Review : Utorch UT02 Flashlight (XHP35 / 26650 / usb rechargeable)(in progress)

Pictures are fine from PC .

I have 4 XHP-35 E4 in my TM16. Each one is seeing 1.14A at some 13.1V making 1768 lumens. Collectively, the 4 are seeing 4.55A in parallel and making 7072 lumens.

Edit: The above said for the statisticians. Perhaps it will help figure the variables. It does seem like this light is not running very hard at all and should be doing more. (UT02, I mean)

Yes they are fine, but they’re also a couple of MB and not worth the huge size.
Takes very long to load with the number of pictures on page 1.
1000 pixels width would be more than enough.

Could be a little higher, but you lose efficiency because you need the boost driver.

That’s the advantage of a boost driver. :slight_smile:

I have set the pictures based on the width of the page . Works best in most devices .
If i set them based on pixels they will not show properly on smartphones etc . Anyway , i will reduce the pictures’ relative width .

I am curious what different efficiency values different types of drivers have. I also read that modern boost drivers are much more efficient… If I look at the runtime graph of the U21, I’m pretty pleased.

That doesn’t matter.
You have used a lot of pictures of several megabytes each.
Setting the % page width doesn’t matter, it takes unnecessarily long to load anyway, because the files are huge and many in number.
You should scale them down on your PC first before uploading.

Not complaining, but I also have noticed page 1 takes a lot more time than any other page to load…

Ok i will probably do this when i update the review .

Thanks for letting me know , and sorry :slight_smile:

Good point, because i forgot that a linear driver just turns the surplus Voltage to heat = waste.
But in this case the voltage has to be quadrupled (that’s 4x) approximately, which is usually not that efficient.
A.f.a.i.k. boost and buck conversion works much more efficient when it’s within about 20% difference between input and output.

:+1:
Thanks.

Peak output being at 2.5A which occurs with 14.4V, or thereabouts, voltage is a bit more than tripled, not quadrupled, but still… the constant current style puts a heavy load on a dying cell by maintaining voltage at the cost of ever increasing amperage draw from the dying cell. Sounds problematic to me, considering that a hot cell can be a bomb. Factor in weak, cheap, and/or inferior components on the driver to save every fraction of a cent and it’s not a likely candidate for bumping power to for just anyone.

xhp35 has 2 versions 6v and 12v, if you are measuring from led 12v versions current will be half of 6v version. Measure voltage please if you’re measuring from led

No, not according to the CREE spec sheets: http://www.cree.com/LED-Components-and-Modules/Products/XLamp/Discrete-Directional/XLamp-XHP35, not to be confused with the XHP50: http://www.cree.com/LED-Components-and-Modules/Products/XLamp/Arrays-Directional/XLamp-XHP50 which is clearly dual voltage.

It is when the cells are below 3.6 Volts.
And for 2.5 Amperes it will have to deliver more than 10 Amperes.
But a fat 26650 can handle that easily.

My mistake. You are right, sorry

Why does the info say this light has a belt clip? I don’t see one.

Is the sense resistor the one marked in orange in Manker’s driver?
Can you show a pic of this Utoch driver?

i think it’s too small to be Sunt resitor

That’s what I think too.