LEDs Not Drawing Amps of Old

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Tom E wrote:

MRsDNF wrote:

I’m willing to do testing if someone can tell me what they want done below 5 amps. Anything above 5.5 amps and I can only blow them up. I also do not have any older generation spare XML-2 U2 or U3 leds. I could pull them from lights though if needed.

Really dunno – dunno what’s going on. Seems like conflicting info: Richard says his M6 builds get more output (lumens) with the U3’s, but djozz’s tests indicate high Vf, mediocre output with the U3’s he tested. Your tests in post #11 show virtually no difference in Vf from 1A thru 5A. Others have found high Vf with the new LED’s as well, but your tests are the only ones I’ve seen or heard of where the Vf is basically unchanged between a U2 and U3. Obviously we don’t have all the info, and no idea whether sourcing and tint variations is partially to blame.

As far as I know (I’m ready for MRsDNF to correct me), the numbers MRsDNF posted just show that fresh U2 and U3 parts have similar Vf. MRsDNF didn’t state that it was an older U2..

Still fine, still on a break. One day I’ll catch up with you folks! previous wight catchup Wink
list of my drivers & variants (A17DD, FET+1 stuff, WIP stuff, etc)

Tom E
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Ahhh - could be...

Thanx RacerR86 - I generally order LED's to stock, so hard to say. I'll do lower level amp builds and sometimes max'ed, all depends...

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Location: A light beam away from the missus in the land of Aus.

I dont have any older leds to test. Hopefully I can get an older XML-2 of Rod911 and compare voltages with the the later ones and see what current it goes to. I have retested two later leds last night again without a switch in line The voltages are quite a bit less than previously posted but again very  similar to each other. When I get the led from Rod I'll post it all up.


djozz quotes, "it came with chinese lettering that is chinese to me".

                      "My man mousehole needs one too"

old4570 said "I'm not an expert , so don't suffer from any such technical restrictions".

Old-Lumens. Highly admired and cherished member of Budget Light Forum. 11.5.2011 - 20.12.16. RIP.