Direct Drive MT-G2 with Two Samsung 20R's

My Shadow tc300 (a modest size light) modded direct drive with a MT-G2 does 8 amps (initially) on two cgr18500ch's for a few minutes of wow, and for prolonged use I can put two A123 18650 LiFePo 's in it for 2A and 1100 otf lumens.

How is the heat in that one djozz? Is there a line there somewhere in the middle where the choice between XM-L/XM-L2 crosses what the MT-G2 is doing? I put an XM-L U3 in a SupFire F9, driving it at 4.41A with Sanyo lap pulls for 1259 lumens OTF at 30 sec.

Makes me wonder at what point the 2 footprints cross over in lumens, amps and heat. Where’s the happy medium?

I’ve also got an XP-G2 in my Convoy C8 pulling 4.55A on a Samsung 20R and making 883 lumens OTF. Tighter beam yet again over the XM-L footprint.

It’d be cool to find out where the heat was the same for the 3 sizes, at what amps and then what the output was by comparison. If heat were the determining factor, say 125ºF at 5 minutes on the plane of the emitter on the head. Wonder how that would end up? Might be a surprise to a lot of us!

EDIT: I might just try that. Convoy C8’s in a host only are about $10. So 3 of those would be about the cost of a semi-normal light. With an XP-G2, XM-L2 and MT-G2 I wonder what the magic amp number would be to create 125ºF at a given place on the head in 5 minutes? It’d be an easy thing then to compare beam profiles and lumen output, as well as kcd and throw range. Hmmmmmm……

Direct drive seems to be a common way to drive the MT-G2, if you want some serious output. Has anyone else used a buck driver with 3 or 4 cells besides MRsDNF to regulate current? I’am not really crazy about the idea of running 3 or 4 cells in series, pushing 6 amps or more through each cell. One lazy cell could spell disaster with that much current. Looking for ideas before I go and spend several hours machining a solution. 2 cells and a voltage modified amc7135 driver with modes seems might be my best option, but I wouldn’t mind running the MT-G2 at 8 or 9 amps fully regulated either.

007, it seems like 7A is the best middle ground. For the amperage required, the heat produced (and dealt with) and output…the heat produced and likewise expense gone to in order to deal with it is really more than the output is worth after 7.

And, well, it does seem like 7 is your “lucky number” :wink:

I completely understand what your saying DBCstm, I just cant help myself. I keep looking at that wonderful graph djozz provided and wondering how to achieve near the top of that mountain. :~
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Does anyone know of another source for the IOS 9 amp driver?

Interesting, looks like that graph at 12A match's Dale's results exactly! 12A - 4,140 lumens... The graph looks like ~ 4,160 lumens - damn close.

Half a blink and you’d miss that 4140! The cell was losing fast at 12, REAL fast!

the IOS driver was not successful in this application in the respect that it would lock into high after a short period of time and would not change modes.

You beat me to it. The same thing happened to me.

So far the lustefire triple driver has been the best for me.

@18sixfifty
Whats the numbers look like with a single MT-G2 and battery configuration?

I’m running it in a ZY-T08 and I’m getting around 3,000 lumens at startup and 2,800 steady after that with unprotected sanyo’s. This will pop the protection on Panasonic 3400’s after about 30 seconds. It’s more lumens on startup with samsung 20r’s but I don’t remember exactly how much.

I couldn’t tell you how many amps but you might be able to guess considering that it pops the protection on two pretty good cells. I think it was comfy who ran this same driver to power a 3xMT-G2 and he was getting about 3amps per emitter with three cells.

I e-mailed both wallbuys and fast tech to see if they would put this driver in stock. They both said they would but neither of them have and it was a while back. It can be trimmed down some to fit the XY-T08 but not much if any more than that. 29mm

I have also used the original 3xT6 and the driver from a J-18 and both worked well and can be modded to put out more if you wanted to. I have a link someplace that sells them. I’ll try and find it. It’s in Spanish I believe.

Fasttech sells a 3xT6 copy, it was what I original tried at the beginning of this thread along with the pot mod. Maybe I’am trying to reach too high on that mountain. I’ll keep looking and testing. Maybe I can find a happy medium some where.
Thanks for the info 18sixfifty. :wink:

I use This driver in a 4D maglite with 4 26650 cells. No problem so far.

If anyone here is using a driver and don’t know about this thread, it may be helpful.

You’re welcome and let me know if you have any luck. I really want to put together a 3x again. I did it once with the IO in fact I tried three different IO drivers and they all had the same thing happen they froze up. Apparently they do the same even if running one.

I couldn’t find the link for the J-18 driver but the number on it is TR-0169D

I knew Taskled would be tried at some point. I doubt you ever will have a problem either. I know that’s is about as good as it gets besides maybe cpf member Der Wichtel’s driver original for the SST-90. I’am not really looking to spend that much on the driver alone. I would like to find a budget driver to get the job done. I appreciate your response, Taskled drivers are some of the best made.

I’ve had two of these drivers for a couple of weeks but not game to try them as I will probably blow them up. I’ve cried enough this year. Its bad enough blowing a $20.00 led up.

I’ll be more than happy to blow em up for you! :slight_smile:

MRsDNF, by all means blow ’em up! But please get it on film!
I saw this light and thought it would make a useful host for an MTG2 I plan on running at 5 amps. Willbuying 2x18650 XML light Anyone play with one of these yet?

I would prefer something that looks like a Shadow JM26 or an SRK

I dream of making a head that could screw onto an SRK body and use an MTG2 with a useful reflector.

Are you referring to this driver:

http://www.kaidomain.com/product/details.S020148

http://www.lck-led.com/26mm-9000ma-driver-modes-sst90-p-863.html?cPath=37_135