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Sky Hawk
08-08-2005, 03:01 AM
I am about to get into electric planes and have a dumb question regarding lipoly batteries.

I am looking at a combo deal where it is suggested that the model use a Thunder Power 730mAH 3S battery that goes along with the Himax 2808-1160 brushless motor and Castle Creations 10A ESC.

My question(s) is, what is the difference between the 730mAH 3S and say a 3S1P 1050mAH pack? Difference with a 3S2P 2100mAH pack?
Also, can someone recommend a place to learn what 2S1P, 3S1P and 3S2P means to a dummy like me?

Thanks,
Sky Hawk

Reformed Nitroaddict
08-08-2005, 03:07 AM
You can learn right here!

When looking at the numbers on a lipo pack the first number is the amount of cells in series, the second is the number of cells in parallel.

IE a 3S1P 730mah pack is 3 cells for a total of 11.1V

If you changed that to 3S2P, then it would be two sets of 3cells in series, wired in parallel, for a total of 6 cells. But still 11.1V, only now you have upped the mah to 1460mah.

Make sense?

For the most part, you will never use cells wired in parallel for models under several pounds. Park flyers work just fine on 2S1P packs and 3S1P packs.

For the record - which plane did you get?

Unbalanced prop
08-08-2005, 03:15 AM
Sky.........The "S" stands for the number of cells hooked in series. A 2S would mean two cells hooked in series or 8.4 volts fully charged. 3S is three cells hooked in series or 12.6 volts fully charged. The "P" is how many series cells are connected in parallel. This determines the mah of a pack which determines the amount of amperage that can be drawn from a pack and for what length of time.

A 3S pack of 730mah would be 12.6 volts (11.1 nominal) and will supply 730 mah. A3S2P of the same cell is basically two 3S packs hooked in parallel to give the same voltage but 1460 mah. The 3S2P configuration can supply more amperage and twice the mah of a 3S pack, but also weighs twice as much.

Doug

Sky Hawk
08-08-2005, 03:17 AM
I am seriously considering the 4D Lite from Tufflight.com

I watched the video on this thing and while it might not be the prettiest bird around, it sure looks like to will handle my learning to fly it and 3D. FYI, I have been flying glow for 4-5 years and now I want to abuse myself some more by learning everything I can about electrics. :p

Okay, I guess this is starting to make sense so far. Would there be any advantage to go with maybe a 3S1P 1050mAH pack over a 730mAH pack? Would there be much of an weight difference, if any at all?


Sky Hawk

Reformed Nitroaddict
08-08-2005, 12:42 PM
Sky - the more mah, the longer the runtime, and the more amps the pack can produce. But yes, it will be heavier.

Most good packs these days are 10C, so a 730mah pack could supply about 7amps of current, while a 1050 could supply 10amps.

Supplying the same amps, the 1050 would add a minute or two of runtime.

Walter Phillips
08-14-2005, 12:50 AM
Sky Hawk. There are no dumb questions. Sometimes there are questionable answers. Welcome to E-flight and Li-po's. The S's and P's will be second nature in no time. Getting good packs at a good price becomes the challange. I have found that I get what I pay for. Have been using some of my Kokam packs for two years.