Does this seem right?

Hey guys.
So kind of a big day for me today. My C8 turned up wooohoooo! And within 5 minutes I had it in pieces so I could install the bits from 3tronics. These consist of an A17DD FET+1 driver and an XML2 U4-1C on a 20mm noctigon. However I'm now in a bit of a quandary as there's a few things that don't add up in my head.
I decided to do an amp draw test since its direct drive, I have a range on 18650's and wanted to ensure I use appropriately rated ones. Stuck in a fresh VTC5a cycled through to turbo and I'm only getting a draw of 2.2A which to me seems low.
After a bit of digging through Cree's website there appears to be no such led as an XML2 U4-1C. I didn't do a current draw test on the stock light buts it's my understanding that the stock driver is 2.8A (8x7135).
Am I right to be confused by this or am I missing something obvious?
Any info greatly appreciated as I will be a bit disappointed if I've spent £10 to down grade my light.

How did you do the current test? Cheaper multimeter leads have a lot of resistance and can throw current readings way off.

It was with a multimeter. Cost me about £18 iirc (had it years) when set to ohms it and leads connected it reads 0.02ohm resistance so there is a bit of internal resistance. In all honesty my main concern is the lack of data on the led itself.
Edit: just rechecked resistance and 0.2 not 0.02. That may be part of the issue.

Thom2022 said:

In all honesty my main concern is the lack of data on the led itself.

Click to expand...

http://www.cree.com/~/media/Files/C...odules/XLamp/Data-and-Binning/ds-XML2-EZW.pdf

Its an XML2 U4 with a 1C chromacity. Check page 7 and page 16 of the above document.

also have a look here

http://www.candlepowerforums.com/vb/showthread.php?408161-XML2-U4-1A-VS-1C

Multimeters don't read well at low resistances so it's hard to estimate how accurate that 0.2 ohms is but generally it's tricky to measure current with a stock multimeter. Even a good one with thick leads and good connectors will effect the output a fair amount compared to when in the light. The two best ways to measure current I've found are with an inductive pickup meter and a short section of thick wire, or a cheaper option is one of those super cheap meters and you just solder two very short lengths of really heavy wire right into the connector jacks.

scianiac said:

Multimeters don't read well at low resistances so it's hard to estimate how accurate that 0.2 ohms is but generally it's tricky to measure current with a stock multimeter. Even a good one with thick leads and good connectors will effect the output a fair amount compared to when in the light. The two best ways to measure current I've found are with an inductive pickup meter and a short section of thick wire, or a cheaper option is one of those super cheap meters and you just solder two very short lengths of really heavy wire right into the connector jacks.

Click to expand...

Great points. A better test setup, as you suggested, is needed to get truer results.

Hey guys, reviving this thread as I have some more questions. So I purchased a few more bits and pieces lately. Which consist of
(1) C8 with stock 8x7135 driver and XPL hi U6-3A
(2)C8 with A17DD and xml2 U4-1C
(3)M2 with XPL HD V5-2A

So using the same multi meter and the same battery in all setups I'm getting then following current draws
(1)-2.6A on max
(2)- 2.1A on turbo
(3)- 2.2A on turbo

Both lights with the A17DD have had both switch and driver springs bypassed.

I thought the idea of a direct drive driver was to allow as much current as the led could pull so what are they under performing by comparison to the stock driver?
I even swapped out the U6-3A into the C8 running the A17 and the draw stayed at around 2.1A.....
All item description I've seen of the a17dd drivers state 4-6A draw depending on setup.
Does anyone have any idea what going on? I know that the way in testing is not accurate it terms of actual current draw but for the purpose of comparison the only variable is the LED so I'm confused by the 0.5A difference.

Am I missing something?

Anyone?