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Electric Stunt => Gettin all AMP'ed up! => Topic started by: Russell Bond on August 03, 2011, 01:41:51 AM
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Hi all,
Can't wait to use the 13x5.5 prop!!! ;D
Now the questions;
My 690 squ/in plane weighs 70oz fueled, uses 2500mah out of a 3300mah 4s battery and the motor is a Plettenburg 25-10 of 930k/v doing 5.45 secs/lap on 68.5' center to center lines and doing 9400rpm on the original thin epusher 13x4.5 prop.
What I would like to know is will this setup be ok using the new 13x5.5 epusher or am I better off going to the Plettenburg 25-12 that is 770mah and using a 5s battery.
My 4s setup is using 76% of full power.
If the 4s setup is going to run too hot and I have to go to 5s, what size battery do you think I should try? I was thinking about a 3000mah as I believe the 5s setup uses less Mah than a 4s setup, is this correct?
If I don't have to alter the rpm from the 4s setup, this will be 73% of full power.
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Hi Russell
From the tests, those who replaced the 13x4.5EP with the new 13x5.5 EP in general saw the same RPM and the same or slightly less battery usage - I think your baseline set-up will be OK.
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Thanks Dennis, I'm hoping that will be the case. (Fingers crossed!) ;D
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The total energy capacity of a pack is the pack capacity times the pack voltage. When you go from four to five cells, you increase the pack voltage by 5/4, which means that you can decrease the pack capacity to 4/5. In your case that's about 2700mAh.
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Thanks Tim, and less weight!!...Yay! ;D
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Thanks Tim, and less weight!!...Yay! ;D
Is it? I would expect that it would be slightly more, as you'd end up with the same amount of active battery material spread out over five cells instead of four, with more packaging needed.
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Yeah, what I meant was that the weight won't go up (maybe slightly) because the battery can be lower in mah than the 4s.
I was worried the 5s would have to be about the same as the 4s in mah. But you showed me that was not the case. ;D ;D