Upgrade options for more lumen single cell

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tophat
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Location: Florida
Upgrade options for more lumen single cell

I have a C8 with Xpl hi and a 7135×12 driver. The light is awesome but thought it be interesting to see what else I could do to the same host without with minor changes.

Any ideas or advice to increase lumens? Not substantial but significant enough. I have some new high drain 18650’s that maybe could come into play.

I thought about a Fet driver but.. would that make much a difference? I would think if I used Fet I’d likely need to use a cell thats not rated over 10 amps or so. I have some new 25R and a P26A 35a cell that I suppose would be a bad idea if I kept same emitter. I’m not sure how hard I can push the Xpl hi.

I’m doing some research and schooling myself on forward voltage and so on but it’s going to take a little more studying to fully wrap my head around it all.

I’m basically seeing what’s out there without using a 6v emitter or 3v triples.

BTW, I have a XM L2 as well. Not sure it that would work better.

I had asked this question several months ago but was mixed with another topic so I didn’t really nail down a good direction. Thanks

texas shooter
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There are options for you out there. Your C8 with 12-7135’s is about as bright as that XM L2 is going to get. Take a look at your skill sets and if you’re up to it you can change out the LED for some brighter ones;XP L2, XHP50.2, Samsung LH351D, SST40. intl-outdoor.com is a good source of LED’s. You’ll need to research your driver just too many to list but Convoy is a good place to start. I’m guessing your light uses a 20mm LED MCPCB and a 17mm driver. I’d expect a good max current of 6-8 amps. Take a look at spring bypasses, thicker wires, etc. I wouldn’t do a Fet driver without a thermal sensor.

tophat
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Changing out the led wouldn’t be a problem. I’m running 22awg wires and both springs are bypassed.

So your saying an XP L2 would be brighter than my current XPL Hi using the same 7135×12 driver?

*Edit: I guess it would be a small difference because xp L2 appears to have more forward voltage. The 6-8 amp you mentioned for my particular light would be perfect. I’d definitely have to change something with the driver though. My 7135×12 is rated around 4.5 amp and that’s exactly what I show at the tail with the xpl hi emitter.

Is there any benefit to using a very low IR cell when it comes to using drivers with 7135’s and emitters like Xm L2 or xpl hi? I know there’s less voltage sag but is the higher voltage under load even usable with these LEDs?

Corvette
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The C8 can handle a lot of power, I tried xpl HI, xml2 and others, the real change came with the XHP50.2 3V and a different driver. With a weaker cell and no bypasses, my FET driver works fine. But if I ever decide to bypass all springs and put a stronger cell in, it might be too much current.

So you could change the LED, put in a stronger driver and limit the current with the bypasses or the cell you use.
Lots of options to play with, either way the C8 is a great flashlight.

texas shooter
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The XPL hi V3 is about 10% less output than the XPL L2 hd V6. The XPL also has a higher forward voltage than the XPL L2 that could actually limit your current. Hi amp cells won’t be needed here, go with hi capacity 10-15 amp cells. This Cree table may help a bit https://cree-led.com/support/tools

tophat wrote:
Is there any benefit to using a very low IR cell when it comes to using drivers with 7135’s and emitters like Xm L2 or xpl hi? I know there’s less voltage sag but is the higher voltage under load even usable with these LEDs?

That higher voltage serves a vital purpose, it’s what helps over come all the other resistance. Volts/resistance=current. Save those 35 amp cells for 20 amp lights. 10-15 amp cells are about perfect for 6-8 amp loads, cell has plenty of extra not to be stressed.