RC India

RC Baazar => Wanted => Topic started by: roby on May 16, 2014, 01:45:30 AM



Title: Low kv motors in bulk very urgently
Post by: roby on May 16, 2014, 01:45:30 AM
Want low kv motors preferably emax or better


Title: Re: Low kv motors in bulk very urgently
Post by: roby on May 16, 2014, 01:46:26 AM
300-600kv will be fine


Title: Re: Low kv motors in bulk very urgently
Post by: KineticHobbies on May 16, 2014, 04:32:52 PM
KV is too general dear. Specify motor wattage/thrust/size.


Title: Re: Low kv motors in bulk very urgently
Post by: roby on May 16, 2014, 04:56:57 PM
atleast 2kg of thrust per motors required, plus motor should be suitable for multirotors


Title: Re: Low kv motors in bulk very urgently
Post by: satyagupta on May 16, 2014, 07:06:12 PM
4cell or 3cell?


Title: Re: Low kv motors in bulk very urgently
Post by: roby on May 16, 2014, 07:56:22 PM
Any would work, I just need the required thrust...
I'm not good at specs, but 4 cell preffered


Title: Re: Low kv motors in bulk very urgently
Post by: satyagupta on May 17, 2014, 08:08:03 AM
soon i am getting a motor which can generate upto 2kg of thrust with 11 inch props and 4 cell lipo


Title: Re: Low kv motors in bulk very urgently
Post by: v2 eagle on May 17, 2014, 08:46:30 AM
Satya ji,

What could be the ESC needed for them interms of AMPs.

Ashok.P


Title: Re: Low kv motors in bulk very urgently
Post by: KineticHobbies on May 17, 2014, 10:56:58 AM
atleast 2kg of thrust per motors required, plus motor should be suitable for multirotors

Too low KV will demand large propellers and big batteries. 650 KV or less KV motors will need about 13-14 size props and may be 5S batteries.

Here's a good motor than can generate 2KG thrust with 4S and 12 inch prop:
http://www.kinetichobbies.com/index.php/motors/outrunner/motrolfy-dm2820-kv950.html (http://www.kinetichobbies.com/index.php/motors/outrunner/motrolfy-dm2820-kv950.html)



Title: Re: Low kv motors in bulk very urgently
Post by: Rcproduct on May 17, 2014, 01:28:25 PM
Hi,
roby

Can you tell me your budget so i can arrange for you..in lower cost.

THanks

 :hatsoff:


Title: Re: Low kv motors in bulk very urgently
Post by: roby on May 17, 2014, 04:28:01 PM
2000-2500 per motor sir :)
thanks for your response


Title: Re: Low kv motors in bulk very urgently
Post by: roby on May 17, 2014, 04:31:04 PM
or maybe i can stretch a bit, but i need 2kg of thrust ideally at its max efficiency.


Title: Re: Low kv motors in bulk very urgently
Post by: nikkybox on May 18, 2014, 07:50:57 AM
Roby.... you need to read up a bit about motors... particularly in multirotors.. Low Kv in multirotors is generally 400 below..
I see a lot of non scientific information floating around in this forum..  There is a direct relation between power motor kv and prop size. Higher voltage reduces your motor amp intake as it increases the kv per volt which now brings you to a smaller prop on the same motor.
I would go on a low kv motor when I need to use larger slow fly props or bigger system which can lift more. There I will go straight for 6 cell batteries... They are standard.


Title: Re: Low kv motors in bulk very urgently
Post by: nikkybox on May 18, 2014, 07:52:05 AM
Also. With multirotors. I will never go with cheap motors... The price difference is not much.


Title: Re: Low kv motors in bulk very urgently
Post by: satyagupta on May 18, 2014, 10:19:52 AM
Its under 25A i will be putting those on website today.


Title: Re: Low kv motors in bulk very urgently
Post by: SideWinder on May 18, 2014, 04:14:40 PM
Higher voltage reduces your motor amp intake as it increases the kv per volt which now brings you to a smaller prop on the same motor.
 
Can you exactly explain what were you trying to say there? Kv remains the same but RPM increases with every Volt applied to the same motor because Kv is explained as number of revs per volt. And current intake would increase on the same motor if you increase the voltage with the same prop. As for amp draw, other than Kv it also depends on the design and quality of the motor itself.

And usually people who reduce size of the prop while prepping up cell count do so because they are already using max prop size at low voltage, so reducing it by an inch or two, at higher voltage makes sense and prolongs life of the motor. And there is increase in thrust but at the cost of efficiency. Otherwise you can use the same prop size with different cell configurations suggested if AUW is optimum.

Selection of Kv not only depends on AUW but also on application. Usually low Kv motors are used in multirotors to lift more weight which is usually Aerial Photography equipment, where in stability(attitude and vibrations wise) is important. A flyer who wants to perform stunts would like high Kv motors because of the power they are able to deliver, but they are not very suitable for AP platform without an efficient gimbal. And if I want to reduce the size of the multirotor, low K's dont fit in.

I see a lot of non scientific information floating around in this forum.
Reason for that is multirotors are gaining popularity so are the number of users, hence we have a couple of self declared pundits who in their zeal to help others often serve limited data or sometimes corrupted data. I dont blame them completely, because it is the duty of the member/OP or anyone for that matter to seek;finding and comparing more data available online(not only forums) before arriving on any conclusion.