EagleTac 3-4 Cell Extension Kit - I don't fully understand it.

Esperologist · Sep 10, 2014

Okay, I haven't played around with the extension kit before.... but I've got an M25C2 in my hands and the 3-4 cell extension kit.
I can't find any instructions on how it is supposed to be attached / used appropriately.
From fiddling around, it seems like the battery spacer thing goes between the main body and the extension to reduce rattle when using 3-4 16340 (RCR123A) batteries.
If using 18650 batteries, the spacer thing must be removed.

Is that spacer really supposed to be used with the 4-cell extension?
What are the rubber rings with the body extensions for?

Some of the EagleTac flashlights come with a sleeve that holds two 16340 batteries, so they don't rattle.
It seems like it isn't included with all 18650 compatible EagleTac flashlights, but wouldn't it be reasonable to include them and one with the 4-cell extension?
Is it possible to purchase just those sleeves and use them instead of the spacer with the 4-cell extension?
Well, I guess that last question I should be asking EagleTac. * laughs *

oKtosiTe · Sep 10, 2014

I might be wrong, but I don't think you should be using four RCR's. Four CR123's or two 18650's are accepted.

ragnarok164 · Sep 10, 2014

oKtosiTe is correct. For 4-cell extension, 4x CR123 or 2x 18650 only. Do not use 4x 16340 as that will kill the light.

mudcamper · Sep 11, 2014

Well at least 1 of the rubber rings is if you don't want the tactical ring on, you put that low profile ring in it'S place.

Esperologist · Sep 16, 2014

Well, the 16340s were really just the theoretical of course. I would rather use 18650 or 17650 instead... and 18650 seems easier to get a hold of. Yeah, 2.7V-12.6V means don't use more than 3 Li-ion batteries. Looks like if I take another 3-cell extension and add it on (so I have a 4-cell and two 3-cells) then I could use three 18650s. Meh, might try that out.

I may have to contact EagleTac and ask them for sure what those rings are for and how the insert tube thing works... wonder if I would use the insert if I used 17650 batteries instead of 18650.
In theory, 17650 is just a smaller version of 18650, so they should work... yet bigger than two 16340s, so the 17650 probably won't fit through the spacer.

On checking, the rings with the extensions are the same ring as the cigar-grip cover ring that comes with the flashlight... but why would I need three of them? * laughs *

ChrisGarrett · Sep 16, 2014

Remember, by stacking the cells in series, you gain voltage, but not capacity, so bigger cells, like 2x18650 cells, will yield longer runtimes due to the larger single cell capacity.

With li-ions, I think that using fewer cells, the better.

Chris

Esperologist · Sep 16, 2014

Yes... I forgot about that.

So, batteries in series (stacked) will give higher voltage. Would that result in higher lumens or is it just wasted power?
Those same batteries in parallel (in this case, battery changes) would result in longer run times (or in this case, less batteries to handle during battery change).

If the stacked batteries don't increase the lumens output, doesn't that mean that the circuit only draws a set amount of power... and since lower settings draw less power and provide longer runtimes, if the flashlight does regulate power draw wouldn't more batteries result in longer run times?
I mean, if the flashlight is 980 ANSI lumens with 1*18650, 2*18650 or 3*18650... doesn't that mean it is drawing more power than is available?
Using 1*18650, the M25C2 will run an hour on high output (765 ANSI lumens) or 11 hours on the third output (86 ANSI lumens)... if the output doesn't increase with 3*18650, wouldn't that mean it could run longer since it is like running the flashlight in a lower mode compared to the available power?

I can't currently test that theory, don't have the time right now.

oKtosiTe · Sep 17, 2014

Esperologist said:
Yes... I forgot about that.

So, batteries in series (stacked) will give higher voltage. Would that result in higher lumens or is it just wasted power?
Those same batteries in parallel (in this case, battery changes) would result in longer run times (or in this case, less batteries to handle during battery change).

If the stacked batteries don't increase the lumens output, doesn't that mean that the circuit only draws a set amount of power... and since lower settings draw less power and provide longer runtimes, if the flashlight does regulate power draw wouldn't more batteries result in longer run times?
I mean, if the flashlight is 980 ANSI lumens with 1*18650, 2*18650 or 3*18650... doesn't that mean it is drawing more power than is available?
Using 1*18650, the M25C2 will run an hour on high output (765 ANSI lumens) or 11 hours on the third output (86 ANSI lumens)... if the output doesn't increase with 3*18650, wouldn't that mean it could run longer since it is like running the flashlight in a lower mode compared to the available power?

I can't currently test that theory, don't have the time right now.

Since this light is regulated, runtime will increase with the amount of cells, while output will stay the same.
You should get the best runtime with two high-quality 18650's.

EagleTac 3-4 Cell Extension Kit - I don't fully understand it.

Esperologist

Newly Enlightened

oKtosiTe

Enlightened

ragnarok164

Newly Enlightened

mudcamper

Newly Enlightened

Esperologist

Newly Enlightened

ChrisGarrett

Flashlight Enthusiast

Esperologist

Newly Enlightened

oKtosiTe

Enlightened

Similar threads

Latest posts