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Electric Warbird: Help with ESC Selection

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Old 09-12-2014, 11:09 AM
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mark IX
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Default Electric Warbird: Help with ESC Selection

Ok, I need some recommendations for what is a good brand for an ESC. The application is a 1/5 Spitfire weighing in at around 18-20 lbs, 83" ws, and I will be swinging a 24-12 4 blade prop. As near as I can tell, the prop data indicates it requires about 2HP to swing this prop at 6000rpm. The motor I have in mind is a Turnigy CA80-80 with 12S 5000mah, 40C, Li Po batteries (2 6s in series). I would like to be able to program the ESC to set the LVC, soft start, etc. I don't have to have a BEC although it would be convenient. Any suggestions would be helpful regarding selection criteria, brand, current rating, etc.

Thanx, Mark
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Old 09-23-2014, 08:26 AM
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I am also considering a Suppo 7035-8 (80-90) elec motor for my application described above, and I am wondering who has any experience (watt, amp, and voltage readings) with this motor and using a 4 blade propeller. More specifically, I am wondering if this motor can turn a 24-12” 4 blade prop at about 6000 rpm or higher.

Thanx, Mark

Last edited by mark IX; 09-23-2014 at 08:28 AM.
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Old 10-12-2014, 09:26 PM
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It looks like a 120 - 200A HV ESC might be needed.
(Depends on prop size, the make/model of the ESC, etc.)
I'd suggest that you consider using an external BEC.
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Old 10-13-2014, 10:57 AM
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Chuckk2, yeah it looks like that 's what eCalc (from Castle Creations) is telling me. I'm getting current readings around 150- 160 A using a 160kV motor and 10S 6000maH 35C batteries. This is turning a 22 or 24", 12 to 14 pitch 4 blade Zinger prop. Fligt times are around 4 - 6 min . Not sure how accurate eCalc is however. It looks fairly comprehensive. I get better results using 10S than 12S, this was a surprise, too. Better meaning cooler motor temps.

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Old 10-14-2014, 01:19 AM
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"I get better results using 10S than 12S, this was a surprise, too. Better meaning cooler motor temps."
Look at the E-Calc wattage. It's possible that 10S is not using the motor to it's full capability. You may need to
change pitch or length a bit if you have limited choices of prop size.
E-Calc is good, but not perfect. Even with it, you may end up changing a prop size or pitch slightly.

The higher pitched props are usually less efficient, as are the 4 blade ones.
E-Calc cannot completely add the resistance of the high current wire and connectors.
(Too much variation between things.Connectors, wire length, wire size.) At 150A, there can be a noticeable difference.

Last edited by chuckk2; 10-14-2014 at 01:38 AM.
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Old 10-14-2014, 06:22 PM
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Yeah, the motor data shows about 4500W and the motor is rated for 6000W. But when I use 12S the motor temp goes to around 180 deg or more.

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