EDIT 1:
did a few measurements...
http://photography-on-the.net/forum/sho ... 47&page=13
Turned off: 10 µA
Sleeping: 10ma
Idle: 15ma
Idle with FT-16s: 40ma
Charging capacitor(at full-power): 4.8A (looks like it's limited to this)
the consumption "turned off" is way way lower than i expected, so its safe to let the battery inside for a few months with no problem whatsoever.
the circuit looks very efficient power-wise, low heat generated inside, so this should reflect in "long longevity" (but time will tell )
as current looks limited, its safe to li-ion with large capacity/low impedance with no problems (Yn-560ii for example does not have limit, DIY battery packs can burn the flash unit)
so good so far. finally a cheap and DIY friendly li-ion flash
EDIT 2:
now i realized i can run 2 flashes with one battery pack (1 flash = 1900 full-pops, 2 flashes = 900 full-pops). will make them with two output connectors on each battery pack, so i can use 4 flashes with 2 packs
EDIT 3:
A simple way to calculate flash power is to use the power in watts for each pop. the V850 uses about 0.032Watts per pop, the YN-560II uses 0.045Watts per pop. so we see that a efficient circuit and the higher voltage of the battery makes +25% more efficient than "AA batteries flashes".
EDIT 4: More measurements...
battery indicator:
3 BAR 12.60V ~ 11.35V (3.78V/CELL)
2 BAR 11.35V ~ 10.95V (3.65V/CELL)
1 BAR 10.95V ~ 10.60V (3.53V/CELL)
BLINK 10.60V ~ 5.20V (1.73V/CELL)
The flash measure voltages between capacitor charges, which is very good, and also good average voltages for resting li-ion cell.
its a good idea to replace the battery when the indicator start to blink (empty), the flash will try to get all the power from the battery, but constant "emptying" the battery at low level may reduce life cycles.
also, as current is limited, its very easy to use a AC power adapter to power this flash, and use as "studio flash" (just need to be 12V at least 6A like this). a voltage regulator can also be used (6A minimum recommended), PC power supply, 12V lead-acid battery, etc...
EDIT 5:
opened the battery, they use "Great Power 1800mah" (?) flat cells, with a protection circuit board that monitor each cell. as most batteries that use series cells, this do not balance cells, but monitor each one to avoid overdischarge/overcharge (require matched cell and charge state)
looks like the charger use the standard CC/CV charging, without balancing.
EDIT 6:tested the battery, it really is 1800mah (measured), making around 0.032W consumption per pop
Показать
