mod --> UltraFire Cree C3 5-Mode Flashlight with 2xAA

[freedom2000]

Hi all,

Does somebody know if the replacement of the P4 Led by a CREE Q5 one is possible on this flashlight : UltraFire Cree C3 5-Mode Flashlight with 2xAA

I already know that the P4 led is accessible simply and could be replaced by this one : Cree Q5-WC LED Emitter with 14mm Base

So my question is rather on the driver side... which I don't know too much. It seems to be a boost driver providing about 800 mA current.
What will be its behaviour with the Q5 led ?

Any idea please ?
Thanks
JP

 

[freedom2000]

I finally succeeded in disassembling the head...
Here are the parts :

I have mounted the P4 Cree led on a copper (flattened) pipe for current measurements :

and driven the led with the original driver which seems to be a kind of boost driver with rather poor quality assembling...

All this has been tested with 1, 2 and 3 AA NiMH batteries. I have measured the battery and led currents in all (low, med and Hi) modes of the driver.

and here are the results :

1 AA

Battery current
low : 70 mA
med : 180 mA
hi : 510 mA

Led current
low : 10 mA
med : 30 mA
hi : 120 mA
​

2 AA

Battery current
low : 110 mA
med : 300 mA
hi : 840 mA

Led current
low : 30 mA
med : 110 mA
hi : 320 mA
​

3 AA

Battery current
low : 130 mA
med : 340 mA
hi : 980 mA

Led current
low : 70 mA
med : 210 mA
hi : 640 mA

​

In conclusion, the driver has a rather poor efficiency with 1 or 2 AA cells (dispite the fact that the led is quite bright)
When driven in full mode with 3 AA we can achieve 640 mA current into the led (with a total current of 980 mA out of the cells)

So possibly a 3rd extension tube for this ultrafire C3 would be a good idea :wave: http://www.dealextreme.com/details.dx/sku.4438

JP

 

[phreeflow]

Great info and fantastic pics!!! :twothumbs I have the extension and this light is certainly MUCH BRIGHTER with 3xAA but I really don't like the form factor at that length. It's so long that it sticks out of my pocket and is just clumsy to use IMHO :thumbsdow.

Have you just decided to go with the 3xAA option or were you able to find a driver that's able to properly driver the Q5?

Thanks again for the great pics/info. :naughty:

 

[freedom2000]

I will go for this one

It has rather good critics, and I like the possibility to tune the voltage.

I was very tempted to buy the third extension... but didn't do it as I was afraid to get a very weird flashlight...

Thanks for having confirmed my first impression (too long) :wave:

JP

 

[phreeflow]

Looks like a great driver...would love to see the results once your done modding your C3. We would really appreciate a follow-up post once your done with some pics/measurements. :naughty::rock:

 

[freedom2000]

Looks like a great driver...would love to see the results once your done modding your C3. We would really appreciate a follow-up post once your done with some pics/measurements. :naughty::rock:

for sure I will do it :welcome:

JP

 

[freedom2000]

I have just received my Q5.
Here are a few pix of the Q5 and the P4 leds. Both are driven by a constant current of 1050 mA.

On the left is the Q5 and on the right the P4
The pix have been taken with real underexposure.
The Q5 is brighter but not too much...
the purple fringing is due to my camera (not to the leds )

I am now waiting for the new driver

JP

 

[Bigsy]

Let me know how you get on with that driver. So far I've had 5 of them and not had one work reliably with modes yet.

 

[freedom2000]

I will let you know as sson as I will receive my driver

For the moment I am testing my leds with a LM317 chip using this circuit (with a 1.2 Ohm 2W resistor to get the 1A current) :

JP

 

[phreeflow]

Thanks for keeping us updated Freedom2000. :thumbsup: I'm a bit surprised that your Q5 isn't much brighter than the P4 and a little bummed to hear Bigsy mention that the driver hasn't worked out well for him. I have both on order..we'll see. .

I can't wait for them to arrive

 

[phreeflow]

Great pics by the way!

 

[freedom2000]

I'm a bit surprised that your Q5 isn't much brighter than the P4 .

BTW, I think that a direct pix of the led doesn't reflect the exact brightness . Both P4 and Q5 are sooo bright that they over expose a lot the picture. The use of a lux meter would be much more accurate, but I don't have one :candle:

JP

 

[freedom2000]

Hi again --> some news pix

I have done the following :
- put the P4 (respectively the Q5) into the head of the ultrafire C3
- driven the led with the LM317 at 1A current
- directed the beam on a white door
- shooted a picture of each at the same distance, in the dark, with manual identical exposure, defocussed to avoid noise

Here are the results --> the Q5 is brighter (see histogram and pix) and a little warmer than the P4.

thumbnails of the two shots :

P4 only :

Q5 only :

Look at carefully the histograms, the Q5 one is shifted to the right --> Q5 is definitively brighter (but not too much) :thumbsup:

JP

 

[freedom2000]

Bad news today...

I have received my new "universal driver" from DX... soldered the wires; tested it with 1*AA and then with 2*AA NiMh.

But it doesn't work at all --> no light into my Cree Q5 :thinking:

I am afraid that this driver is a kind of "random process"

I have requested support from DX

JP

 

[Bigsy]

freedom I have some bad news buddy: http://candlepowerforums.com/vb/showthread.php?t=195356

5 boards from KD, 5 boards from DX, 0 working boards.

Looks like one massive faulty batch of boards to me!!

 

[freedom2000]

Right !!!

I just came to the same conclusion in your thread

Do have asked for replacement to DX... Do you think it will work ?

JP

 

[Bigsy]

I had a batch of 5 from DX, I soldered 3 and they didn't work. I tested the other without soldering and they didn't work.

Soon as I 'could' of burned the first 3 I asked DX for an extra 2 as replacement which they sent me. They didn't work either.

When I asked for the 2 replacements I ordered 5 from KD, none of them work either.

So thinking about it that's 12 boards :/

 

[freedom2000]

you can now ask for 12 replacement units !!!

If one is working please send it to me

I have only one which is not working... and soon (4 weeks) get a new (non working ??) replacement one

JP

 

[Bigsy]

I have informed Jerry at KD to check his batch, and to get 5 replacements, KD are rubbish though and will probably ask me to ship them back before sending anymore. I can;t be bothered with that, I'd just order more...If I thought they would actually work.

As with the 2 replacements from DX, I'm not going to bother, I know my replacements for the replacements won't work.

Basically I'd given up on this driver, I decided to to order a couple of the DX DI dropins and take them apart to use the bits. $16 for a Q5 I can use on something else and a high power driver isn;t bad. Least I know they will bloody work!

Oh BTW ZERO boards work, that's right not 1.

 

[freedom2000]

Oh BTW ZERO boards work, that's right not 1.

Yes it's right --> 0 boards work among a total of 12 + 1 = 13 boards :welcome:
JP