Article Great Planes Electrifly Ammo 4300kV Motor & 2s 1500mAh LiPo Review

[dtknowles]

Near the beginning of the section on the Electrifly Lipoly pack you indicate that the pack is good for Speed 600 applications, I expect that you meant Speed 400. Also talking about the pack and its charge connector, safety circuit. You wrote "This very lightweight circuit stops charging the battery if the voltage reaches more than 4.2v per cell." It would be better if the truth was "it stops charging the battery if the voltage reaches more than 4.2 volts in either cell ." You know, to prevent damaging a cell in an unbalanced pack, do you know if this might be the case. Another curious thing is that when you tested the motor battery combo the 10 x 4.7 and the 11 x 4.7 prop drew the same current, whats up there? Finally for the 13 x 6.5 prop you said "Motocalc projects static thrust with this setup to be ~24.5 oz. Talk about a Yeeha! experience! The most powerful setup, and of course my favorite!" but you indicated that the 11 x 4.7 was projected by Motocalc to produce 27 ounces of thrust. That is more thrust as lower currents for longer flights I would be inclined to pick the 11 x 4.7 or the 12 x 6 prop for better thrust and less stress on the motor and pack. Did the 13 inch prop produce better flights in real world testing.

Thanks for writing the article.

Tim Knowles

[sloppytypist]

Great article. I had been hoping for a reveiw of this product. Do you know if these are the second generation of "Chile Pepper" motors? This first run had some problems, but at $69 and generation II, they would be an excellant value. Thanks agian for the write up.
Sloppy

[FLYWINGFAN]

Originally Posted by dtknowles

Near the beginning of the section on the Electrifly Lipoly pack you indicate that the pack is good for Speed 600 applications, I expect that you meant Speed 400. Also talking about the pack and its charge connector, safety circuit. You wrote "This very lightweight circuit stops charging the battery if the voltage reaches more than 4.2v per cell." It would be better if the truth was "it stops charging the battery if the voltage reaches more than 4.2 volts in either cell ." You know, to prevent damaging a cell in an unbalanced pack, do you know if this might be the case. Another curious thing is that when you tested the motor battery combo the 10 x 4.7 and the 11 x 4.7 prop drew the same current, whats up there? Finally for the 13 x 6.5 prop you said "Motocalc projects static thrust with this setup to be ~24.5 oz. Talk about a Yeeha! experience! The most powerful setup, and of course my favorite!" but you indicated that the 11 x 4.7 was projected by Motocalc to produce 27 ounces of thrust. That is more thrust as lower currents for longer flights I would be inclined to pick the 11 x 4.7 or the 12 x 6 prop for better thrust and less stress on the motor and pack. Did the 13 inch prop produce better flights in real world testing.

Thanks for writing the article.

Tim Knowles

Yes, I meant 400, I think Electrifly lists it as 600, and the editor assumed I made a typo and changed it. Really however, it is not capable of 600 amp draws.

I was really stumped by that 10x4.7/11x4.7 amp draw anomaly as well. I tried it a couple times and got the same each time. I am going to do it again next time I have a chance.

Thank you for bringing the voltage limiting to my attention, it was poor wording on my part. The circuit does limit each cell at 4.2v, not overall pack voltage.

The 27 oz static on the 11x4.7 was projected for 3s lipo, all the numbers I real world tested are from 2s. The 13x6.5 had the best inflight performance, the 12x6 was pretty good as well.

Sam

[FLYWINGFAN]

Originally Posted by sloppytypist

Great article. I had been hoping for a reveiw of this product. Do you know if these are the second generation of "Chile Pepper" motors? This first run had some problems, but at $69 and generation II, they would be an excellant value. Thanks agian for the write up.
Sloppy

Hey Sloppy,
They both use the same wind technology, however they are not the same. Reports are, the Chili's are handmade and the Ammo's are 5 mm shorter and mass produced. Whatever the case, the Ammo sure has good performance, and good price.

Sam

[FLYWINGFAN]

To everyone else,
Please, if you have any comments or questions chime in! I welcome any and all feedback, etc.

Sam

[dtknowles]

Sam

I am glad to hear you were not responsible for the 600 400 snafu. It looks like the article has been corrected. 10x4.7/11x4.7 anomaly could just be the props aren't really pitched the same. I asked about the "safe charge circuit" because I can't seem to find out about it and what you discribed before did not seem much of an improvement. I reread the 11x4.7 prop stuff and I see the 3s this time.

Tim

Originally Posted by FLYWINGFAN

Yes, I meant 400, I think Electrifly lists it as 600, and the editor assumed I made a typo and changed it. Really however, it is not capable of 600 amp draws.

I was really stumped by that 10x4.7/11x4.7 amp draw anomaly as well. I tried it a couple times and got the same each time. I am going to do it again next time I have a chance.

Thank you for bringing the voltage limiting to my attention, it was poor wording on my part. The circuit does limit each cell at 4.2v, not overall pack voltage.

The 27 oz static on the 11x4.7 was projected for 3s lipo, all the numbers I real world tested are from 2s. The 13x6.5 had the best inflight performance, the 12x6 was pretty good as well.

Sam

[desire]

It would be nice to see rpm numbers for tese set ups.

[FLYWINGFAN]

Unfortuneately I did not have a tach, however I do have these constants from hobbico you can plug in to motocalc or similar and do you your own experimenting.

Ammo 20-4300
kV: 4300
resistance: 0.035 - 0.041 ohms
no-load current: ~1.1A.

Note: Please take any results from motocalc with a grain of salt. The numbers are generally good, but not exact

Sam

[qban_flyer]

Does anyone has and idea as to what size and pitch propeller to use with the 4300 direct drive with a two cell Li-Po? APC 4.75X4.75? 5X5? 6X4?

I'm planning to use it in a Lil' Rascal. If I can't get an answer in this respect, I have already spoken to the LHS to return it and all the Great Planes ancillary equipment bought along with it.

Great Planes has been of absolutely no assistance whatsoever in this respect. Matter of fact, I was told that it is entirely up top the end user as to what prop to mount on these motors when used as direct drive. (?) They are clueless when it comes to this issue! Can anyone believe that?

[FLYWINGFAN]

The Ammo 4300 was not really designed with DD in mind. The largest prop you can use without grossly exceeding the max constant current is a 4x3. That will give you a pitch speed of nearly 80 mph @ 9 oz of thrust and full throttle current of 12 Amps. Should turn your lil rascal into a rocket ship, assuming you can find a battery that will support that kind of current while still fitting in the lil rascal . IMO, you should gear it down to perhaps 2:1 or 2.5:1. Although, I suppose since the ammo is allready heavy for that little thing at 2 oz for just the motor, you're allready pushing your luck.

Sam

[qban_flyer]

Originally Posted by FLYWINGFAN

The Ammo 4300 was not really designed with DD in mind. The largest prop you can use without grossly exceeding the max constant current is a 4x3. That will give you a pitch speed of nearly 80 mph @ 9 oz of thrust and full throttle current of 12 Amps. Should turn your lil rascal into a rocket ship, assuming you can find a battery that will support that kind of current while still fitting in the lil rascal . IMO, you should gear it down to perhaps 2:1 or 2.5:1. Although, I suppose since the ammo is allready heavy for that little thing at 2 oz for just the motor, you're allready pushing your luck.

Sam

It is heavy at 2 ounces, though the Lil' Rascals I have seen have had a tendency to be a bit on the tail heavy side and to snap unexpectedly.

According to the G/P pamphlet, the AMMO 4300 can be used either way. Since they were not specific as to what size prop to use either way, I e-mailed them. Their reply was rather silly in its content. I already have a two Himax 2015 & one 2025 with the Himax G/Bs, so the AMMO 4300 is of no use to me in a gearbox.

I will return it to the LHS since they're willing to take it back. I'll get me with an AXI 2204/54 from them instead. It is lighter and will fit in the space nicely.

Thanks for your quick reply. It has been very helpful.

[FLYWINGFAN]

According to the G/P pamphlet, the AMMO 4300 can be used either way. Since they were not specific as to what size prop to use either way, I e-mailed them. Their reply was rather silly in its content. I already have a two Himax 2015 & one 2025 with the Himax G/Bs, so the AMMO 4300 is of no use to me in a gearbox.

Technically, they are right, its just that the applications for DD are very limited. The AXI will be a much better option.

Sam