Yeah, Iām not entirely sure what is causing it, but it seems to be fairly common with the XP-G3 and XHP50.2.
The fact that I have seen the exact same behavior from both of those leads me to believe there is some sort of manufacturing flaw with this die that has gone unnoticed by quality control at Cree.
Since they sometimes recover with pressure, my first guess would be something to do with bonding the flip-chip die to the external package.
Thankfully it seems isolated to only those 2 models, as the XP-L2s and XHP70.2s I have used are all going strong, even with some serious abuse in a few of them.
I own heaps of XPG3s never had this issue. I think i own 10 XPG3 emitters they all still work fine even after being driven really hard. What boards are your XPG3s on?
Various, but all DTP and mostly noctigons. I have probably more than 30 of these emitters I have used in various builds for myself and others, in that process I have had 6 failures. I have had 3 XHP50.2s fail out of probably 12 or so I have used. That is a relatively small sample size, but they are at least from various batches. I have also seen quite a few posts from other users here with issues using these emitters.
The ones that do work can take a beating, but some just die even with a relatively light loading. These are purely my experiences, so YMMV.
My C8T is a killer, 80.000cd just after switching to AR lens. I will post a review,just couldnāt find time lately.
Unbelievably this light have same size hotspot from 5 meters like UT02 which have much bigger reflector. :+1:
Jarl! I am also to post a C8T review pretty soon, with a freshly loaded 30Q cell I've been able to measure just above 6A at the tailcap with a custom built shunt.
Candela figuresā¦ don't really know what to say. I've measured up to 102.4Kcd but of course my smartphone's luxmeter may not be very accurate.
Stepdown time is ā3:25 in my early sample, measured up to 52.8Ā°C at the head fins just after stepdown.
Medium mode, handled via a low power MOSFET, should be PWM free but I haven't tried to check it out, may someone suggest some tool like an Android app? Can be from any source.
I just sent a mail to visosystems and said that they should fix their flicker tester app for android.
Maybe it helps, you could always borrow someoneās iPhone and download the app to check the flicker.
Edit: Got an automatic mail back saying heās not in office until Dec 3:d so better find someone who have a iPhone you could borrowā¦
The whole C8F thing is a different e-switch beast now, Tracy Wan agreed to send me a unit 4 days ago. Told her about its somewhat steep retail price. She told me it comes bundled with a high discharge cell, yet I can't find any claim in this regard in the selling page advertisement.
phew
I am glad that I got one for ~20$
a price between 30 and 35$ is what they should aim for.
the high discharge cell is not a reason to boost the price that much.
a 30Q is 5$ for end customersā¦
I bought the first c8f and immediately the leds quit working Iāve tried working it out with Cissy and Sofirn but they havenāt been easy to work with, Iām waiting on a response from her right now to see if at least they will refund my money but they havenāt acted very professional in my honest opinion. I would tell everyone to proceed with caution if youāre buying from them. I will update later as to the outcome.
Of course, the new C8F price is nuts. If this is because of hand-crafted custom parts I believe this is an error in this market segment. We'll see if they can fix this.
I really hope that isn't the cell bundled with the new C8F. :facepalm:
Cheers ^:)
P.S.: Andybibbville, at the very least ask them to send you a unit of the new triple MCPCB with XP-L leds, that way you can fix it up yourself or with minimal help from some soldering iron equipped friend.