Luxeon reversed polarity? ; QC problem??

Interesting. That could have been a nasty surprise if it had been unknowlingly assembled into a circuit using a stepup switcher. In that case it likely would have fried both the LED and the switcher circuit.
I haven't encountered this yet myself but I am sure that I have handled only a very small fraction of the number of Luxeons that you have.

Don,

Thank you for the heads-up! I am eagerly awaiting my first-ever 5W LS from two sources, and I don't think they come with warranties.

Larry

I thought that manufacturing process for LS is fully automated without human assembly work. If so, it would be very difficult to get polarity messed up in the production line

Alan

wow, that does sound odd.

i guess it isn't that the led was hooked up backwards. it was that the leads were marked backwards.

Originally posted by Alan:
I thought that manufacturing process for LS is fully automated without human assembly work. If so, it would be very difficult to get polarity messed up in the production line

Alan

Click to expand...

<font size="2" face="Verdana, Arial">Yeah, I picture some conveyor or parts going by some QC person when all of a suddon they let a big sneeze rip. Oops there's parts on the floor. Looks around; nobody watching- parts returned to the trays heading to the lead cutting machine.

Now had this LED been atached to the Copia battery I read about that had its label on backwards; a match made by Murphy!

- Don

Don, as you might have heard, I came across a few. Actually about 30% !!!

Fortunately they went into mods after I was well aware of the electronically dyslexically challenged person who assembled/marked them, so the proper actual polarities were observed and soldered up. Those with NexNeedles (and even a few SpaceNeedles) can unscrew their head bezels and check if the red wire is connected to the 5W Luxeon's negative tab.

Being that I am certain this glitch will be corrected shortly (if not already) at the Lumileds production facility, you just might be the owner of a *marginally collectible* light -- the "Dyslexinator"!

I noticed that on my nexneedle. I had to check with my multi meter at first I just thought the wiring was backwards but the pos lead is on the wrong side according to custom.
Chris

Charlie,

I hadn't heard but it makes sense and my goofball came from my bud in the islands so maybe it was a special reel for a special guy.

- Don

Don't worry, we'll settle up when you get here next month. Just bring it with you (I'm about cleaned out of mine) and I shall remit a cheerful refund...

Hey Chris,

Now you can double your money on e-bay...

I seem to recall mention of this before but I ran into a real surprise yesterday! I went to determine the Vf of a 5W SE white that I was potentially going to use in a mod and it didn't light up at all! I usually set my target current on the bench supply and then set the voltage slightly above the suspected Vf. The bench supply shows the voltage at which the current limit is reached. Nada! I figured I had a DOA which would have been a first. For the heck of it, I reversed the polarity; attaching the negative Lead to the LED contact with the side having the short tab hole in tact and the LED lit!

I wonder how often this occurs and if it is something that we need to check every time!?!? This could be a drag for any production runs where the components are assumed to be functional.

Have others encountered this little surprise ?

- Don