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Discussion Starter · #1 · (Edited)
Hi,

I have buyed the SKU 25516 3xCree boost driver in DX to feed my triple XR-E R2 DIY Helmet Light.

http://www.dealextreme.com/details.dx/sku.25516

The Driver will not work at High mode (800mA). After a couple seconds in this mode the driver get off.A crisp sound is present in high mode. In Middle mode and Strobe has no problems.

I use Ultrafire 3000mA/h protected batteries.

Is the driver wrong? Otherwise, is a issues with the protection board of the batteries that not cant supply enought current?

PS: Sorry for my bad english.
 

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The Ultrafire 3000 has a fairly high internal resistance, which is not good for high current devices (like boost-mode drivers). This driver will fall back from high to low mode if the voltage droops too much. This is probably what is happening here.

Ditto what Vancbiker is asking. Are you using 2S or 3S? Using them in parallel, i.e. 4 cells in 2S2P, might be needed since 2P wiring cuts the effective internal resistance in half. If you are strictly limited to 2 18650 cells, then try getting some better, lower internal resistance cells than the Ultrafire 3000's.
 

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Discussion Starter · #4 ·
desolder said:
The Ultrafire 3000 has a fairly high internal resistance, which is not good for high current devices (like boost-mode drivers). This driver will fall back from high to low mode if the voltage droops too much. This is probably what is happening here.

Ditto what Vancbiker is asking. Are you using 2S or 3S? Using them in parallel, i.e. 4 cells in 2S2P, might be needed since 2P wiring cuts the effective internal resistance in half. If you are strictly limited to 2 18650 cells, then try getting some better, lower internal resistance cells than the Ultrafire 3000's.
I use a 2P configuration. I have tried with 2 Trustfire Batteries without protection and the driver dont get off in high mode. But in a short time the light shines very low and the modes dont want work. I will try morning with full loaded batteries.

Thanks for the replys.
 

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Discussion Starter · #6 ·
desolder said:
Anxo - just so i'm clear, you're using a 2S2P, 7.4V configuration, right?
Sorry, i have a mistake. I want to say a 2 Serial configuration.

I Think that the driver is dead. Actually the voltage between the leds is 7.8V with full charged batteries.

I have doubts to buy the same boost driver or buy 3 800mA driver and feed the leds individually.
 

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So it's 2S1P, correct? (two cells in series only, nothing in parallel)

I have three of these drivers. They work fine BUT you must use good batteries that can withstand a high current drain with minimal voltage droop (in other words, has low internal resistance). Otherwise it will drop out of high mode and into low mode. You may need to use four cells in 2S2P configuration.
 

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Discussion Starter · #8 ·
desolder said:
So it's 2S1P, correct? (two cells in series only, nothing in parallel)

I have three of these drivers. They work fine BUT you must use good batteries that can withstand a high current drain with minimal voltage droop (in other words, has low internal resistance). Otherwise it will drop out of high mode and into low mode. You may need to use four cells in 2S2P configuration.
Yes i use teh 2S1P configuration.

Actually my driver has blew up. I have buyed 3 800mA driver for feed any led individually. So can i use two batteries in parallel configuration.

Desolder, thanks for your help.
 
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