Sofirn LT1s etc lack of water resistance

Coulomb.

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I bought a pair of Sofirn LT1s when they came out with plans to use them, among other purposes, as anchor lights on my sailboat.

For those unfamiliar, anchor lights are all-around white lights displayed while a vessel is anchored at night, so that other vessels are aware of the presence of the vessel and the fact that it is anchored; various patterns of red, green, and white lights are used for vessels that are not anchored. While most vessels have an anchor light that is powered by the vessel's electrical system, it is sometimes poorly placed for visibility and since even the best lights can fail it is good to have a spare.

Sofirn's specifications state that the LT1s is IPX8 water resistant. IPX7 means: can withstand immersion in 1 meter of water for 30 minutes. IPX8 means a manufacturer-defined standard that exceeds IPX7.

The lights are simply not water resistant to that degree. In rain or spray, water accumulates on the top of the light where it can drip through the USB-C port (even if the rubber cover is in place) and damage the port and the electronics.

I have also had problems with my Sofirn IF25A failing to charge after extended use in wet conditions.

I like Sofirn, I like the lights overall and have recommended them to others, but at this point can only consider them suitable for dry conditions.

I also have two BLF LT-1. By examination they appear to have similar limitations but so far neither has failed, perhaps because the charging port faces to the side in use, rather than facing up.
 

aznsx

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I bought a pair of Sofirn LT1s when they came out with plans to use them, among other purposes, as anchor lights on my sailboat.

For those unfamiliar, anchor lights are all-around white lights displayed while a vessel is anchored at night, so that other vessels are aware of the presence of the vessel and the fact that it is anchored; various patterns of red, green, and white lights are used for vessels that are not anchored. While most vessels have an anchor light that is powered by the vessel's electrical system, it is sometimes poorly placed for visibility and since even the best lights can fail it is good to have a spare.

Sofirn's specifications state that the LT1s is IPX8 water resistant. IPX7 means: can withstand immersion in 1 meter of water for 30 minutes. IPX8 means a manufacturer-defined standard that exceeds IPX7.

The lights are simply not water resistant to that degree. In rain or spray, water accumulates on the top of the light where it can drip through the USB-C port (even if the rubber cover is in place) and damage the port and the electronics.

I have also had problems with my Sofirn IF25A failing to charge after extended use in wet conditions.

I like Sofirn, I like the lights overall and have recommended them to others, but at this point can only consider them suitable for dry conditions.

I also have two BLF LT-1. By examination they appear to have similar limitations but so far neither has failed, perhaps because the charging port faces to the side in use, rather than facing up.
Sorry they didn't work out. Just to state the perhaps obvious, their supposed 'IPX8' likely does not exceed or (or even meet) IPX7. Buyers beware. This clearly doesn't speak well of their specifications / ratings. I 'second' the thanks for posting this.

EDIT: I've always found that if someone will lie to me about one thing, they'll think nothing of doing so regarding other things.
 
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yellow

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What a surprise
:rolleyes:
what a chinese maker of cheap-to-low priced light states on watertightness does not hold in reality.
:rolleyes: :rolleyes:

You got a light with an additional hole, just covered by a rubber flap, for a use that we could argue needs almost a diving light.
What did You expect?
 
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aznsx

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When I just read a later post here, it occurred that I made an error in my last post in this thread. Let me correct the record.

their supposed 'IPX8' likely does not exceed or (or even meet) IPX7. Buyers beware. This clearly doesn't speak well of their specifications / ratings. I 'second' the thanks for posting this.

What I should have said is that it not only doesn't meet the claimed IPX8, nor IPX7, but it likely doesn't even meet IPX4, which I think covers most 'splashing' exposure, but short of any submersion (IPX7). So it likely isn't just over-rated by 1 rating level, but in fact probably by 2. I mis-typed earlier, and yeah, that's even notably worse than what I wrote earlier. The light likely doesn't meet any standard IPX water ingress level.
 

bykfixer

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What a surprise
:rolleyes:
what a chinese maker of cheap-to-low priced light states on watertightness does not hold in reality.
:rolleyes: :rolleyes:

You got a light with an additional hole, just covered by a rubber flap, for a use that we could argue needs almost a diving light.
What did You expect?
A bit harsh in tone but the logic is sound.

To make it water tight the usb port should be hidden behind o'rings and revealed by twisting or other method to expose it. ie slide to cover it or uncover it with at least one (but probably 2) o'ring blocking the point of entry.

Here's how Coast did it way back in 014
IMG_9690.jpeg

Exposed

IMG_9691.jpeg

Covered

And to aid in water tight they provided a battery that could be charged via usb port outside of the light as well.
 

aznsx

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To make it water tight the usb port should be hidden behind o'rings and revealed by twisting or other method to expose it.
Yep. I consider this long since 'settled science' for charging ports on decent quality lights if one doesn't want to use a proper, purpose-built charging interface connector that's optimized for the application (low-voltage DC power interconnect), environmental factors, etc. Think SL Strion / Stinger, Fenix RC-09, etc. It is one ideal solution for a cylindrical tube light.

That said, as a viable alternative to that, O-rings do work great (also settled science). Any flashlight USB should be doing this yesterday. Similar to that Coast, that's how my (years-old) ASP does it. That's how the latest SL ProTac protects its external charging port. I think I might have even seen references suggesting this is how SF is doing it with their latest vaporware offering(s); although I'm not sure about that because I'm not sure they even exist EDIT: beyond prototypes. That Coast probably isn't a particularly costly light either, so that's no excuse. I don't smell a hint of patents with this approach either. It's just a good example of good engineering, which is seriously lacking in many of today's cheap brands in general; which many people don't seem to understand aren't just so cheap because of cheap manufacturing labor and materials, but engineering quality as well. I can assure you that if the engineering of a product is flawed, nothing can 'make up for' that downstream.

How would one implement it on a lantern? Not sure, but not with a rubber plug in a USB connector opening. At least there's a little real estate to work with. If one insisted on using the USB interface, possibly under a flat-gasket-sealed hinged door, like the floor / end plate on the SL Stinger 2020), rather than a rotating collar / head, etc)? Certainly not with an exposed USB connector with only a removable rubber plug. That's just crummy, and seriously flawed.

You don't always get what you pay for, but almost never get what you don't pay for!:). That said, good engineering doesn't always have to be expensive, just good!
 
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