Kv question
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Kv question
Hi All,
I have an older AXI 2808/20 and the Kv rating differs from that of the newer version on Hobby Lobby's web site.
Mine has a Kv rating of 1250 whereas the newer one is rated at 1490.
Here's a [link=http://www.hobby-lobby.com/brushless-axi2808.htm]LINK[/link] to the web site.
I scanned the spec sheet into pdf format and will include it.
My question is what size prop will this motor spin on a 3 cell lipo ?
Thanks,
John
I have an older AXI 2808/20 and the Kv rating differs from that of the newer version on Hobby Lobby's web site.
Mine has a Kv rating of 1250 whereas the newer one is rated at 1490.
Here's a [link=http://www.hobby-lobby.com/brushless-axi2808.htm]LINK[/link] to the web site.
I scanned the spec sheet into pdf format and will include it.
My question is what size prop will this motor spin on a 3 cell lipo ?
Thanks,
John
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RE: Kv question
1250 will probably spin an 8 or 9 inch prop with no problem.
What is the max amperage rating of your motor? You want to prop your setup to optimize your motor, not melt it down.
Do you own a WattMeter, or are you just hoping someone here will give you some kind of magic answer?
What is the max amperage rating of your motor? You want to prop your setup to optimize your motor, not melt it down.
Do you own a WattMeter, or are you just hoping someone here will give you some kind of magic answer?
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RE: Kv question
A magic answer would be nice and I will take that comment with a grain of sand as I'm sure it was well intended.
No the reason for the question is Hobby Lobby gives you a starting point with prop selection to get you in the ballpark for each Kv of the motors they have listed and as I've stated above my 2808/20 Kv does NOT match the one they have listed. Its almost 250 Kv slower.
So after reading the "magic answer" reply maybe my question should have been:
Is there a formula for prop selection by the Kv rating ?
I only have a limited supply of electric props and the two LH'S are not close enough to run out and grab props to experiment with.
Thanks again,
John
BTW yes I do own a Watt's Up. Thanks for asking.
No the reason for the question is Hobby Lobby gives you a starting point with prop selection to get you in the ballpark for each Kv of the motors they have listed and as I've stated above my 2808/20 Kv does NOT match the one they have listed. Its almost 250 Kv slower.
So after reading the "magic answer" reply maybe my question should have been:
Is there a formula for prop selection by the Kv rating ?
I only have a limited supply of electric props and the two LH'S are not close enough to run out and grab props to experiment with.
Thanks again,
John
BTW yes I do own a Watt's Up. Thanks for asking.
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RE: Kv question
go to the DMA site or one of the online calculators like http://www.rcadvisor.com Fill in the blanks with the best info you have and you'll get a starting point. You can play with prop size and battery configuration until you get a number you can live with.
Walt
Walt
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RE: Kv question
Just some numbers from own experience: I have used the old 2808/20 in some planes, and with 3S LiPo. 8x4 gave 170- 180 Watt (far from max), 9x6 gave max recommended power, but I don`t remember the numbers! (I use APC-E props)...