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Old May 29, 2008, 11:19 AM
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Edina, MN, USA
Joined Oct 1999
11,607 Posts
FYI: .

Originally Posted by Dr Kiwi

"Have an E-Flite Power 32 with a Turnigy 60 amp ESC with 4S 4000 mah batteries turning an 11x7 prop. Watt meter say I'm pulling 56 amps and putting out 570 watts. Should be enough to fly it fairly well."

Well, Jim,

This particular example is fraught with difficulties: The E-flite Power 32 is rated for 42A cont. If he is pulling 56A on 4s and seeing 570W on the Wattmeter he is down to 10.18v (2.55v/cell!) - that will kill 'em in a hurry. Of course, he is confused by saying "putting out" 570W - he is taking in 570W and "putting out" maybe 400W.

At 56A, his pack (let's say 80% of 4000mAh) will last him ~3.4 minutes.

I'm afraid that I cannot go along with this habit of taxing every component to the limit or beyond - heck, I have an 2.5cc diesel Oliver Tiger III, bought second-hand in 1965, used extensively for C/L combat, and which is still in good running order!

Cheers, Phil
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