Razor canister light

[stuartv]

I just learned of this new (to me, anyway) option for canister lights.

I emailed them to ask about the lumen output over time. They emailed me back and said that it outputs at a constant level "over the complete burn time."

4200 lumens
8 degree spot in 60 degree beam
155 W-Hr Samsung battery pack
5.5 hours on High
wireless charging
$1049

The specs seem really nice. Especially for the price.

Do any of you have any experience with this light?

http://shop.gosidemount.com/en/razor-primary-light-l4200

 

[Manatee Diver]

There is no way that they are producing 4,200 lumens for 5.5 hours.

 

[tbone1004]

@stuartv it's also not UN38.3 certified

 

[almostDIR]

There is no way that they are producing 4,200 lumens for 5.5 hours.

most LEDs produce something around 100 lumens per Watt.

Probably it has 40w LED inside I believe. 40W times 5.5hours is 220Wh. Not taking into account any losses in electronics.

I would assume either a little bit lower output like around 3000 lumens OR shorter burn time like 4 hours or so. OR it could have automatic step down mode when the battery is low which would enhance burn time at the cost of light output.

It is easy to cheat on Lumens because they are very challenging to meter reliably even with expensive testing equipment so probably the light output is considerably lower than specified (like 2500 - 3000 real lumens) and they did not cheat the burn time.

 

[loosenit2]

Interesting product. I noticed that it is only rated to 100m vice the much more typical 152m.

 

[stuartv]

There is no way that they are producing 4,200 lumens for 5.5 hours.

The Cree data for the XHP70.2 says 181 lumens per Watt, at binning conditions. And max output is 4292. I am just guessing that 4292 lumens is the "binning conditions" being referred to.

So, a quick calculation says that 4200 lumens would require 23.2 watts. 23.2 watts times 5.5 hours is 128 watt-hours. The battery pack is 155 W-Hr.

Their spec seems believable. What am I missing?

 

[stuartv]

Probably it has 40w LED inside I believe. 40W times 5.5hours is 220Wh.

No need for a "probably". The information is right there on the page I linked. It says it uses a Cree XHP70.2.

The Cree data page for that LED emitter says Max Power is 29W.

XLamp XHP70.2 LEDs | Cree LED Components

29W * 5.5 hours is 160 W-Hr. But, it seems they may not be driving at quite the max power spec.

 

[stuartv]

@stuartv it's also not UN38.3 certified

Which implies that it might be problematic to fly with? Anything else?

 

[wetb4igetinthewater]

Which implies that it might be problematic to fly with? Anything else?

Blowing up when/after charging.

 

[tbone1004]

Which implies that it might be problematic to fly with? Anything else?

which states that it is illegal to fly with

It doesn't really tell you anything else, however since they haven't gone through the efforts of testing it, and knowing what that company has done to past suppliers, I would not be confident in that being a reliable battery pack in the long run. Dangerous? unlikely, but I wouldn't put much faith in it, and certainly means it hasn't been tested by a third party against things like charging and discharging.
Wireless charging is VERY inefficient. Inefficient charging means energy that should be going into the battery is turned into heat, and heat is what usually makes batteries fail. In a sealed canister made of an insulator, it's not a technology I would be comfortable using.