Amp usage in bench test vs flight?
« on: February 19, 2016, 02:06:40 pm »
Hello
Does a motor draw more amps when bench tested compared to a punch out in flight? Im a bit worried becouse the manufactuer states that the motor draw 35 amps with 6045 props att fulll trottle with 1100g of lift, will they draw the same in actual flying at full trottle?

Re: Amp usage in bench test vs flight?
« Reply #1 on: February 19, 2016, 02:58:45 pm »
Yes more on the bench. No probably not. Thoes are usually static thrust numbers.  So not moving. The load on the prop motor and esc will lessen as soon as it is spinning. But the second you punch you get a spike in Amps then it goes back doen
« Last Edit: February 19, 2016, 03:26:19 pm by NicholasDavid »
5" alien 4s 596grams with battery and GoPro FPV
Lantian LT210 4s 604grams with batt and GoPro FPV
GE X220 4s 6" 513grams with batt and HD cam FPV
Homemade acro X copter. 6" 4s - like a warpquad LOS

Mateusz

  • *
  • 808
Re: Amp usage in bench test vs flight?
« Reply #2 on: February 19, 2016, 03:08:43 pm »
Hello
Does a motor draw more amps when bench tested compared to a punch out in flight? Im a bit worried becouse the manufactuer states that the motor draw 35 amps with 6045 props att fulll trottle with 1100g of lift, will they draw the same in actual flying at full trottle?

Normally you don't fly 100% throttle all the time. I suggest checking if you don't exceed power rating with http://www.ecalc.ch/xcoptercalc.php which can give approximate rough numbers.
If your ESC are rated 20A that usually means continuous current and they can take more in bursts. However you would need battery that can deliver that much.
If your battery is 45C rated and 1800mAh that means 1.8A * 45C = 81A at most of continuous current (usually its a bit less). If you draw more than that, either battery will not be able to deliver that much, or deliver it in burst. For more current you need higher discharge batteries. So with that battery given that all 4 motors drain same amount of current, you would get 20.25A per motor max. Props 6045 for a 250-290 sized quad are pretty big I have to say.

Re: Amp usage in bench test vs flight?
« Reply #3 on: February 20, 2016, 09:17:11 pm »
great, thanks for the answer guys. 6045 props and 1100grams on a 250 is crazy but its gonna be cool :) I got the Little bee 30A and DYS 2205-2700kv with 6045 bullnose. zmr250 :)