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Low output current!!
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#1 (permalink)      3/13/2013 3:23:28 PM US Central   quote/reply + tips
KamoS404
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Low output current!!
I use this driver with XM-L T6 and 26650 battery. It does not have output 2.8 A (as written), but only 1.44 A.
It's a scam.
#2 (permalink)      3/13/2013 8:10:58 PM US Central   quote/reply + tips
django
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You use it with one battery or two in series?
#3 (permalink)      3/14/2013 4:48:24 AM US Central   quote/reply + tips
KamoS404
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I used one and also two. Output was still max 1.44 A.
#4 (permalink)      3/14/2013 5:52:57 AM US Central   quote/reply + tips
django
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+1 details
#5 (permalink)      3/14/2013 5:57:28 AM US Central   quote/reply + tips
KamoS404
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Yes, I measure it at the tailcap.
#6 (permalink)      3/14/2013 6:00:45 AM US Central   quote/reply + tips
django
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Than 1,44Amps is correct result for 2 batteries. (that means it would be like 2,88 with one battery?)

If you get same result with 1 battery, than your multimeter leads are not good. FInd some better leads, and youll get correct readings ;)
#7 (permalink)      3/14/2013 6:01:04 AM US Central   quote/reply + tips
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geek
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+1 details
An easier method to test is to use a bench power supply to make sure enough juice is available to the driver. We have just tested one with a bench PS and confirmed it can output 2800mA.

If you believe yours is defective, open a ticket to have it exchanged. Thanks.
I'm not a CS staff but I help answering questions here. If I missed your questions, I apologize and you are not being ignored :).
#8 (permalink)      5/18/2013 6:26:44 PM US Central   quote/reply + tips
JTech
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I believe the specified current is the LED current not your input current KamoS404.
So you are doing it all wrong.

Hook up the driver to a regulated power supply and measure the current through the LED with a good DMM and thick leads to it.
#9 (permalink)      6/2/2013 5:18:42 PM US Central   quote/reply + tips
eebowler
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If the LED is supplied with 2800mA, and voltage to the LED is assumed to be 3.20V, Power to the LED would be approximately 2.8x3.20= 8.96 Watts. If the Driver were 100% efficient and there was no voltage depression from the cell, then the current measurement at the tailcap for a single cell with a voltage of 4.2V would be approximately 8.96/ 4.2= 2.13A but of course, due to inefficiencies in the driver and depression of the cell's voltage under load, current at the tailcap is usually close to 2.8A.

Now, with two cells in series, bearing in mind that the power to the LED is the same ie 8.96W, when the input voltage is 8.40V, given 100% efficiency of the driver and assuming there is no voltage depression, current measurement at the tailcap would be idealy 8.96/8.4= 1.06A or a little higher in the real world which makes the measurement of 1.44A with two cells correct.