I received 30 pcs of XP-G3 S5 2A that I bought from Mouser two weeks ago, and inserted one into Convoy S2 with Fasttech DD-Driver, without bypassed spring. The reflector shows greenish corona with pure white centre (similar to my 5700k Nichia 219B). The tint is just not right somewhere for the corona, very weird colour transition from the centre to the side.
Meanwhile I changed another XP-G3 S5 2A into the DD-drived, bypassed springs SmallSun ZY-T11, it turn bluish and then burned just after a few seconds (battery was LG HE2). I was not able to measure the brightness :cry: The LED eventually became very dim but not fully died.
Next I tried to remove the dome off for the burned LED by finger. The dome was separated from the based with little force. My curiosity led me to try brighten up the dedomed-burned LED, and wow!! It emitted blue~purple light!
What I observed is: the yellow substrate is very similar to MT-G2. Whereby after dedoming by plugging-off using finger, the MT-G2 still light up, and also showing bluish-purple light.
I am still figuring about how can I use them in other flashlights. DD-drive seems not suitable due to its low V, as tested by djozz .
It does not help that you did not use a ‘direct thermal path’ ledboard, the 7 or so ampere that the XP-G3 draws is clearly too much for a non-DTP board, the led overheats because it can’t get rid of the heat fast enough. I suspect on a Sinkpad or Noctigon the led would have been fine.
I tried reflow on a Noctigon 20mm MCPCB again on the small sun with direct drive. At the max mode, it turn cold tint and slowly getting dimmer and dimmer. Now it left 40% brightness of its original. Still colder tint at max, but less brightness. Again, direct drive using LG HE2 still not working for my XP-G3 S5 2A. I have burned 4 out of 5 pcs I tried. Left 25 pcs still in the tape…… :cry:
I am not sure of the tint but i put a XPG3 inside a luckysun D80 @ 5amps and it was okay but it is on a sinkpad from cutter i thought it was a XPG2 but i put the wrong one in! Neewb i know these my first XPG2 and XPG3 LEDs i am working with.
So how is the beam?, I’m pretty curious how this led looks in a reflector light. The Luxeon Q that has the same build with the phosfor around the die has a dinstinct slightly yelowed (but not unpleasant) corona around the more blueish (in comparison) hotspot.
The LED wasn’t DE-domed but the hot spot was tighter then a XML2 it isn’t as bright as the XML2. I will rebuild it and take photos for you soon i can try it in my direct drive C8
For those who want to use that kind of lets with a fet atinny driver: try a max vaule of 200/even 190 in the code, it works fine for me( current tops at 5.7amps)…… even this way XPL is the better option, yes it costs more but who cares for 2-3$ more in the flashlight?
Well, I got two of the XP-G3 from the VOB-Cutter Group buy and one of them is in a cheap 18650 zoomie with a MTN-17DD driver right now. Well, actually, it was a MTN-17DD board, but Dale had built up the driver for me. The XP-G3 was reflowed onto a 16mm Sinkpad, but the pill is hollow, with only a ~1mm or so ledge for the MCPCB to sit on. At first, when I turned it on, the light would start to turn blue as soon as I hit high mode. So I took it out to put a little thermal paste around that ledge. When I did, I saw that the LED wires had got stuck between the MCPCB and the ledge. So, it wasn’t really making contact at all! I got the wires loose, put some thermal paste on the ledge, and put it back together. Oh, I also put just a little of the thermal paste on the threads between the pill and battery tube. Not much, just a dab. Now, it works fine on high. I also removed the spring I had on the driver. It was already bypassed, so it wasn’t offering any resistance, but it held the battery out just a little too much and I couldn’t tighten the tail cap.
The only thing left to do now is bypass the tail spring. Since this is a cheap light, the switch is in a pocket with only a press-fit plastic retainer and no PCB or anything. There is a hollow round brass contact that comes out through the middle of the retainer, and the spring is just laying in there, compressed between the switch contact and the brass battery contact. It’s a very thin gauge steel spring. So, If I solder a wire from the switch to the inside of the brass contact, running through the middle of that spring, I’ll probably see another huge boost in output. If I can learn how to do it right, I guess another thing to do is de-dome the LED. But, I only bought two of these XP-G3, so I want to be careful. I can’t afford to wreck them.
It was very well heatsinked, but the XP-G3 from my test held up fine up to 10A and it looked like it could handle a bit more. So could the problem of the OP also be a not so well mounted ledboard that was not able to shed the heat well enough to the pill??
Yes, my previous heatsink must be inadequate some where causing the XP-G3 to be overheated. This time I have reflowed another XP-G3 onto the Noctigon 20mm and put into a bigger flashlight (SmallSun ZY-T43 with DD-driver). The LED didn’t turn bluish and produce consistent brightness at highest mode.
Compared with the original XP-L V6 1A previously modified, the XP-G3 is only able to achieve ~66% of the brightness under the same setup. Whereby the XP-L V6 produced 83.4 lux of ceiling reflection, but the XP-G3 was only able to produce 55.1 lux; both using fresh 2x LG HG2 in parallel. Finally, I gave up and change back to XP-L V6.
I agree with Mitko, XP-L is a better option. My XP-L HI V3 1A is on the way, hopefully they are real as I bought from TaoBao; the seller is a flashaholic as well :laughing:
Those are interesting numbers, a domed XP-L V6 (that has a bit higher voltage so a lower current in a direct drive situation) has more throw than a XP-G3 S5 !
edit: wait, just noticed that you have 2 high drain cells in parallel, did you measure current? You may have had more than 10A and be well over the maximum output of the XP-G3 (=8A). In that case you could have seen an increase of output during draining of the cells.
My numbers are of ceiling bounds, not throw measurement. It means, the V6 has 30+% lumens than the S5. I did not measure the throw as for the flashlight I used to test XP-G3, it just not “impressive” enough.
edit: You may be right, it may be dropped due to excess current. I didn’t measure the current, and I have changed back to XP-L V6 already :person_facepalming:
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