 3.4V
One would say the V(f) at 1050mA is 3.4V

Constant current drivers control the current by changing the average voltage (normally) the diode gets.


The 3.4V number determines how many diodes in series a driver can handle before not being able to output the
right amount of current.

So in your case 27 (though thought you stated 30 earlier) at 700mA you need about 3.25 x 27 = 87.75V
87.75 x .7A = 61.425W

at 1050 drive current
3.4 x 27 = 91.8V
91.8 x = 96.39 Watts out.

Like I said as long as the driver fits your necessary voltage determined by the current you want to run them at (based on the SPECs of the diodes and your confidence in cooling them) it doesn't matter what it calls itself.
Your array will be in the design specs of the driver..

Which one you choose is almost arbitrary.

Say you go with the 700mA driver but find you are under powered a bit.. as long as you got voltage to spare you just add more diodes

Say you have the exact same amount of wattage between 2 sets, one driven at 1050mA another at 700mA
The 1050 has x amount of diodes, the 700 has x+y amount of diodes.. again assume the (diodes x.7) and the (diodes x 1.05) is equal wattage.

You will normally get more photons out of the 700mA set due to having better efficiency at the lower current.

LAST thing though.. The lower limit is also important but not likely in your case.
Say the lower limit is 60V and the upper limit is 100V and is set for 1000mA current.
Your diode reaches 1000mA at 3.4Volts.
You need more than 17 diodes ( 18 x 3.4V =61.2V) but not more than 29 (29 x 3.4 =98.6V) to keep within specs of the driver.

Now you should see why this was wrong:

Mean Well HLG-60H-48B

.

rapidled.com

Never enough voltage.
48v tops.. and even if you had the right number of diodes the amperage was out of spec for it.
You could probably run and burn out 13 (or extremely shorten their lifespan) of them..

 

[stefanm]

sorry the other thread had a few conversations going on it was confusing..

how do i choose the correct W for my needs?
27x3=81? is this why you chose the 80W?

is it ok to go with 1050ma if the leds max current is 1000ma? considering they will never work on 100%


thanks

Where are you based, in the US or another country? It may help a little.

 

[amirk48]

First from a practical sense it is usually never a good idea to drive any LED at their rated maximum current
even if you don't plan on it.
Complicates the design in the sense that it is too easy for "us amateurs" to screw things up heat wise.


Second as you decrease current you do not do it equally. Say you get 50PAR out of the diode at 1000mA
If you use a driver that stops at 500mA it doesn't mean you get 25PAR out of it. It might be 30PAR.
Point is the lower the current, the cooler the diode the more efficient it gets generally speaking.

Don't get hung up on wattage of the driver.. It's a sliding scale so to speak.

What IS important is their maximum/minimum voltage out they are capable and the current set point.
Take this chart of the xpe2 as an example:

IF you fed the diode EXACTLY 3.4V it would draw 1050mA from the power supply.
Conversely if you allowed 1050mA out the driver it would need to raise the voltage to 3.4V
One would say the V(f) at 1050mA is 3.4V

Constant current drivers control the current by changing the average voltage (normally) the diode gets.


The 3.4V number determines how many diodes in series a driver can handle before not being able to output the
right amount of current.

So in your case 27 (though thought you stated 30 earlier) at 700mA you need about 3.25 x 27 = 87.75V
87.75 x .7A = 61.425W

at 1050 drive current
3.4 x 27 = 91.8V
91.8 x = 96.39 Watts out.

Like I said as long as the driver fits your necessary voltage determined by the current you want to run them at (based on the SPECs of the diodes and your confidence in cooling them) it doesn't matter what it calls itself.
Your array will be in the design specs of the driver..

Which one you choose is almost arbitrary.

Say you go with the 700mA driver but find you are under powered a bit.. as long as you got voltage to spare you just add more diodes

Say you have the exact same amount of wattage between 2 sets, one driven at 1050mA another at 700mA
The 1050 has x amount of diodes, the 700 has x+y amount of diodes.. again assume the (diodes x.7) and the (diodes x 1.05) is equal wattage.

You will normally get more photons out of the 700mA set due to having better efficiency at the lower current.

LAST thing though.. The lower limit is also important but not likely in your case.
Say the lower limit is 60V and the upper limit is 100V and is set for 1000mA current.
Your diode reaches 1000mA at 3.4Volts.
You need more than 17 diodes ( 18 x 3.4V =61.2V) but not more than 29 (29 x 3.4 =98.6V) to keep within specs of the driver.

Now you should see why this was wrong:

Mean Well HLG-60H-48B

.

rapidled.com

Never enough voltage.
48v tops.. and even if you had the right number of diodes the amperage was out of spec for it.
You could probably run and burn out 13 (or extremely shorten their lifespan) of them..

wow thanks for the detailed answer!! i have a much better understanding now

one more question, does LEDs always have to be wired in series? im asking because if one LED is burnt it will shut down the whole channel is that right?

 

[amirk48]

Where are you based, in the US or another country? It may help a little.

im in the US

 

[oreo54]

wow thanks for the detailed answer!! i have a much better understanding now

one more question, does LEDs always have to be wired in series? im asking because if one LED is burnt it will shut down the whole channel is that right?

simple questions rarely have simple answers...
Technically no the diodes don't always need to be all in series.
Many led "things" are composed of series/parallel arrays.
With high power leds there are some issues to be aware of and it's generally not done in DIY..

There are methods of dealing with the one diode fails open issue. Some LED's have built in shunts in the event of failure.
One can add those as well.
There also are chip packages that deal w/ it.
Sort of based on things like this:
https://patents.google.com/patent/US8410705B2/en

Best thing to remember about series/parallel is current divides in parallel.

So say you have 2 equal strings and use a 2000mA driver (to get 1000mA to each series string)
IF one of the 2 strings fails "open" ALL 2000mA is now directed at the one remaining string.
Possibly damaging or burning it out .

People that do things like this generally add, at the least fuses on the end of the strings.
Say a 1.5A fuse on each series string so it blows and saves the remaining string.
Blown line is good.. un-blown has the issue.

Of course if you go series parallel say 10 diodes/3 strings your driver voltage/current calculations change.
3.4 x 10 =at least 34V needed and a 3A driver
Each leg gets 1A
34W x 3 =102W

30 in series on a 1A driver.
30 x 3.4 x 1 = 102W

 

[amirk48]

yeah that doesn't really go with my "keeping is simple" approach..
i'm better off just keeping a replacement led on hand

ill put the parts order in and will probably hit you up with some more wiring questions soon lol
thanks again!

 

[amirk48]

hi,
so im trying to put an order in through LEDsupply but seems like the only one they have in stock is the HLG-120H-C1050B.
will i be ok getting this one and running it lower with a pot or is it too risky?

 

[oreo54]

hi,
so im trying to put an order in through LEDsupply but seems like the only one they have in stock is the HLG-120H-C1050B.
will i be ok getting this one and running it lower with a pot or is it too risky?

I have only one thing to say.. I don't build to save money. If I do great if I I don't, as long as it's not crazy bad.. ehh...can always recycle all of it.

HLG-80H-C700AB - MEAN WELL - TRC Electronics

Order MEAN WELL HLG-80H-C700AB LED power supply on-line or call today for exceptional customer service. TRC is the USA stocking headquarters of MEAN WELL HLG-80H-C700AB LED power supplies. HLG-80H-C700AB is ready to ship today.

www.trcelectronics.com

So I'd go w/ this.
Oh oddly cart doesn't work in firefox so use windows junk.
My choice.

Oh and the fact that they are hard to get.. makes me want them even more..

 

[oreo54]

One odd thing . Minimum voltage is either 64 or 84v. At 84 v you sort of reach the 27 diode minimum.
So keep that in mind.
If you go 700 mA best to stick w/ 30 diodes.

The ab types are really always preferred ..to me.
I thought years ago it was silly choosing between dimming or current adjustment.

 

[blasterman]

The more LED's you run in series the higher the forward voltage is and the more chance at shorts, solder breaks, thermal inrush and other issues. This is how you increase the chance of burning out LEDs.

Multiple Parallel runs help keep the voltage low. While you have the issue of possible parallel leg failover sending too much current to the working legs just don't design it that way and leave yourself some breathing room. If one leg fails and sends all the current to 2 or 3 other legs there should be enough current head room so those legs can handle it for awhile. This is the biggest reason you don't drive LEDs at max.

High voltage + DC + DIY = bad. 50volts of Cree XPG3s in a single series driven hard will knock you on your butt before the driver cuts it off. Been there - done that. Those 50volts of LED distributed across several parallel legs of ~18 volts are much safer and will yield less chance of solder jumps and shorts. MeanWell has any possible voltage and current combination of driver out there, so that part is a non issue.