testing a red XP-E, and comparing it to a red XR-C, 22/4/'14: XP-E2 results added in post #32

May I ask why you test voltage, current and lumens? :slight_smile:
I think http://pct.cree.com/ can give you this data from all Cree LEDs.
So am I the only one who knows this or did I ignore something?

I also did a test on a blue XP-E2 (also from Cutter), but no comparison to a blue XP-E. In short: 390 lumen at 2A, maximum=440 lumen at 3A (the absolute lumen numbers are not worth much when measured with a cheap chinese lux-meter that is especially off in the shorter wavelengths of the visible spectrum). I will post a graph later some time (if there is interest in that at all?). I have no green XP-E2, so no test on those I'm afraid.

I have not followed your link now (sorry, internet here is slow at the moment), but the last time I checked Cree's numbers, they had not measured the leds on copper boards, and gave no numbers on the higher currents we like to run the leds at.

Sometimes leds perform better than the manufacturers let us know :-)

EDIT: I had time to look into the Cree tool just now, and they indeed only give numbers for the red XP-E2 up to 700mA. Looking at the tool, a bit odd is that the Vf that they give is a bit higher than what I measured over the led wires (at 500mA it is 0.17V higher). My current setting in these measurements is not more precise than 100mA but still then the numbers that I measure are low compared to the tool (I checked, I did nothing wrong here, my voltmeter is correct within 10 mV, and any set-up inaccuracy would only make the voltage higher, not lower).

nice, thanks for the results ,now we need to find a place to buy those red xpe2.

thank you thank you for these tests! do put the blue one in a thread whereever you see fit =) very very helpful

I will do a blue post ;-)

And the test XP-E2 is in my favorite AA-zoomie for the time being, drawing 1.5A from the stock driver with an Efest 14500 battery :-) :

nice, a red zoomie, you can become the new cat emperor 0:)
settling with my focus adjustable red laser pointer until i can get around to some new builds for now :wink:

Wow, I’ve been looking for how to make an amber zoomie, just like your red one.
Amber ought to work the same as the red — if an amber is available anywhere.
Oh, please …. pointers welcome any time.

I have this one : Luxeon REBEL yellow on PCB - LXML-PL01-0030 on aluminium PCB

NOT powerful, but really nice tint.

Djozz, I love that AA-zoomie you show above. What’s the host and where did you get it?
(I can find what looks like that several places but nowhere that describes what’s inside)
I’d like to put an amber into a host using the stock driver (figured I’d blow up the LED if I tried that with most lights)

http://www.tinydeal.com/focus-highlight-180-lumens-3-modes-cree-r2-flashlight-with-strap-p-100672.html

It is optically identical to a lot of 18650 zoomies, but with AA-size battery. The lens is a larger diameter than the sk68, so it throws a bit better, and IMO it is better looking too. The build quality is very decent.

(are you overdriving that red XP-E2 at 1.5A, or is the driver protecting the LED? getting hot? don’t know what driver is in it, obviously, I’ll get one and try)

The driver in this flashlight is a standard budget AA boost driver that goes sort of direct drive on 14500 li-ions. On li-ions the current is limited by resistances in the system, including on the driver board. 1.5A is ok for the XP-E2, as you can see in the graph above, I would like the led to be driven at 2A so I may swap the driver sometime, or put the led in another host (I have a C8 host doing nothing yet...)

Maybe the Osram Oslon SSL 80? I found them here: OSRAM Oslon SSL 80 amber on Star - Oslon SSL 80 LACP7P-KPKR (KR)

> Osram

mA typ.: 350 mA
mA max.: 1000 mA
V typ.: 2 V
V max.: 2.6 V
Watt: 0,7 W

That’s a higher maximum than the Cree — searching for that available near me.

While searching, that led me to a wonderful collection of LED spectra:
http://www.1023world.net/diy/spectra/

that may be useful for comparisons (much in Japanese I can’t read

oh wow, great site! should come in handy :slight_smile:

Thanks once again for your testing!

What type of use are red emitters most useful for? Besides beeing 8)

Red is the least hard on night vision and penetrates fog and smoke best.

Got one of those Cofly AA-zoomies you recommended,
swapped in an amber emitter
(XR-E on 16mm base from
http://www.fasttech.com/products/1609/10001863/1134700-non-white-cree-xr-e-led-emitters-wbase-plates )

I, er, accidentally de-domed it, while soldering the leads to it.
Fell right off. Guess I got the base too warm.
Oops.
Used it anyhow.

Result is a lovely amber zoomie, smooth flood, nice image of the emitter at zoom.

Now I want to try, I guess an XP-E2? Mouser has the colored Crees — XP-E, XP-E2, and XP-C

Hm. around $2 for XPEBAM-L1-R250-00901
around $5 for XPEAMB-L1-0000-00901
danged if I can tell the difference.
Same pattern for reds and other colors. Time to study more.
Ack.

Any source for amber and red XP-E2s already mounted on a good base?
Else, I’m going to have to learn how to do surface mounting.

inll-outdoor :wink: