hawkman-RCU

are there any threads or sites that i can view which will help me to understand what all the numbers mean on motors and batteries.not new to flying just new to electric.i want to get into 3D foamies.torn between the sabre and the spider because they are not flat foamies.

thank you.

plkracer

Most motor's numbers are hard to compare. A lot are just reference numbers. Other numbers are the Kv rating, or the rpm per volt, or the amount of turns, winds, or poles. Turns are the amount of times the wire is wrapped around the pole. Wind is the strands in a turn, and a pole is the metal that the wire wraps around. When electricity is passed through the wires, the pole becomes magnetized, attracting the magnets on the armature, or case in an outrunner. Lipo numbers are compatable with all lipo's. 2s1p is a pack with 2 cells. They are in series. Each cell has 3.7 volts, so this pack is 7.4 volts. 2s2p is a 4 cell pack. It is 7.4 volts, but 2 are in parallel, so it has double the milliamp hours, "mAh." s is for series, and p is for parallel. The mAh rating is the amount of stored energy. 1500 milliamp hours will last roughly 1 hour at a 1500 milliamp draw. This is considering no loss in energy as it heads to the load. A 2000 mAh pack will last 1 hour at a 2 amp load, adn so on. So a 20 amp draw on a 2000 mAh pack will give you 1/10 of an hour, or 6 minutes. The "C" rating is the discharge capacity of the pack. 10C means that a 2000 mAh pack can be discharged at 10C, or 10 times 2000, for 20 total amps. 10 times 2000 is 20,000 mA, or 20 amps. 15C on a 2000 mAh pack is 30,000 mA or 30 Amp total draw. For a 3d plane, considering it is about 13-16 ounces, you will want a motor that will draw between 8 and 12 amps. You also need a brushless esc capable of powering the motor. For a battery, I would look for a 3s1p battery, with between 730, and 1200 mAh. Discharge should be 15C minimum for the 730, and you can go less, like 10C for the 1200. If you draw 12 amps, you will want more than 10C though, because the motor will be pulling all that the battery has. For optimal performance, you want the motor to draw about 70% of the total amp draw. For a 8 amp motor, 730 at a 15C rating is good, or a 900-1000 at 12C For the 1200 pack, you could go 10C. For a 12 amp motor, you will definitely want at least the 1000 mAh battery, at 15C or better.

perttime

The numbers in motor "names" are often quite useless, at least to a non-electric-engineer type.
Fortunately, a lot of motor manufacturers or dealers supply performance data that can give you a good idea of what to expect from a motor.

Some of the most useful kinds of information is actual test data with different propellers and batteries.
You want to know:
- weight
- useful prop sizes
- useful voltages ("V", how many cells in your battery)
- permissible current ("A", how fast you are emptying the battery)
- Power ("W", combination of the above)
- how much thrust you can get / how much speed you can get.

Here is an example for a motor that I am using:
http://www.airmedia.se/Typhoon-15-10-test.htm

hawkman-RCU

thank you for your response,now i need to do some study.thanks again. paul in phoenix.