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Master Valon
03-10-2011, 08:36 PM
Hey guys I just ordered a Deep Red 10W LED from mouser, and wanted to figure out the best way to feed this very hungry beast of an led. The operating voltage is 10.5V, and operating current is 700mA. Now, I was thinking of getting one 8x AAA holder, one 4x AAA holder, and filling them both with NiMHs, to get a voltage of 14.4 V. Paired with a 700mA Buckpuck, this would give it 10.08W. Now, my question is this: do I wire the two holders in series or parallel? And yes I realize the pack is going to be massive, but I have the cramming down to a tee, so I'm good in that department. I just need advice in wiring. Thanks a bunch!

Sunrider
03-10-2011, 09:09 PM
The parallel pcb is the one to get. It can be wired in several ways and run at lower voltages.

It sounds like you got the series pcb.

Tanimal
03-10-2011, 09:12 PM
In series, if you wired them in parallel their amperage would add instead of voltage. But I have to ask, why so many batteries? With that led and those batteries it could run for 20 hours straight!

Master Valon
03-10-2011, 09:28 PM
Sunrider, I'm afraid it's too late for that, as I already ordered the led and it was the series pcb. At $30 a pop, it would be impractical to get the parallel one. Tanimal, thanks- I never quite understood the difference. And the reason for so many batteries is that I wanted to give the led as much wattage as possible. So now, one more question- when I wire the circuit leads to the positive and neg. terminals on the led, it will give all 4 dies 700mA, and thus output maximum lumens, correct?

Skottsaber
03-10-2011, 10:33 PM
It's actually more impractical to use the series one.... as you are finding out.
That many batteries is going to make one heavy hilt.
I'm thinking the best way ti go here would be to use Li-Ion.

Sunrider
03-11-2011, 10:03 AM
700 ma is the low end of the power input. It can run up to 1000ma but would get hot after a while. I would run it about 1000ma and use as much passive cooling as you can. Air cooling can also be done. Run time is going to be tough without being able to use 18650s. I would try to fit 4 14650 li-ions.

Master Valon
03-11-2011, 02:07 PM
Wait, so are you saying I can run it using a 1000mA 'Puck in conjunction with my massive 14.4V pack, or only with the Li-Ion? Because 1.), I don't trust in my abilities enough yet to make a battery pack, and 2.) If I did use the 14.4V/1000mA setup, that equals 14.4 Watts, which I'm pretty sure is well outside the functional range of this led. I wouldn't even want to use 8 alkalines with the 1000mA 'Puck and give it 12 Watts... So barring a custom Li-ion pack, and taking into consideration the fact that I'm stuck with the series led, is this current setup my best bet? And if it is, will it put out close to maximum lumens?

Sunrider
03-11-2011, 02:37 PM
Maximum lumens would be 1000ma at 11v for 15 watts yes. A li ion pack is the only way too keep the pack size under control.

Master Valon
03-11-2011, 04:11 PM
So giving this 10W led around 15W won't kill it?

Sunrider
03-11-2011, 08:21 PM
Right. Don't be suprised when it's not bright though. The deep red is only half as bright as the normal red.

Master Valon
03-11-2011, 09:00 PM
Ok, so I think I'll do this. I'll get the 8x AAA holder, fill them with NiMHs, to get 12V, and drive it with the 1000mA 'Puck to give it a safe but powerful 12W. Anyone tell me if this isn't safe for some reason, because I REALLY don't want to blow this thing out. And Sunrider, I figured anything will be brighter than the 3W Lux. III Green led I have been powering with 4x AAAs and an MR soundboard, and I wanted a really rich, deep color, so I don't think I'll be dissapointed! :)

Edit: Oh, and for heat, I'll coat the heatsink with thermal compound(Arctic Silver 5) that they use in computers, and drill some vent holes in the hilt.

Sunrider
03-11-2011, 10:06 PM
Keep in mind that a buck puck needs 1 volt over vf to work so 12v pack does not give enough overhead. There are boost drivers out there too mind you.




What is a boost driver you ask? http://en.wikipedia.org/wiki/Boost_converter

Master Valon
03-12-2011, 03:14 PM
So would my original 14.4V pack work?

Azmaria Dei
03-12-2011, 03:30 PM
for most of its charge yes. but you won't be able to run a soundboard with it. there aren't any that can take that much voltage.

Master Valon
03-12-2011, 04:53 PM
Yeah, I decided to build a really bright stunt saber with this one. Now, how much run time shall I expect from this build? Like, half an hour, an hour???

Sunrider
03-12-2011, 05:35 PM
Seriously. I would expect a AAA pack to blow up driving a 10w at 12 watts. You really need li ion here. A 12 cell pack is most impractical. 2 18650s could actually handle the current and would have better run time.

Master Valon
03-12-2011, 05:45 PM
But the operating voltage of this led is 10.5V, and wouldn't 2 18650s only provide 7.4V? Could I use 3 AA sized 14500s and a dummy AA in 2 2x AA holders to get 11.1V in conjunction with a 1000mA 'Puck?
Edit: Wait, those are unprotected, nevermind. What do you suggest I do then, seeing as 2 18650s won't get this thing started...

Sunrider
03-12-2011, 06:58 PM
PMed you

PhoenixReborn
03-12-2011, 08:11 PM
You should be able to rewire the deep red in a different configuration. 10.5V is all 4 dies in series. Each die requires 2.625V. I'd just use 2 18650s, and put the LED in series/parallel configuration. 5.25V @ 1400mA for 2 dies at a time.

Sunrider
03-12-2011, 08:37 PM
Yes but he already said he got the serial pcb. ;)

Jedi-Loreen
03-12-2011, 09:12 PM
You should be able to rewire the deep red in a different configuration. 10.5V is all 4 dies in series. Each die requires 2.625V. I'd just use 2 18650s, and put the LED in series/parallel configuration. 5.25V @ 1400mA for 2 dies at a time.
It might be a good idea to read the entire thread before you comment. ;)

Master Valon
03-13-2011, 06:04 PM
Ok, so I just figured out how to power and wire my recently-recieved Deep Red 10W series ledengin led,(Thanks Sunrider!). I just wanted to triple check that this set up will NOT blow the very expensive led. So, my setup is this: a 14.8V Li-ion battery pack(comprised of 4 14650s and a PCB), a recharge port, a 1000mA BuckPuck, a guarded latching SPST switch, and of course, the led. However, this would give this 10W led 14.8W(P=IV). So, just wanted to quadruple check this will safely overdrive the led. Oh, and btw, the operating voltage is 10.5V, and the operating current is 700mA, and maximum Vf is 13.7V, and maximum current is 1000mA. Thanks bunches!:p

Rafalema
03-13-2011, 09:58 PM
I don't think it'll blow. The buckpuck will give the LED-combo as much as voltage it senses is needed.

Skottsaber
03-14-2011, 12:09 AM
Why are you starting a new thread with the same questions?
You'll get the same answers in your first thread.

Jedi-Loreen
03-14-2011, 12:29 AM
I'm merging your 2 threads together.

Master Valon
03-14-2011, 08:23 AM
Sorry mods- got caught up in the heat of the moment of posting! And Raf, by led combo do you mean the four dies?

Master Valon
03-14-2011, 05:57 PM
So I researched buck pucks and forward voltage drops and I only succeeded in confusing myself. Can anyone explain to me how the two are related? On the LEDs data sheet, it said the maximum forward voltage is 13.7V, so wouldn't that mean that with a 1000mA puck, it would receive 13.7W, much exceeding it's rating? Sorry, it's not that I don't trust the information I've recieved from these forums, it's just that it seems counterintuitive to me, and any explanation would be very welcome!

Sunrider
03-14-2011, 06:03 PM
10w is a product name only. If you look at the data sheet you will see 700ma specs and 1000ma specs. LEDs can be under driven as well as over driven. As vf changes so does power consumption when current remains the same. :)

Master Valon
03-14-2011, 06:13 PM
OOOOOOoooooo! Ok, that makes total sense now! So you are saying that power consumption and Vf are inversely proportional when current is constant, therefore I don't need to worry about the led being fed to much wattage as the Vf gets higher? That does make sense... So P=VI doesn't necessarily apply when driving an led with a Puck?

Jedi-Loreen
03-14-2011, 07:25 PM
You really only need to worry about voltage and current, with an LED. Get wattage out of your head.

Master Valon
03-14-2011, 08:01 PM
Mkay I will. So since the maximum current is being hit, and 14.8V is just above 1 V above max. Vf, I'm good?

Sunrider
03-14-2011, 08:45 PM
Vf at 1000ma should be about 11.5 to 12v. it's on the datasheet graph.

Azmaria Dei
03-14-2011, 10:17 PM
i've seen '10W LEDs that are 4 dies running anywhere from 2.9V @ 700mA to 3.4V @ 1000mA. figure that one out. but yeah, just pay attention to current mostly, and voltage second.

Master Valon
03-15-2011, 08:01 AM
Alright sweet. I think Im good then, because the maximum DC current according to the data sheet is 1000mA, and like Sunrider said, max. Vf at 1 A is 12 V, so Im all good!

Master Valon
03-17-2011, 04:33 PM
Hey, new question- for this 10W Deep red LED which im gunna use with a 38" Corbin style blade, do I use the 5 or 10 degree lens?

bk_renesis
03-17-2011, 05:17 PM
I believe the LedEngin 10w works well with the 10 degree lens sold in the store. Some have had success with other lenses but as they are not sold in the store they shall remain unnamed. You will need to use poly wrap or something to to increase evenness across the blade.

Azmaria Dei
03-17-2011, 05:18 PM
i'm using the 5 degree lens in the store and it's very evenly lit across the whole thing. the 10 degree lens had way too much hilt flare for me.

Crystal Chambers
03-17-2011, 05:32 PM
Clear gift wrap will reduce the core effect although a few feet will still leave a nice texture from the corbin film. I've yet to see a red with corbin film I like though. Maybe with the clear wrap but not on it's own yet. I prefer 10 degree but with a 38" blade (that is long) 5 degree is usually recommended. And for corbin blades usually 10 degree. In your case I'm not sure what will work out so it might be a good idea to give yourself a few options in blade film.

Azmaria Dei
03-17-2011, 05:38 PM
oh and i use corbin film in a few (not not my reds) and a foot or two of polypropylene sheeting in the rest.

Master Valon
03-17-2011, 06:05 PM
Ok, I guess I'll use 5 degrees then. What is this polypropylene you speak of? I was just planning to use the double wrap Corbin film... Will that be ok?

Azmaria Dei
03-17-2011, 06:45 PM
like others have said, i don't recommend corbin film with red - it tints the color just a hair and makes it look funny. you know that heavy plastic sheeting that you get things wrapped in now and then? it's a murky white plastic sheeting that's good for wrapping big things in. like crates or palettes. you can also line walls or other things with it. you normally find it in hardware stores in rolls. i picked up the thinnest that i could find of it and it's a hair thicker than construction paper and almost perfectly white.

Jedi-Loreen
03-17-2011, 07:00 PM
Most people use the clear gift wrap that you can find at craft, or some dollar stores.

I haven't heard of anyone using something that you get at a hardware store. I suppose you could use less of that, though.

Azmaria Dei
03-17-2011, 07:07 PM
closest thing i could find and it was cheap. i only need 12-18" of it at most too.

Master Valon
03-17-2011, 07:17 PM
Ok, so I could get this stuff at like a post office or some place, because its used in packaging?

Azmaria Dei
03-17-2011, 07:23 PM
never seen it in a post office... just like hardware stores and stuff. back with all the chain, hose, and sheeting stuff on rolls, normally in the back.

Master Valon
03-17-2011, 07:25 PM
Oh ok cool! Sorry, sometimes it takes me a while! haha

Sunrider
03-17-2011, 08:09 PM
I find it at Hobby Lobby or some place with gift wrapping stuff.

Master Valon
03-18-2011, 07:51 PM
Ok, thanks. So the store is out of the 4 wire 1000mA puck, and since I finally ordered all my parts today, I ordered the 6 wire 1000mA puck instead. Even if I'm not gunna use a pot (as per sunrider's instructions), can I still use this puck and just ignore the extra two wires, or do I have to wire in a pot to complete the circuit? :o

Sunrider
03-18-2011, 09:14 PM
No pot needed.

Master Valon
03-19-2011, 02:31 PM
Cool thanks! So I can either clip those wires or just leave them alone in case I want to eventually use a pot.?

Sunrider
03-19-2011, 03:48 PM
Do what ever you want with them.

Azmaria Dei
03-19-2011, 05:33 PM
you could tie them into a pretty bow ^_^

Master Valon
03-19-2011, 05:39 PM
Haha yea exactly Az! :)

Panzer
04-21-2011, 04:41 AM
Help! Need advise!
1500 mA is not too much for LZ4 Ledengin leds?(red, blue & cool white with custom made huge heat sink)
Should I use 1000 mA buckpuck only?

Sunrider
04-21-2011, 07:57 AM
What does the data sheet say?

Panzer
04-21-2011, 08:33 AM
Says "peak pulsed forward current 1500 mA for red & blue, 2000 for white"
Datasheet here : http://www.ledengin.com/ledengin_products-dataLZ.htm#LZ4
I am afraid my english is not good enough to understand the data correctly.

Sunrider
04-21-2011, 10:48 AM
Says "peak pulsed forward current 1500 mA for red & blue, 2000 for white

A there it is. That is the answer. That is per die in parallel btw.