Current, voltage, runtimes - enlighten me please

[Jonitus]

On this latest saber, the customer wants green. Fine. For a bright blade, the choices are the K2 or the Lux V. As Tim has none of the green K2, my choice is the Lux V. At 160 lumens, I am not complaining, but how will it affect runtime on a 7.4v 1500mAh pack.

I guess the question is...as the K2 requires about half the voltage of the Lux V but twice the current, how do the two compare when it comes to autonomy of the saber?

K2 = 3.85v @ 1500mA
Lux V = 6.84v @ 700mA

[xwingband]

I still wish I had solid numbers from erv on exactly what voltage his board won't give the V the right current...

That's what will make or break it. Ex.:

By straight math you get 1 hour for the K2 for sure (likely more) and two hours for the V. However if the batteries only maintain the needed voltage for say 50% you'd have the lumen boost for 1 hour then a lack luster remaining hour.

Unfortunately not many out there probably have run the same setup to give hard data. :?

[Jonitus]

That is the downside of running what is still fairly esoteric hardware. In my own mind I thought that the runtimes should be about equal between the two LEDs since they are comparable with respect to voltage and current. Perhaps the saving grace would be the LiIon providing a more even voltage curve than would say an alkaline or a NiMH.

I guess all I can do is install the Lux V and see what kind of times I get.

[Novastar]

I believe that you're basically correct Jon.

Since voltage and current are relational, it makes sense why the LEDs differ for fwd v and current "wants".

However--every LED model is more or less efficient compared to the next.

Plus, Erv's driver allows you to control the amount of "flicker", which will save battery time. Corbin's does this a lot more inocuously, and you cannot "see" the flicker.

So it all depends on a great many things, but again--I say the best test is... turn it on, swing and bang it around for however long you can test it. Once mine passed 3.5 hours I said to 'ell with it!!! It's long enough, hahahah