12x aa in tripple p7?

[smokeychris]

Hi in my "yet to be build" tripple p7 mag i am planning to put fivemega's 12aa to 4d adapter in it. Eneloop aa 2000ma is my battery of choise. Now my question is: Can someone explain to my what to expect from this pack? Does it give enough amps to the leds to go fullpower en maybe somebody knows for how long? Also i am looking for a charger for the 12aa adapter that can be used in the netherlands. The link in fivemega's post for chargers is 110 volt only. many thnx for any help!

smokeychris

 

[VidPro]

3 p7 run at what current?
i would already say piece of cake, because 4 of them can run a MC-E hot.
about any 12 ni-mhy can put out an Easy little effort 12W of power, with minor warming.
the 2000 enloop thing can do a 1C or 2amp output without to much trouble
see http://www.candlepowerforums.com/vb/showthread.php?t=79302
as you can see so can most of the rest of them too.

for your charger will you be charging them as singular cell items removed, or trying to charge the whole pack in series, or Both to get the best of both worlds, series charging for ease, and singular charging for care and checking and testing?

 

[smokeychris]

I dont know what you mean with current? 12x 1.2 volt = 14.4 volt and yes i want to be able to charge the whole pack at once. Somebody told me that the tripple p7 will pull 9 amps so is this correct with the setup i am planning to use (der wichtels kitt).:thumbsup:

 

[VidPro]

9 amps is probably the rating when the 3 leds are wired in parellel.

with the high starting voltage you indicated, you might find driver items that will work that setup with LEDs in series easier than going high amps in parellel.
the watts of total power dont change, the work that the battereis do doesnt change much, it is just configured so there is a higher voltage and less amps running through anything.
with the high amps running through stuff, drivers even wiring will have to be lots more capable . if you wire the 3 leds in series, then the drivers only have to handle the 3amps, with the higher voltage stuff.

just totally depends on the driver of course. I am just indicating that there are more higher voltage lower amperage drivers, than there are high amperage drivers, and with higher voltage and lower amperage there is often less losses through everything.

and not to complicate it any more, but charging the 12 batts in "series parellel" adds more issues and problems than charging them in "series only", so generally the 12 would be used with the voltage your indicating. once you have that voltage, you potentially CAN run the leds in series. But of course there are things about that too. like the input voltage (your battery) the driver (will it be boosting bucking regulating or multiples of that) and the total voltages of the leds . . . SO you can have both sufficient voltage potential, to get to the current desired through them.

 

[VidPro]

to try and regulate all this (assuming your going to regulate)
i would frst attempt to guess the voltage Maxes and voltage mins of the battery & then pack under the load.

12xNi-Mhy "hot off the charger" max could be ~16.8v (but not at a 3 amps load) this voltage could exist for a mere micro seconds using PWM on some really Low setting (so it is possible to exist)
assuming a 3 amp Continuous load, we then refer to http://www.candlepowerforums.com/vb/showthread.php?t=79302
line K section F and check out the orangey colored line, for this battery and others too to get an idea of where things will be generally.
and we get about 1.35v for the enloop at 3amp load. X12 = ~16.2V
so the top end voltage (under load) were looking at is ~16.2v

discharge the whole thing down and the cells are all lower, and we want to stop before one cell item drops to neer 0v
and look at the other end of the chart , where the voltage starts to drop fast.
~1.1v or 1.0v , then we guess in, that some cell item might drop faster sooner and the LOW ~13V, a good cutoff place might be ~12.5-12.0v , max possible low as ~11.5v where it could start damaging a cell.
so then we range the battery pack at 16.2v-13v "working range". (sure its a 14.4v pack, which doesnt provide enough meaning to do all the electronics)
We dont forget that hot off the charger it Can be higher, and we dont forget that it Can discharge lower, this is just a good range for it.

(i am showing my work so you can adjust it to fit needs, and so if it is wrong myself ,and others can correct all my errors)

---------------------------------------------------------------------

Then you take the leds and do the same analisis:
what is the drive current you wish to push to into the LED, what approx voltages will need to exist, to get to that current.
That varies somewhat based on the "bin" on some items, and can vary so much, it is cool to be able test the ones you actually have in your hand.
for the P7 we can attempt to gain info off the manufacture, by going to http://www.seoulsemicon.com/en/product/prd/zpowerLEDp7.asp
and opening the PDF for electrical managment, or the Main specs for the part. then hoping much of it actually applies in reality
where it claims to have a voltage of ~3.3v at ~1000ma , ~3.6v at high amps ,and max voltage of ~4.2v (where it get hurt bad)
and I get ~3.6v at high amps.
looking at that i would assume nothing and find users here who tested it, but its a start.

In parellel we will need ~3.6v for a megadrive on it, pluss the losses along the way here and there.
3 in series we will need ~10.8v for the mega drive, in series there will likly be less losses along the paths

if were going to have some Max drive on the leds, and we have above battery voltages, it would be best to run the leds in series at ~3Amps then in parellel at ~9Amps

Series
---@---@---@--- ~10.8V , ~3 amps overdrive

->--@-->-@->--@-->- current (Amps) flows through all 3 similar as long as you have the voltage

Parellel
|-@-|
|-@-| --- ~3.6v, ~9Amps overdrive (lots of amps possible but not as practical with battery source type)
|-@-|

|-@- --- 3amps -|
|-@- --- 3amps -| current flow can vary slightly depeding on how each led reacts not so good :-( but can work
|-@- --- 3amps -|

Because of the amps, and having enough voltage available i would choose 3X series.
------------------------------------------------------------------------

Then you find a driver that will work with those Input voltage RANGES at those input currents, and output the led voltages needed to reach the leds desired currents.

WHY:
because to choose a driver item, the driver is going to try and control the current flow, and many are restricted in:
current max input
current max output
voltage input max
voltage output Max
bumping up the voltage (to reach the current)
bumping down or clipping the voltage (to reach the current)
and the elusive just converting the watts of power to different voltages (to reach the current).

Without confusing that the LEDs are "Driven at a specific Current", just that you have to HAVE the voltage, and control the voltages (somehow) to reach that current.

-----------------------------------------------------

soo battery voltage under load ~16.2-13v Leds in series only need ~<11v.
drop through the driver could be up to 2V , meaning it could be regulator that drops 1.5 :-( , it could have protection diodes dropping voltage some, it can have a bit of resistance in the sence thing, it can have a bit of resistance in the switching mosfet stuff like that, but probably not all that, if you want full regulation to the end.
max input ever on driver ~16.8V
max underload general operation ~16.2V
Prefered cut-off or non operation on driver input ~12V
Max needed output on driver to leds ~<11v
Driver that takes higher voltages and reduces them (somehow) will funcionally work in this situation
Max current through driver parts ~3amps

and that is the picture I end up with (usually with way looser figures) , wasnt that fun

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Der Witchel driver (from what i understand)
http://www.candlepowerforums.com/vb/showthread.php?p=2545117#post2545117
is a Buck, wants higher input voltage than output voltage (got that)
works down to 4.2V (ok) (wont really work at low voltage better to use series)
will output 2.8amps (cool) (wont DO 9amps would need 3 to do parellel)
can drive enough output voltage for 4 leds. (Series leds is covered)
drops out of regulation when voltage in is to low (ok)
look like your all set.
only thing left to check is its voltage dropping quantity or regulation style
only thing left that would be nice to have is a low voltage cutoff, or low voltage warning at least.
and that is a VERY high drive current for the led.

 

[smokeychris]

WOW that was a lot more info then i expected lovecpf.
I realy need to work on my elektronics skills i believe because some parts i do not fully understand( but i got some friends who do!) But does it mean that with der wichtels driver running the leds in series each led will get the needed 2.8 amps and thus beeing as bright as possible or maybe i need to look to your post again? I realy like all the info you got for me!

 

[alpg88]

i build 3xp7 using Der Witctchel's kit, leds wired in series, i run them on either 6 18650 cells 3s2p, or on 12 eneloops using fm adapter, runtime of course longer on li ions, but it runs just fine on eneloops, i have 1 mode driver (big mistake, should've bought 3 mode), so i can't really do much about runtime, with 3 mode kit i would be able to get more time.
so go for it, 12 eneloops would work just fine. just make sure to get 3 mode driver. trust me you don't always need 3xp7 at full brightness, in most cases med, and low mode will be more appropriate

 

[smokeychris]

Hi the 5 mode driver is soon to be on my way!
But how do you got 6x 18650 in your mag? Its doesnt fit i think? Or dit you put it in another host?

 

[smokeychris]

BTW whats is the difference between a fm adapter and the fivemega's 12 aa to 4d adapter i am planning to get?

 

[alpg88]

oops yes, you rights 5 mode.

there is no difference fm = fivemega, his adapters are the best.

i had to send my 4d tube to Jesus Hernandez to dual bore it. i also had to make my own holder for 18650.
i made a tread about my lights, you can see the pic of it there.
http://www.candlepowerforums.com/vb/showthread.php?t=262913
btw you can fit 6 17670 in unbored d mag tube. or you can tribore it, and fit 9 17670 cells, you should get very long runtime on 9 cells.

 

[PolarBearX]

I'm also considering batt options for the triple p7 while waiting on the new P7 leds to come out.....rather than 12x aa, I think you could do 4x 14500 at 3.7v each, maybe it works in a 1D or 2D mag body without having to be bored out...it would still be well under 20v freshly charged...should work similarly to the 12x aa's but have a question:

which adapter fits 4x 14500 protected cells the best and works with the kit in the smaller m@g body

PBX

 

[arek98]

I have bored 3D Mag with FiveMega adapter (12AA to 3D) and I use this charger.

I have 3 MCE's 2p2s and then in series with shark. Leds are driven lightly only @ 0.5A.

For 3 P7's I would try to use hipFlex. The problem is that it has diameter bigger then mag tube but with little effort you can make it fit :naughty:

I did that for Elephant 2 where it is driving 4 MC-E's (individual led in parallel and then 4 of them in series) at full power.

hipFlex is buck, you need about 11V top for leds at max power (assuming 3 in series). 12 NiMH will be always more.
My shark solution had a problem that with fresh batteries Vf on low was to close to input annd shark did not regulate.

Der Witchel driver should also be good and it is much easier to fit int Mag.