Text only | Text with Images

RC India

RC Equipments => Electric Power => Topic started by: xxkrishxx on July 24, 2010, 10:01:54 PM

Title: Electrical Setup
Post by: xxkrishxx on July 24, 2010, 10:01:54 PM
Hi guys I need ur opinion for the following setup,whether Its suitable for a SPAD TRAINER plane of AUW of 800gm.

1.TowerPro Outrunner 2409-18 1000kv/180W
2.Turnigy 1300mAh 30C 3S  LiPo
3.Turnigy 25A ESC
4.HXT 900 servos
5.8x4E Propeller

Pls give ur suggestions friends..
Title: Re: Electrical Setup
Post by: anwar on July 24, 2010, 10:43:41 PM
Are you sure about the 2408-18 ?  I see 2408-21 and 2409-18. There are sometime significant differences in wattage on these motors for small changes in model numbers. 
Title: Re: Electrical Setup
Post by: xxkrishxx on July 24, 2010, 10:47:48 PM
Oh sorry its 2409 only..
Title: Re: Electrical Setup
Post by: anwar on July 24, 2010, 11:13:02 PM
There are two small variations or the 2409-18, but they are both quite close to each other in terms of wattage.  At about 180W, you can have a plane that is a trainer or one that does some aerobatics. 

Do not add weight (bigger batteries, etc) initially, you can do that after doing some initial testing with the smaller battery you mentioned.
Title: Re: Electrical Setup
Post by: Ashta on July 26, 2010, 05:07:51 PM
If u have 800 grams AUW, u need a min 150W of power in order to fly. So when you put a 8x4 prop on your 2409-18, just check and ensure that it is drawing a min of 15Amps at 10V or more.
In any case for an 800grams AUW, i feel that it is a bit marginal. Also some of the lipos, when rated for 30C, they will take only half or less to that in practice.. be carefull. For ex the 1300/30C, may be comfortble up to say 18A continous.




Quote from: xxkrishxx on July 24, 2010, 10:01:54 PM
Hi guys I need ur opinion for the following setup,whether Its suitable for a SPAD TRAINER plane of AUW of 800gm.

1.TowerPro Outrunner 2409-18 1000kv/180W
2.Turnigy 1300mAh 30C 3S  LiPo
3.Turnigy 25A ESC
4.HXT 900 servos
5.8x4E Propeller

Pls give ur suggestions friends..
Title: Re: Electrical Setup
Post by: dinil on July 26, 2010, 05:40:30 PM
for 2409-18t towerpro heres the tested data
http://www.headsuprc.com/servlet/the-1416/2409-dsh-18T--Outrunner-Brushless/Detail



but knowing just the wattage can we find the thrust
for example if  i have  a 100W motor what will be the thrust
Title: Re: Electrical Setup
Post by: xxkrishxx on July 26, 2010, 06:13:02 PM
Whether  1600mAh 2S1P 30C lipo n 10x5E propeller will be a good one?
Title: Re: Electrical Setup
Post by: dileepbalan on July 27, 2010, 07:37:20 AM
Hi Krish,

Could you please post the plan you are going follow? are you planning to design with coro?

Regards,
Dileep
Title: Re: Electrical Setup
Post by: anwar on July 27, 2010, 02:05:19 PM
Quote from: dinil on July 26, 2010, 05:40:30 PM
but knowing just the wattage can we find the thrust
for example if  i have  a 100W motor what will be the thrust

Many variables go into thrust calculation, and there are programs to do that, like in this thread below.

http://www.rcindia.org/electric-planes/estimate-electric-motor-and-prop-combo-calculate-thrust-watts-flight-time-etc/

Ultimately it is about using a wattmeter to be sure.
Title: Re: Electrical Setup
Post by: Ashta on July 28, 2010, 11:34:36 AM
as you can see an 8X4 prop can give you apprx 600 grams thrust. so it may be marginal for an 800 grams auw.
a rough calculation from watts to thrust ( very rough) is X4. ie 100 watts = 400 grams. for med KV motors like 1000KV to 1500KV

Quote from: dinil on July 26, 2010, 05:40:30 PM
for 2409-18t towerpro heres the tested data
http://www.headsuprc.com/servlet/the-1416/2409-dsh-18T--Outrunner-Brushless/Detail

but knowing just the wattage can we find the thrust
for example if  i have  a 100W motor what will be the thrust
Title: Re: Electrical Setup
Post by: Ashta on July 28, 2010, 11:36:14 AM
completely agree with Anwar esp since these chinese motors come with large variations.
Text only | Text with Images