The calculator requires input values for: battery capacity (mAh), reserve (%) and average amp draw (A).
Battery Capacity: This value can usually be found printed on your battery. The greater the number, the more energy the battery stores. If the capacity is stated in Ah (amp hours) you can convert from Ah to mAh (milliampere-hours) by multiplying by 1000. For example 2.2Ah x1000 = 2200mAh.
Reserve: It is recommended practice to not discharge LiPo batteries below 20% of total capacity capacity during flight; this is known as the ‘80% rule’. To represent this in the flight time calculator, a default reserve of 20% has been set, but feel free to change it as you wish.
Average Amp Draw: To work out the value for average amp draw, you’ll need to know the all up weight (AUW) of your drone and relate this to thrust and amp values found in the datasheet for your motor/prop configuration. The idea is to work out how many amps your multirotor will draw to maintain a stable hover (note we are taking a stable hover to represent average flight). For example, if your quadcopter has an AUW of 2kg, each motor will have to produce 500g of thrust in order to hover. If each motor draws 4amps to produce 500g of thrust, then your average current draw will be 16amps.
FORMULA: Watt hours (Wh) = Cell Count x Nominal Voltage x Capacity (Amp hours (Ah) |1 Ah = 1000 milliampere-hours (mAh))
