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

Imalent was quick to respond to to this incident, and they said they will ship a new DX80 or the head to me via DHL. ( May,12,2019)

That’s good news DBSAR… :beer:

If they do not require you to send the damaged head back to them, perhaps, if you find the time, you can open up the head and try to figure out where the fire started? Always good to know where lights can fail!

That’s good to hear. It’s better if this kind of thing doesn’t happen.

But when it does, it’s nice to know the company is standing by their product fixing it fast.

best would be if imalent could pay for shipping to have the light sent back to them, thats the best thing really since they made the light they should investigate what happend…

I doubt anyone out in the public would hear back from them what the problem was if the light is sent back. And it is interesting for the flashlight community what happened.

They seen the photos of the damage i’m guessing here, and didn’t request the head to be shipped back. All its joints are glued. once i receive the replacement, i may try to get the burnt one apart to see exactly what burned on the driver. there are many parts rattling inside now, so I’m guessing it really disintegrated inside.

I wonder….would it be possible to design flashlight’s waterproofing in a way that seals when the pressure is from the outside but fails quickly when it’s from the inside?

I’m sure it is.

One already existing example is a ‘good’ usb rubber cap (the one on FT03 looks pretty good) where outside pressure helps sit it better and inside pressure just pops it off.

Something else that comes to mind is a thin elastic membrane that sits flat outside a metal plate with holes.

Pressure from the outside will stretch the membrane inside of each small hole, not braking the membrane.
Pressure from the inside will stretch the hole area of the membrane, braking it.

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.