My Imalent DX80 caught fire, vented smoke, almost exploded (replacement head arrived)

What came to my mind is asymmetric o-ring groove, normal on the inside but somewhat open on the outside, so it’s easy to blow out the o-ring. Zero added cost but I’m afraid of dirt accumulation on the greased o-ring.
I haven’t heard of any BLF light exploding, ever. I hope I never will. Nevertheless I think it would be good to add safety vents in case it happens one day. However something that adds cost or reduces practicality just feels like overkill…

More thoughts:
Initial guess is that the cause of the explosion is a sloppy soldering job.
Can we trust our manufacturers to do better than Imalent in this regard? I’m afraid the answer would be “no”.
Which reinforces my thinking that it would be good to think about safety vents at the time of designing new lights.

Can we program at least some of our drivers to have overcurrent shutdown? It would protect from shorts on the output side but not those before it (right?). Still seems better than nothing. I think that the answer is “no, we can’t do such shotdown without adding cost” for most drivers. But I’m not sure…
Maybe hard shutoff on severe overheat would work? Seems to be something more portable across drivers but acting slower.

Hi,this is Ethan from Imalent, Hope you are OK.

I am ok, the small burn on my finger is healing. One of the representatives from Imalent replied to my email about the incident, and told me they would sent a replacement. I appreciate the concern and fast response to DX80 incident.

  • Den

UPDATES,May,16,2019

The replacement head arrived today for the DX80. I thank Imalent for the fast & great customer service, and quick solution & replacement of the failed light.

(I managed to get the burned head apart… it looks like the driver nearly exploded, (several of the components were blown off the driver board completely, and some of the large copper traces were melted off. My only guess here either one of the square large inductor coils shorted, or a trace close-shorted to cause some high-amp DC arching, (like a welder affect) maybe someone more experienced with circuitry could identify what happened here. (it happened when the light was cold and when turned off, and occurred as soon as i tried to turn it on.)

The big squares look like inductors.

It it would be interesting to have a picture of a "non burned" driver for comparison

Nice disaster pics…. :+1: . :wink:

Wow. That is a fairly impressive cascade failure. You’re right, there was definitely some high-current arcing in there. If you hadn’t quickly unscrewed the light, it could really have snowballed.

Those grey squares are usually inductors. Looking at the upper centre of the first photo, it looks like there was an inductor there at the epicentre of the failure. My first thought was an internal short in the inductor coil, but the loose inductor you show in the third photo looks too intact for that (I’d expect it to have blown apart and look like a worse version of the broken inductor with the wires hanging out at the centre-right of the first photo).

Pure speculation, but I’m wondering if there was a bad solder joint to the inductor in the third photo - one contact looks better than the other. A bad solder joint would heat up under load and could well melt the solder into creating a short. Flash vaporisation would then blow the inductor off the board, causing other components to fail because the circuit was no longer operating as designed.

Another possibility would be a PCB track under the inductor that was damaged or too thin, so it had too high a resistance and heated up under load. If that gets to the point of a thermal runaway, it can vaporise the track and possibly kick off more shorts and failures next to it.

I have to say, I’m surprised Imalent didn’t ask you to send the head back. If I were an Imalent engineer, I’d definitely want it on my bench for a post-mortem comparison with both an undamaged driver and an unpopulated PCB.

I’m also surprised it wasn’t the electrolytic capacitor (still intact at the lower right of the first photo). In my experience, things going pop like that are most often down to a failed capacitor.

Just came across this thread….scary stuff

Glad that nothing worse happened and good also to see Imalent do the right thing

Where did the replacement light ship from? You got it very fast.

They shipped it via DHL priority. (was less than a week arrived.

If I where the manufacturer, I’d want that head back pronto, and try and figure out why it burned. Seems strange they don’t care.

I’m glad minor burns was as bad as it got. I have to say I’m surprised it doesn’t happen more often. Or maybe it does and we just don’t hear about it? It makes me think I should loosen all my tail caps when I leave the house, if that were to happen when no one is around it could burn the house down.

The photos probably helped determine its likely a component failure or bad trace/solder point. its likely an isolated incident, as like any electronic component, every now & then a bad one fails. Remember the 7880 20-mode driver fire i had a few years ago in a single AA light? that little firecracker went off like july-4th on three NiMH AA cells in parallel.

I started loosening the caps months ago just in case. Something none of us want to think about, but we know there will always be a certain risk that we have to live with whether we like it or not.

Same here. Better safe than sorry. Pretty much the only light that’s “live”, is the light I actual carry.
All my lights come with batteries, and almost all the Li-ion ones are mechanical locked out.
Unless that’s not possible, like Cu, Ti, and SS lights, and lights with flaky matte ano.
Those lights I store with a plastic disk between tailspring and anode.
Most of them are in the same place (cupboards). If one battery goes rogue, it will be like the 4th of july.

ALL my tail caps are loosened in my smaller lights[Initial reasons are parasitic drain and accidental activation] and my bigger lights[3 or 4 batteries w/ carriers] have the batteries in big pill bottle w/ silica gel packet,until I use them. I also have silica gel packets in ALL the body tubes. I started this in 2013 when condensation became an issue w/ some of my lights,starting w/ the TK75 which I started and what turned out to be a massive thread for a few years[CPF]

NOW after reading this thread I have another and BETTER reason to loosen tail caps! :sunglasses:

my god

My DX80 blew up again, WTF!
I mechanically locked it out before use because the damn button is so easy to turn on. I twisted the light and tried to turn it back on, smoke went to the glass, light stinks and now dead, SUCKSSS!

sigh…. guess they should switch name, from Imalent to Imminent death instead… :person_facepalming: really ditch that crap and buy it a better brand like olight,acebeam etc with better warranties and quality. its awful how it can happen a second time… their QA is worse then any other brand i know off today.

if that was an american brand u could have sue them for huge money, but since they are from china they can produce whatever crap and get away with it…