The specified max input power for this motor is 2450W, on the Dualsky web site. The heading on the spec,, sheet says ;'Max Input Power @ 15S '. Can anyone explain this ??

Brian

"15S" is accepted lingo for 15 Lipo cells connected in series. Figure 4 volts per cell (or pick your own LiPo voltage) and you get 60 volts divided into 2450 wattes yields 40 amps. I would use a high voltage esc in this set-up.
Walt

What is max input at 10S so.

Brian

If I understand your question, the formula is the same: amps X volts =watts (Ohm's Law). So 10S= 40 volts. There are two paths to get the numbers. From the previous e-mail we found that amps =40 therefore 40 amps times 40 volts = 1600 watts.
Alternatively, 10S =40 Volts, Max out put is 2450. Divide that by 40 = 61 amps. That is most likely a maximum burst current. Also you'd have to select your LiPos very carefully to find any that will handle that kind of output current.

What we have learned is that if you want to maintain the same power level on 10S as you had on 15S you have to increase the current (Amp) flow. If you want to maintain the same current flow (40 amps) you will have to accept a reduced power level. Within broad limits either is usually accomplished by changing prop size, given the cell restraints yo cited.

Hope this helps. I retired yesterday (yay!!!) so I've got time to help if you need more.
Happy New Year,
Walt

The way I read the data sheets it says you can go up to 10S not 15S. 2450 divided by 35 (10s under load) equals 70 Amps. I'm sure this is true only if the motor is well cooled.

Jim O

Hey Walt congrats on not having to go to work everyday. I hope I can do the same someday and still enjoy it. Take some time this summer and drive down to the field in Hoffman Estates. We've got a few of us doing E. pattern there. Mike Mueller

Thanks to all for the replies.
Still wonder about this spec,,.
Axi ; 3350W
Plettenberg ; 3500W
Dualsky ; 2450W

Brian

Mike,
where in Hoffman? Shoefactory?
Walt

Yes Walt Shoe Factory. We have the most active pattern group in the Midwest. Around a dozen or so of us doing it. Mike

Show off.........

We have uh, um, well, um, 2 -ish

BTW. The Dualsky is a good motor, so is the Axi. The Pletty is good also, but I have never had one - just seen them. If you try and get 3300+ watts out of any of the motors you listed, have a fire extinguisher near by. They will not be happy. On a 10S battery, you are looking at close to 95-100 amps under load and they will not be happy for long.

Actually I have pushed the Pletty to nearly 4kW (static, around 3500 in flight) when I tested the prototype. It can handle it.

Ratings are related to magnetic saturation of the stator lamination material (as I understand it), there comes a point at which putting in more current doesn't net you any more performance. For instance the original 30-10 motor really would not go above 65A, putting in higher performance batteries, bigger props etc just resulted in more heat being generated in losses and no extra rpm or performance. A huge majority of the changes in the Evo motor was stator lamination material and windings in order to allow the end user to run as large a range of props as they wanted...hence the 100A that the motor can deal with. Obviously the more power you put through the motor the more heat is generated (due to copper losses, which go up with the square of the current nothing you can really do about that), but the magnetics side of things can deal with it. There was a lot of work done on the Evo so that it can deal with this much power in the package its in, it was around 1.5 years in the making of that motor. Running nearly 4kW (albeit for a short period of time) on a 2m pattern plane is power like you have never seen lol

The batteries on the other hand are a different matter altogether!

Hey Chad,talking about batteries. How are the new TP V2's running? How many flights have you had on them? Also do you have an opinion on the lasting power of the original Extreme's? Thanks, Mike