Testing emitters

Hey, can you test a u2/t6 emitter by rigging leads DIRECTLY to a weakish 18650 battery, say charged to 3.8 volts? I have like 5-6 questionable emitters, and I’d rather not go through the the hoo-hah of connecting a driver and all that. But I also don’t want to toast the driver. Direct connection okay?

I would use three AA Nimhs or two AA Alkalines. Less power to the led that way, but a partially depleted Li-ion should work. I would try to keep it under 3.3v, that's why I suggest alkalines.

>>>>>I would use three AA Nimhs or two AA Alkalines. Less

I can do that easily. Have plenty of aa battery holders. Thank you! Sure beats soldering it to a driver and that whole mess.

I use a Cr123A with wires taped to the ends. …. If still blinding bright, use a half dead one.

I’ve used a spare 18650 on an XM-L before, very briefly, although I wouldn’t do that with an XP-G or equivalent - 3x NiMh AA would be better for that.

I test them all the time with a fully charged 18650 just a quick on and of to avoid overheating. I haven’t smoked one yet, but please do not use an IMR 18650 because that could cause a problem.

As long as it's just a blip to see if it lights no harm should be done using an 18650 or even a 3xAA holder @ 4.5V but O-L has the right idea of 2xAA holder just for testing. Safest way to go and the holders are dirt cheap.

Not so worried about burning the emitter as burning a hole in my retina.

His deaf wife as he picked up his hammer and saw.

>>>>Not so worried about burning the emitter as burning a hole in my retina.

Yeah a BIG ditto on that one. I looked directly into an emitter for like 2 seconds while working ona light a couple weeks ago and I had a bright yellow artifact in my vision for like 8 hours. Fortunately it went away, but I won’t be doing that again. And that was a Q3, not a T6/u2.

When I test ’em now, I dangle em into a shoebox with a partially closed cover. Yeah, overkill I know, but the one that got me in the eye was facing away from me when an alligator clip slipped and got me right in the eye from like a foot away. It actually hurt it was so bright.

Well, four suspected dead emitters: Three were dead; one works fine. The toasted ones look absolutely perfect. Well, one does have some burns along the solder point, but two of them look absolutely virgin perfect, but they don’t work. Those were the ones that turned blue before cashing out. Looks like I can assume that a final blue tinge before emitter death really is the emitter and not the driver.

I used two aa batts in a plastic holder and it worked perfect. Thanks to everyone for their help.

I could have used the drained 18650 for just a second, but I wanted to bang the emitter around for a few secs while on to make sure of no loose connections on the star. So since it was more than just a momentary blink, I used less voltage.
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