Converting to LiPo
10-12-2004, 03:53 AM
#1
Converting to LiPo
Need some help converting 8 cell nicd to lipo. Motor is Mega ACN 22/30/3, prop is 12x6 folding. Was useing a 45 amp controller with 8 cell 1300 cp nicd pack. All is going in big Glider. 102" ws, 710 in sq area, 51 oz weight, wingloading is 10.5 oz/ft sq. Can someone please tell me what size pack 2s, 3s, etc. I would need and also would It take parellel packs, 2p, 3p, etc.? Also what about esc?
Thanks
Doug
Thanks
Doug
10-12-2004, 08:24 AM
#2
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RE: Converting to LiPo
First things first. The electricity that "comes out" of LiPolys is no different than the electricity that NiCd packs produce. You do not need some sort of "special" ESC to handle it. It's just Volts and Amps.
There really isn't a good equivalent for an 8-cell NiCd pack. A 2S LiPoly is closer to 7 cells, and a 3S LiPoly is closer to 10 cells.
Often, you'll be able to get away with dropping in a 2S LiPoly. This will give you less power, but it's usually offset by the weight reduction from going to LiPoly.
The other option is adjusting the prop size and/or gear ratio with a 3S LiPoly so you don't overload anything. That is, provided your motor and ESC can handle 10 cells (3S LiPoly). With brushless you should be okay in this respect.
How many packs in parallel is a question you'll have to answer yourself. Every brand of LiPoly has a different "C" rating, and they come in many different capacities. To determine how many in parallel, you need a good idea of how many Amps your setup draws, and what cell you've decided to buy. You may have to go with smaller capacity cells and run more in parallel due to space considerations inside your sailplane.
There really isn't a good equivalent for an 8-cell NiCd pack. A 2S LiPoly is closer to 7 cells, and a 3S LiPoly is closer to 10 cells.
Often, you'll be able to get away with dropping in a 2S LiPoly. This will give you less power, but it's usually offset by the weight reduction from going to LiPoly.
The other option is adjusting the prop size and/or gear ratio with a 3S LiPoly so you don't overload anything. That is, provided your motor and ESC can handle 10 cells (3S LiPoly). With brushless you should be okay in this respect.
How many packs in parallel is a question you'll have to answer yourself. Every brand of LiPoly has a different "C" rating, and they come in many different capacities. To determine how many in parallel, you need a good idea of how many Amps your setup draws, and what cell you've decided to buy. You may have to go with smaller capacity cells and run more in parallel due to space considerations inside your sailplane.
10-12-2004, 03:14 PM
#3
Senior Member
RE: Converting to LiPo
Doug,
I would simply replace your 8-cell, CP1300 pack with a 3s2p ThunderPower 4200mAh pack at [link=http://www.hobby-lobby.com/thunderpower.htm]Hobby Lobby[/link].
The 3s configuration is equal voltage to a 10-cell NiCd pack so you'll have extra power, if needed. If not, either reduce throttle a bit or decrease the prop size.
Good luck!
I would simply replace your 8-cell, CP1300 pack with a 3s2p ThunderPower 4200mAh pack at [link=http://www.hobby-lobby.com/thunderpower.htm]Hobby Lobby[/link].
The 3s configuration is equal voltage to a 10-cell NiCd pack so you'll have extra power, if needed. If not, either reduce throttle a bit or decrease the prop size.
Good luck!
10-13-2004, 05:20 PM
#4
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RE: Converting to LiPo
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