Throttle End Points
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Sure. kv refers to how many rpm a motor spins per volt. If a motor is 1000kv, on 12V it spins (theoretically) at 12000rpm.
No. It matters according to the type of model (aerobatic, glider, slowflyer, multicopter) Multirotors generally work best with low Kv motors.
Could you provide a link to the motor? 4000 Kv is not enough to know if it will run on 10 Amps.
You have to pick a target end point - what type of plane are you selecting a combo for, and how heavy is it?
Matching a power system stems from this information, as you then (usually) pick a motor that has the thrust (in grams or ounces) and builds the speed that flies the plane. Generally, alongside a motor's thrust specification, it will say what props were used in test to achieve this, for example motor A produces X grams of thrust with an 8040 prop. It will also say what the maximum Voltage for the motor is, or at least the number of cells a battery can be e.g. 11.1V or a 3s LiPo battery. It should also say how many Amps were drawn using this prop. You then choose your speed controller to be able to deal with at least 25% more Amps at the motor's Voltage.
Then you choose your battery based on the information you've derived above. If your target thrust and speed is achieved with a motor of X cells, then you use a battery matching the number of cells. If your motor draws Y Amps, your battery needs to be able to discharge that number of Amps safely. LiPo batteries have 2 ratings on them - a capacity rating eg. 1500mAh, and a discharge rating eg. 20C. The number of Amps that can safely be discharged from the battery is calculated by multiplying the Ah capacity (ie mAh/1000) by the discharge rating. For the numbers above (1500mAh and 20C), you can safely discharge 30A. However it's good practice to also pick a battery that can discharge at least 25% above the motor's max Amp draw, similar to the ESC. This way it will be less 'stressed' and will last longer.
This stuff is often very confusing for newcomers. People on this forum would be more than happy to recommend power setups that we know/use for similar planes until you get the hang of it.
Matching a power system stems from this information, as you then (usually) pick a motor that has the thrust (in grams or ounces) and builds the speed that flies the plane. Generally, alongside a motor's thrust specification, it will say what props were used in test to achieve this, for example motor A produces X grams of thrust with an 8040 prop. It will also say what the maximum Voltage for the motor is, or at least the number of cells a battery can be e.g. 11.1V or a 3s LiPo battery. It should also say how many Amps were drawn using this prop. You then choose your speed controller to be able to deal with at least 25% more Amps at the motor's Voltage.
Then you choose your battery based on the information you've derived above. If your target thrust and speed is achieved with a motor of X cells, then you use a battery matching the number of cells. If your motor draws Y Amps, your battery needs to be able to discharge that number of Amps safely. LiPo batteries have 2 ratings on them - a capacity rating eg. 1500mAh, and a discharge rating eg. 20C. The number of Amps that can safely be discharged from the battery is calculated by multiplying the Ah capacity (ie mAh/1000) by the discharge rating. For the numbers above (1500mAh and 20C), you can safely discharge 30A. However it's good practice to also pick a battery that can discharge at least 25% above the motor's max Amp draw, similar to the ESC. This way it will be less 'stressed' and will last longer.
This stuff is often very confusing for newcomers. People on this forum would be more than happy to recommend power setups that we know/use for similar planes until you get the hang of it.
Sure. What sort of plane is it? High, mid or low wing? Is it meant to go fast or slow?
That sounds about right. Remember to balance the plane before you fly it. As a rough guide, aim for 1/4 of the wing chord from the leading edge of the wing where it joins the fuselage.
If your plane can handle the weight, of course!
Yep. The 25% above max Amp draw of the motor for the battery is a minimum. There's no maximum. The higher the discharge capacity of the battery, the less 'stressed' it is delivering the power and in theory will last longer, and deliver better performance (by holding the pack voltage and therefore rpm higher throughout the discharge).
And the airframe can carry it. Yep.
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