Direct Draw & Voltage on p2d/L1d/p1d Fenix Question

timcodes

Newly Enlightened
Joined
Nov 1, 2005
Messages
156
Hello,

I'd like to understand, but I do not find the answer anywhere.
If the p2d is on direct drive, what would be the current draw? Would this be dependent on the battery's direct current output?
That is on the aw rcr it would be what? In essence depended on the battery?

I know that power = draw*voltage.

Please help me to understand.

Thanks
 

HKJ

Flashaholic
Joined
Mar 26, 2008
Messages
9,715
Location
Copenhagen, Denmark
The best way to find out is by measuring it.

The current will be VERY depend on the voltage and the values for one P2D does not necessary match other P2D's.
 

timcodes

Newly Enlightened
Joined
Nov 1, 2005
Messages
156
The best way to find out is by measuring it.

The current will be VERY depend on the voltage and the values for one P2D does not necessary match other P2D's.

Thanks, that's great, but can you let me know how to do that?
I have a multimeter. Where are the points for me to measure it?
 

HKJ

Flashaholic
Joined
Mar 26, 2008
Messages
9,715
Location
Copenhagen, Denmark
Thanks, that's great, but can you let me know how to do that?
I have a multimeter. Where are the points for me to measure it?


I would get a variable power supply and a 1 ohm resistor, then connect it this way:
power supply + ---- resistor ---- led/flashlight ---- power supply -

Start with the power supply at 3 volt, measure voltage over the resistor (and calculate current from this) and the led. Then increase the voltage in 0.1 volt steps and do it again, while drawing a current/voltage curve.

The stop point would be 1 volt over the resistor (i.e. 1 ampere), this is the rated maximum current for the led.

Then your know that a battery, just of the charger can be up to 4.2 volts, but working voltage is in the range of 3.6 to 3.7 volts.


Measuring direct between a battery and a flashlight is difficult, because the voltage drop over the meter would affect the result and give to low a reading, it is also depend on the battery charge state. But it is done this way:
battery + ---- meter in 10A range ---- led/flashlight ---- battery -
 
Top