I built a light today with an XP-G2 on copper being driven with This 3.0A driver.
I don’t really care for the way it ramps, but, the Low-Medium-High setting just gives me Low-High-High. Everything is working fine except for that. Is it the driver, or is it due to the fact that I’m driving an XP-G2 at 3.0A?
i don’t know how to take a tailcap reading, so I don’t really know how hard the emitter is being driven.
Hey let’s not rule out resistance in springs/switches, an uncommonly high Vf for that specific LED (Cree doesn’t bin for them after all), or the battery. Somewhere between the battery sag under a heavy load, resistance, and the Vf of that LED under heavy load I’d bet you aren’t getting anywhere close to 3A. The medium probably is close to driving it at what you get on high.
Tailcap readings aren’t that hard. Set the multimeter to read amps in the range that covers your max expected - 3A. Just connect the probes in series - one to the battery negative terminal and one to the end of the body. You’ll need to switch modes by breaking the circuit briefly; pull the probe off briefly and then make contact again. That will tell the story.
Got maintenance to take a reading at work today. 1.9A on high. I’m going to install a different driver.
And hated it! Try the Q-Lite from Intl-Outdoor, http://intl-outdoor.com/qlite-71358-multiple-modes-circuit-board-304a-p-689.html works beautifully, is quiet, with simple operation. Add a couple of 7135’s if you want even more power but 3.04 should be more than enough for that XP-G2 even on copper.
Edit: What host do you have it in? Might pay to put a copper wire bypass in the spring to get the amperage to the emitter. Sometimes the springs have a lot of resistance, soldering a copper wire or copper wick from top to bottom of the spring gives the electricity a better path.
I'm waiting delivery for the newest Qlite REV.A drivers. I plan to upgrade all the wires and add copper braid to the springs.
I'm using a T10 host from Intl-Outdoor.
Isn’t the Vf for the XPG-2 considered low among the typical LEDS? I feel the issue may lie in the driver. I’ve had a defective one before, maybe they don’t have good QC?
I only picked up the driver because it has a ramping mode. The ramping sucks, and I’ll never use it. It’s a good thing I still have the option of Low-High-High.
If high is only 1,9, then I can understand.
It should be low, high, medium. At least that was the order on mine (4A from IOS). I kinda had the same issue with mine. Not much difference between high and medium. Reason for that is most likely that its hard for the driver to reach high (3a, or 4A in my case). So this makes high and medium look like quite similar… And medium is higher than advertised if I remember correctly.
The driver really likes good batteries with low resistance. Just curious, what batteries are you using?
I have replaced mine with a Qlite with some extra 7135s. My host was T10 too.
If you want ramping. Get a DrJones lumodrv and a flashlight with a side clicky. Awesome combo! 
My favourite driver along with Qlite. I may actually like the lumodrv more… :zipper_mouth_face: And that says a lot!
I’m running Panasonic NCR18650A 3100 unprotected. Sanyo protected were too fat to fit. FT specs say Low-Med-Hi.
I’m not really too crazy about drivers with all these modes that you change by waiting for blinks and such. Nothing fancy schmancy, Hi-Med-Low is good for me.
What emitter are you running in your T10?
I’ve never been able to figure where to go to order a Dr. jones driver. Do you have a link?
Send the Dr. a PM.
I have the "5A" ramping version, I think you're seeing two things. One, the spread between med & high is too small, and two, it won't do the full rated current on high. It likely does do what it's supposed to on medium, which makes the spacing between those modes too small to be visible. It is measurable, though, in tailcap amperage.
I have a XM-L T5 5C on 20mm Sinkpad in my T10.
Like Comfychair said. Contact him by PM.
Info about his drivers here:
http://drjones.dyndns.info/