bblaske

My Feedback: (2)

We have a Sim Prop 300 speed motor with 350 gearbox that's rated for 6 volts, but the recommended battery pack is for 8.4 volts, 600 mah. Also Jetti 110 speed control in the Fatty.
How come we're not buring out the motor?
What other battery voltages can we use?
Does Millamps affect the motor?
We're getting 2 min. or less flight time. What should we look for in trying to get longer flight time?

thanks for help

Direwolf

You *want* to burn out the motor?

I'm surprised your not burning out the ESC. If you're getting 2 minutes of flying time on 600mAh, that means the circiut is creating 18 Amps! of current. And you're using an ESC that is rated for 11 Amps of continuous current. Is the ESC getting really hot?

The capacitance of the battery (Amp*Hours) affects the maximum safe discharge current of the battery pack. This can affect motor performance, only if the battery's maximum discharge current is lower than the maximum current the motor can handle. In your case, it probably isn't. I think I can guarentee that if you keep running that setup as is, then you'll eventually burn out everything.

Usually the easiest way to increase flight time is to use a higher capacity battery (higher mAh). Be aware that this will also increase weight, which means that the motor will need to do more work to keep the plane in the air, so it may generate more current, which also increaces heat produced by electrical resistance. So, there's a whole bunch of things you need to optimize. If you go with a larger battery, you might consider using an ESC that can handle more current, or at least installing a good heat sink on the ESC to draw away the extra heat.

-- Brian

bblaske

My Feedback: (2)

Thanks for you answer on this. We're checking on the Jetti itself cause seems like we bought a complete package upgrade when we got the Fatty and perhaps my son gave the wrong info on Jetti. Hope he did !

bob in nc