Matching Drivers and COBs

so ill give you 8% (optimistic)
lets crank some efficiency numbers:

avg CD at 12500: 50W = 56%
avg DB at 13500: 50W = 60.7%
avg DB at 13500: 65W = 56%

to get to 75W from 50 at the same efficiency youd need about a 13% bump. so thats like early DD chips.. not impossible but prob a year out

ttystikk said:

It will cost less too, since I'm buying half the number of drivers.

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for a given number of lumens maybe a 10% reduction in driver cost year over year at this point

BOBBY_G said:

for a given number of lumens maybe a 10% reduction in driver cost year over year at this point

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...except that the new design means I'm using half the number of drivers, so this part of the math is easy, lol

BOBBY_G said:

so ill give you 8% (optimistic)
lets crank some efficiency numbers:

avg CD at 12500: 50W = 56%
avg DB at 13500: 50W = 60.7%
avg DB at 13500: 65W = 56%

to get to 75W from 50 at the same efficiency youd need about a 13% bump. so thats like early DD chips.. not impossible but prob a year out

Click to expand...

Yer fuckin' brilliant, you know that? Seriously, you answer the questions I'm not sure I had formed well enough to ask.

So can you do the 75W case? I'm guessing the efficiency loss is pretty small?

I do believe that Cree does not service a new bin unless the whole bin jump is reflected, I remember someone saying that's how it worked, specifically to avoid the criticism of hyping less than full bin gains.

If I can get close to my current 56% efficiency while running higher bin chips at 75W I'll be extremely happy. It's more heat but that plays to my strengths, doesn't it?

ttystikk said:

...except that the new design means I'm using half the number of drivers, so this part of the math is easy, lol

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sort of.... if you look at the driver selection tables, they are based on $ per watt, and they bottom out around 0.30/W regardless which size driver you select. best you can do in this cas eis make sure the drivers are sized to where you are dimming as little as possible. dim to half power, your driver cost per watt just doubled.

ttystikk said:

Yer fuckin' brilliant, you know that? Seriously, you answer the questions I'm not sure I had formed well enough to ask.

So can you do the 75W case? I'm guessing the efficiency loss is pretty small?

I do believe that Cree does not service a new bin unless the whole bin jump is reflected, I remember someone saying that's how it worked, specifically to avoid the criticism of hyping less than full bin gains.

If I can get close to my current 56% efficiency while running higher bin chips at 75W I'll be extremely happy. It's more heat but that plays to my strengths, doesn't it?

Click to expand...

again when they sell you DB, they are out of the DB "bin" they are guaranteed 13000 lumens at 85C. still mfr'd a bunch of CD bins along with those, and sold em to someone else.

not sure what you mean by 75W case, maybe like this

avg CD at 12500: 75W = 49.6% (my current "entry level" poverty efficiency til i afford more cobs)
avg DB at 13500: 75W = 53.6%
avg CD at 12500: 59W = 53.6%

BOBBY_G said:

sort of.... if you look at the driver selection tables, they are based on $ per watt, and they bottom out around 0.30/W regardless which size driver you select. best you can do in this cas eis make sure the drivers are sized to where you are dimming as little as possible. dim to half power, your driver cost per watt just doubled.

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Hmmmmm, educational as always.

What's this thing you speak of, called 'dimming'?

its like trimming except your hands dont feel like rusty shears in the morning

you know whats gonna be better than commonly available DD chips next year?

.....$30 commonly available DD chips!

ttystikk said:

On what?

STRAIGHT FROM CREE TODAY:
DB BIN 4000K CXB3590 are available now
DB BIN 3500K CXB3590 have no part number assigned as yet. Once they do, a prepaid order will be filled in about 5 weeks or less.

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I'd love to see 3000K 90CRI CB.

I'm running 4 CXB 3070's off of one HLG-185H-C1400. It is rated at "4" CXB's, so that is apparently optimal efficiency-wise.

I'm also running two pairs of CXA 3070's on separate switches and separate drivers. There does not appear to be a driver that has a rating of running "2" optimally, so I went with HLG-120H-C1400, which can run "2.9" CXAs.

The bottom line, the drivers running the CXA's are running cool as can be, and the one driving the 4 CXBs apparently more efficiently, is hot... hot enough that I can only keep my hand on it for about 5 seconds before its seriously uncomfortable.

Out of curiosity, if I had gotten the HLG-185H-C1050, rated at "5.5" CXBs, would it run cooler because it was not running at its limit?

And if I've totally misunderstood how this all works, thanks in advance for you patience and kindness. I'm just doing my best to follow the charts...

well in your setup each driver running 2 cobs puts out about half as much heat as the single driver pushing 4.

so the one running 4 cobs should feel warmer

BOBBY_G said:

well in your setup each driver running 2 cobs puts out about half as much heat as the single driver pushing 4.

so the one running 4 cobs should feel warmer

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Thanks for the reply.

So you are saying that if I ran an HLG-185H-C700 which can run 8.5 CXB-3070s, and I ran 4 COBs with it, it would still run hot? The heat has nothing to do with the driver running at near its maximum?

So i have decided to build a light set up. I plan on running (3) 4.23 x 30" heat sinks with (3) CXB 3590 CD 36V 3500's cob's on each HS, want to do this right, so, question. Which drivers should I use and should they be "C" or "B" version. want the best drivers, so should I run 3 of them, what size ?

nl5xsk1 said:

So i have decided to build a light set up. I plan on running (3) 4.23 x 30" heat sinks with (3) CXB 3590 CD 36V 3500's cob's on each HS, want to do this right, so, question. Which drivers should I use and should they be "C" or "B" version. want the best drivers, so should I run 3 of them, what size ?

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Is that going in a 3'x3' tent? Sounds perfect if it is. You could use the HLG-120H-C1400B for each 3 cobs which would be dimmable. At full power it would give about 50w per sqft.

Danielson999 said:

Is that going in a 3'x3' tent? Sounds perfect if it is. You could use the HLG-120H-C1400B for each 3 cobs which would be dimmable. At full power it would give about 50w per sqft.

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Whoa, that was quick, and yes , that is my area, and I have been reading Captainmorgan thread, but I think he is using 9 800 ma drivers.
So if i go with the 3 you suggest ,then I need a potentiometer and a resister for dimming?

So would I need a 150K pot and what size resister

ttystikk said:

Yer fuckin' brilliant, you know that? Seriously, you answer the questions I'm not sure I had formed well enough to ask.

So can you do the 75W case? I'm guessing the efficiency loss is pretty small?

I do believe that Cree does not service a new bin unless the whole bin jump is reflected, I remember someone saying that's how it worked, specifically to avoid the criticism of hyping less than full bin gains.

If I can get close to my current 56% efficiency while running higher bin chips at 75W I'll be extremely happy. It's more heat but that plays to my strengths, doesn't it?

Click to expand...

No sh**, right?? Man.. Bet it was off the top of his head too. I understood about 65% of that.. I'm proud! Lol

nl5xsk1 said:

So i have decided to build a light set up. I plan on running (3) 4.23 x 30" heat sinks with (3) CXB 3590 CD 36V 3500's cob's on each HS, want to do this right, so, question. Which drivers should I use and should they be "C" or "B" version. want the best drivers, so should I run 3 of them, what size ?

Click to expand...

Can't run passively

And if you plan on wiring all 3 drivers together on ONE single plug, you needba 33-35k Potentiometer.