ANOTHER STUPID QUESTION

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Cajun
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ANOTHER STUPID QUESTION

Post by Cajun »

Knowing the Mah battery rating and the amp draw of the motor, what is the equasion for determining the flight time?

I know Lee had it in one of his posts a looong time ago, but I can't seem to find it.

Thanks in advance.[8D]
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boiler
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Post by boiler »

Mah rating of battery divided by 1000 is the amp hour rating. Let's say the battery is 2000 mah. That is 2 amp hours. The battery should be able to deliver 2 amps for one hour or 4 amps for 1/2 hour or 8 amps for 1/4 hour or 16 amps for 1/8 hour. For a round of combat 1/8 hour is about what you need. That being said, If you multiply the amp hour rating by 8, that is the current draw you can take from the battery. A 1 amp hr is only good for a 8 amp draw. A 4 amp hour is good for a 32 amp draw. Would you say that is about right Lee?
Cajun
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Post by Cajun »

Bob, for a school teacher, you sure make that difficult.[:o)], and my thick head hasn't got it yet.[|)]

Lets leave out the combat analogy and convert it to a simple formula. I am a simple person [xx(] and require simple solutions.
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boiler
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Post by boiler »

How many amps does your prop/motor/rpm draw? Divide that by eight then multiply by 1000. That is the mah battery required for the power plant to fly a round of combat. If you don't know what your system requires to fly, you can't determine the minimum battery capacity needed for a combat round.
BenJammin
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Post by BenJammin »

The formula you are looking for is:

battery capacity x .06 / motor amps = approx. minutes of flight time

Example

Pack capacity is 1000 mah, motor draw is 12 amps

1000 x .06 / 12 = 5 minutes
Cajun
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Post by Cajun »

YES, Thanks Ben.

That's what I was looking for.

Now, if I can just keep up with it.[;)]
Lee Liddle
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Post by Lee Liddle »

If you know how many C`s you are pulling, you can just divide 60 by your C draw and get your minutes.

2000mah battery at 20amps is a 10C draw. 60/10 = 6 minutes.

5C = 12 min
10C = 6 min
12C = 5 min
15C = 4 min
20C = 3 min
30C = 2 min
Vapor52
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Post by Vapor52 »

Pinecone
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Post by Pinecone »

The HXT packs have a spotty history. Supposedly the current ones are fine.

The Zippy-H or -R packs are supposedly very good.
crash_out
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Post by crash_out »

We've used the Zippy and Loong Max packs, and they have all performed great. I heard the same on the HXt packs-initially they were iffy, but are supposed to be good now.
BenJammin
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Post by BenJammin »

I've wanted to buy some 4S 4000 packs from Hobbycity but seems like they are never in stock.

I did find these:

http://stores.ebay.com/batteryworld-123 ... idZ2QQtZkm

I've got 2 of them. Seem to work as advertised.
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