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Is there a plain simple answer Li-Poly

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Is there a plain simple answer Li-Poly

Old 06-20-2004, 06:49 PM
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Snowball1952
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Default Is there a plain simple answer Li-Poly

I have a GWS Slow stick with ISC 50, 350 c geared motor. A GWS Estarter with ICS 300, 350c geared motor. A SIG Rascal 400 C with a ESC 20 amp, 400 geared motor. I have a Li-Poly 3 cell 1900 mah. It runs the rascal but does get a little hot.
COULD I run the GWS planes with this pack? Is there some kind of regulater I could get to use it on all the planes?
I don't unserstand the language of the rates and all that. If I had a 2 cell 1900 mah Li-Poly pack would it work on all three planes. I don't know what amps they draw. How do you find out what each one draws?
When they tell you to use a 6cell 450 mah pack, What size batteries are they talking about? No one says the size of the batteries, C, sub C, AA, 2/3, 5/4, so how do you know?
A few have tried to explain it to me and I am just so DENSE I am not getting it. THANKS FOR ANY HELP. You all are great!
Old 06-21-2004, 09:15 AM
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hexonxonx
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Default RE: Is there a plain simple answer Li-Poly

could you run the gws with 3 cell 1900?maybe.try it with short flights and check the pack often.if the sig gets it hot thats not good. i think your sig may have the highest amp draw probably around 10 amp but to tell you the truth im guessing.theres not enough info on your pack and planes to say if your in the clear or not.as far as a regulator,i have seen them for rx use with li poly but not for powering drive systems,i would recomend diaplined throttle management,dont keep it at WOT.just enough throtle to keep it up and maybe 3 clicks more with short bursts of full,you know for the ROG or gettin out of trouble.good luck.
Old 06-21-2004, 09:31 AM
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Greg Covey
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Default RE: Is there a plain simple answer Li-Poly

Often, the cell size is dropped now because of the incredible advancements in battery technology over the past few years.

It is easier to speak in general terms if you don't actually measure the current in your setups. For example, in a Speed 400 geared setup, we can assume a ballpark current limit of around 10amps. For the geared Speed 300 or 350 setups, it is about 6amps. This gives you an idea of the current needed to be delivered by the battery whether it is NiCd, NiMH, or Lithium technology.

As for cell count, a 6-7 cell NiCd or NiMH setup translates to a 2-cell Lithium pack. Often, on 8-cell NiCd setups, we option for a 3-cell Lithium pack and assume the use of throttle management will keep our motors safe for a reasonable longevity. The extra full-throttle power is usually only needed on take-offs or loops, etc. A 3-cell Lithium pack is equivalent to a 10-cell NiCd or NiMH pack.

If all else fails, usually the battery type gives you a hint of the size. If you are talking about a 600mAh NiCd battery meant for a Speed 400 power system, this often hints toward a 2/3A size.
Old 06-21-2004, 11:54 AM
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Matt Kirsch
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Default RE: Is there a plain simple answer Li-Poly

Much of it is definitely brute memorization, and getting everything straight does tend to be a daunting task. Unless you really want to become an expert, though, don't worry about it too much. Just ASK
Old 06-21-2004, 02:53 PM
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Snowball1952
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Default RE: Is there a plain simple answer Li-Poly

thanks you guys
Old 06-22-2004, 03:41 PM
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mjasin
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Default RE: Is there a plain simple answer Li-Poly

I am hijacking this thread to ask a simple question! Let's say you have a 2/3A 600mah cell and a 2/3AA 600mah. What would be the main difference (besides size)? Would the bigger cell be able to deliver more amps?
Old 06-23-2004, 07:19 AM
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Matt Kirsch
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Default RE: Is there a plain simple answer Li-Poly

In general, yes. Think of it like 12 clowns in a clown car vs. 12 clowns in a bus. The clowns can file off the bus much quicker than they can exit from the car. Imagine the carnage if they tried to get out of the car as quickly as they could get off the bus.

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