Brightness: LedEngin 10W vs. Seoul P4

[DizzyKungFu]

OK all you LED experts, I think I'm doing something wrong here, so I hope someone can straighten me out.

I recently purchased an LedEngin 10W GGGG. So I wired it up in one hilt (all 4 dies in series), and put it next to a green Seoul P4 in another hilt. They look pretty much the same to me!!! Or at least, a mouse could starve off the difference!!! After all the raving about the LedEngins (not to mention the company's own lumen specs) I figured the difference would be profound. I can only assume that I've somehow screwed it up.

Here are the setups:

P4: 2 freshly charged TrustFire 14500s (7.4 V), 1000mA BuckPuck, green P4, 10° optic, 36" dual-wrap Corbin battle blade.

LedEngin: 4 freshly charged TrustFire 14500s (14.8 V), 1000mA BuckPuck, GGGG 10W LedEngin (individual die model, wired in series), 10° optic, 36" dual-wrap Corbin battle blade.

Thoughts? Can anyone spot where I went wrong? Thanks!

[Rhyen Skytracker]

Try wiring the GGGG in series parallel. Wire 2 in series and 2 more in series and put both of the series circuits in parallel. Using a buck puck may be starving the LEDs of some of the voltage. Using the series parallel circuits you should get plenty of voltage to the LEDs but it will cut down on the run time a bit. But it should be brighter this way.

[DizzyKungFu]

Huh. So GG and GG? Will I need a BuckPuck for each parallel circuit, or split it after the puck? From my understanding (correct me if I'm wrong), spliting it after puck will half the amperage.

[Arkhan]

If you have the 6-wire 1000ma buckpuck, you can double up on the input voltage and get two separate 1000ma circuit (if I understand them correctly).

output circuit 1 powers 2 green dice wired in series.
output circuit 2 powers 2 green dice wired in series.

1 and 2 are in parallel with each other.

You get 2000 ma worth of LED goodness, at the cost of battery life.

If you have the 4-wire buckpuck, I'm not sure you can do this.


Those with more buckpuck experience, please chime in.

[DizzyKungFu]

I suppose I could go simple resistor here, if the BuckPuck is part of the problem. It's not REALLY required... while nice to have, I'd much rather have this famous brightness.

[Rhyen Skytracker]

I would use resistors and slightly overdrive them to get the max out of it.

[FenderBender]

Also, depending on the actual binning of the particular 10W, you may not have enough vf to power it completely. I had a 10W amber that needed 14.8 to run when most of the specs say it should run on 10v. Some of the green 10W's can need up to 18V to run properly. I just did a RGGB with the two G's wired in series and it was brighter than a P4 overdriven and even a Lux V. Also, what optics were you using? Another thing is that ALL LEDengins are current hogs and aren't really happy unless they're running at 1.5A.

[DizzyKungFu]

Also, what optics were you using?

The standard TCSS Lux 10° optics on both setups.

Another thing is that ALL LEDengins are current hogs and aren't really happy unless they're running at 1.5A.

Hrmmm... the specs also say that they should be run on 700-1000mA, so that's a big departure! If you're right about the specs being off, that could be part of the problem.

Would it be worthwhile to rewire the series to just use 3 dies? I'm certainly not getting much out of 4, but if those other 3 could each be brighter, it would probably be better overall. Perhaps?

[FenderBender]

Try it. Can't hurt. My bet is that you got a high power bin LED and it's wanting closer to 17/18V to be at maximum. 14.8 is probably just turning it on. Yeah, 1500 is LEDengin's max current rating on all their LEDs from 5W up. 1000 is typical.

[Sunrider]

Fender is right. I you watch the voltage it will drop pretty good under load. 4 14500s are not enough to drive the 10w for more than a few minutes.