F-Series Gen 3 DIY

glimm

Member
Hello riu,

I have been eyeing the LT-FB24B strips for my first build. My goal is a "minimalist" ~600W fixture that is focused on efficiency.

So while price is sort of an issue, I really want to drive that beast as low current as possible. Now, in the F-Series Data Sheet : Vf = [43.7 to 48.4] V and If,typ = 2240 mA.

So my question is the following : how low can they be driven in practice?

Also, what would be the safest way to wire them? So that even if one strip fries, the fixture remains cool, calm and collected.

So, 6, 7, 8, 9 or 10 of these strips? No half measures here. And which driver for the job?
 

glimm

Member
Thanks guys.

3 drivers sound like more parts and more work. I looked up the HLG-600H-48A (HLG-600H-54A also), you think they would be efficient at all in lighting up the LT-FB24B strips?

Also, how many could it handle?

Help me out LED wizards bongsmilie
 

nc208

Well-Known Member
65 ma per diode up to 200 ma per diode is how hard you can drive them. How big a space are you lighting?
 

glimm

Member
Basically a 4' x 4'. One room, one lamp.

What I've gathered so far is that I should wire them in parallel in an equidistant manner. I like the idea of having 1 bigger driver. Which of the 2 drivers I mentionned would be preferable for my setup?
 

nc208

Well-Known Member
Basically a 4' x 4'. One room, one lamp.

What I've gathered so far is that I should wire them in parallel in an equidistant manner. I like the idea of having 1 bigger driver. Which of the 2 drivers I mentionned would be preferable for my setup?
LT-FB24B : 16S x 18P
first aim for how hard you want to drive them. I'm running mine at 116.67ma per diode which according to calculator is around 180lm/w. So 116.67*18= 2100.6 so each strip would need 2100ma to drive them that hard with each strip needing 46v. This driver HLG-480H-48A will handle roughly 5 strips at just under the 116.67ma current. the 600h 54a can only handle an extra 1.2 amps than the 480h so not worth the extra money. 2 x the hlg 480h-48a will suit your needs for up to 10 strips.
 

glimm

Member
Correct me if I'm wrong. You said 65 mA per diode up to 200. Sticking with the 600H-48A, we get Rated Current = 12.5A. 12.5A/9 strips = 1388.89 mA. Or 77.16 mA per diode.

With 8 strips we get 1562.5 mA per strip or 86.81 mA per diode. Why would 2 drivers be better? I'm not trying to overshoot 600W at all. It's my max.
 

nc208

Well-Known Member
Correct me if I'm wrong. You said 65 mA per diode up to 200. Sticking with the 600H-48A, we get Rated Current = 12.5A. 12.5A/9 strips = 1388.89 mA. Or 77.16 mA per diode.

With 8 strips we get 1562.5 mA per strip or 86.81 mA per diode. Why would 2 drivers be better? I'm not trying to overshoot 600W at all. It's my max.
no you aren't understanding, each strip is designed in a 16 series with 18 parallel connection, that means whatever you supply each strip with has to be divided by 18 to see how much each series string will receive. As I wrote earlier each strip will need 2100ma to be run at 116.66667 ma per diode. so if your driver can handle 12.5a then it could technically light up 6 strips at 2083ma each.
 

glimm

Member
The math I posted is exactly what you just said bongsmilie

I wanna drive the strips with even less current than that. Would 8 strips turn on when driven by the aforementioned driver (HLG-600H-48A)?

If you took the time to read the OP, I stated I want the fixture to run cool even if 1 strip burned out. Which is why I want to underdrive them.
 

paraordnance

Well-Known Member
I honestly don't understand why you want them run really soft they not a COBs that overheat quickly. F series can take some beating. I'm running my fb-24b (4') in pairs with hlg-240h-48b and at 2.5 A per strip they barely produce any heat. Aluminum U channel only gets to about 50C with zero cooling. You can always dim
 

Prawn Connery

Well-Known Member
^ This. How much more "efficiency" are you gaining anyway? Looking at the data sheet, there's only a very small percentage difference in relative terms between 65ma and 130ma.

I've got an almost identical set-up to paraordnance (4x 2' strips instead of 2x 4' with a HLG-240H-48A)). I run my F Strips at about 65% and my U channel is warm to the touch with no active cooling. I dialed them down to about 35% to strike some clones, and the light was so weak and the temperature so low, the clones struggled.

As far as I can see, the main advantage to running strips so low is to extend their life. But I'll replace mine in a couple of years when something better comes along anyway.
 

glimm

Member
@Prawn Yeah the life expectancy isn't why I'd consider driving them this low. I want the fixture to be safe to operate even if 1 of the strip were to burn. So from there, while 7 strips (~85.7W ea) sounds really good, I can't figure out a way to wire them so that they're exactly equidistant. But with 8 that's simple. Two 5 ways WAGOs. I'd definitely consider 6 too but I need to see the hard math.

In fact that's the next part I'll be looking into, circuitry. Paint job incoming :bigjoint:

About the heat, that's not an issue I'll just turn up the radiators. If you're building a lamp, wouldn't you want the less amount of heat possible to produce more photons?

Now is 75W even gonna power those bad boys?
 
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paraordnance

Well-Known Member
@Prawn Yeah the life expectancy isn't why I'd consider driving them this low. I want the fixture to be safe to operate even if 1 of the strip were to burn. So from there, while 7 strips (~85.7W ea) sounds really good, I can't figure out a way to wire them so that they're exactly equidistant. But with 8 that's simple. Two 5 ways WAGOs. I'd definitely consider 6 too but I need to see the hard math.

In fact that's the next part I'll be looking into, circuitry. Paint job incoming :bigjoint:

About the heat, that's not an issue I'll just turn up the radiators. If you're building a lamp, wouldn't you want the less amount of heat possible to produce more photons?

Now is 75W even gonna power those bad boys?
Exactly equidistant? Do you realize electrons move within wires at the speed of light. So what is equidistant in your mind? Wires that differ in length by 0.0001 of an inch are not equidistant. I'm not even sure what are you trying to accomplish here. You got some flawed concepts here I think and you trying to follow through them no matter what.

With 2 strips in parallel like I'm running from HLG-240H-48B they draw 2.5 A per strip, or 5 A total per driver. At 2.5 A and 47v per strip I get roughly 117 watt per strip, or as confirmed by a meter 250w from the wall from both strips. At 70w (max) per strip as you planning to use they will be dim, dim, dim oh so dim and you will have to keep them just a few inches away. You going to regret your underpowered set up once it's built.
 

MajorAce

Well-Known Member
2-2x4 fixtures
3-fb24b each fixture
2-HLG-320-48
Easy wiring and and easier hanging.
If you lose a strip the other two are still under max at 186ma per diode.
 

Randomblame

Well-Known Member
You can drive a few strips hard or many strips low, it makes no difference, as long as you produce the same amount of light, you can also operate the strips more efficiently.
Samsung H-strips for instance run with 80mA per diode and you get 180lm / w(3000°k), at 124mA (F-strips nominal current) you get 168lm / w and with 116mA is should be ~ 170lm / w( @nc208 ).
LM561c is binned and tested at 65mA, can run with up to 200mA but can also be driven at 40mA if you want. You just need more diodes to compensate that.
The 3k-diodes in my next build only gets 60mA (198lm / w), but I'll use 24 2ft. F-strips or 1728 diodes (equiv. 6 QB's) for a 250w light. But I am very limited in height and must be able to hang it as close as possible above the canopy(4-8").
But that does not mean that it is not effective farther away!!!
250w are 250w and in fact my lamp will even produce more light because it's more efficient as a lamp with only half as much diodes driven at 120mA.
The more diodes you use the more diffuse is the light and diffuse light is the light that reaches deep into the canopy, not intense light. Intense light from above(point source) is quickly reflected from the upper leaves, through the leaves penetrates only a little green light. Light from hundreds of different angles, can penetrate much deeper, because there are always a few rays that go unreflected into deeper zones.
In my opinion, you are on the right path.
Efficiency is expensive, but it maximizes usability and your per-watt yields!
 

VegasWinner

Well-Known Member
The math I posted is exactly what you just said bongsmilie

I wanna drive the strips with even less current than that. Would 8 strips turn on when driven by the aforementioned driver (HLG-600H-48A)?

If you took the time to read the OP, I stated I want the fixture to run cool even if 1 strip burned out. Which is why I want to underdrive them.
Smart move best drive current is 88ma for highest output
 

VegasWinner

Well-Known Member
I drive LM561C diodes as close to 88ma as possible. It is not about heat loss but output of 200lm/w. Plants respond well to the light level even during flower period. Driving harder appears to the eye as brighter but you are growing plants not eyes.
Softer is better. Your choice of 8 strips works great
 

Randomblame

Well-Known Member
I drive LM561C diodes as close to 88ma as possible. It is not about heat loss but output of 200lm/w. Plants respond well to the light level even during flower period. Driving harder appears to the eye as brighter but you are growing plants not eyes.
Softer is better. Your choice of 8 strips works great

I'm reluctant to destroy your dreams, but with 88mA also a 5000°k LM561c diode did not reach 200lm/w.
Screenshot_20171216-212738.png
 
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