Speed Control amp
 

This may seem like a silly question but i'll ask anyway. Whats the difference between a 10 amp brushless speed control for speed 400 and below motors compared to a 20 amp brushless speed control for speed 400 and below as well.?

I forgot to mention. also, how do you know how much amp you should use for certain electric brusheless motor?

RE: Speed Control amp
 

First, "Speed 400" motors are brushed motors. Mega does make brushless motors in a "400" size but they are not Speed motors. The amp draw of a motor depends on the pack voltage, prop size and pitch and gearing, if any. You can use an e-power spreadsheet to calculate the current. An ESC with larger capacity will cost you more and weigh a bit more.

RE: Speed Control amp
 

The difference is how many amps the ESC will handle before the "magic smoke" escapes :D (the ESC burns out )

I would STRONGLY suggest D/L Motocalc. It is free for a 30 day use, then you have to register it ($35 ). If you put the information into the program (plane, motor, ESC, prop, weight) , it will tell you how many amps the motor will be pulling at various speeds with various size/pitch props. Find the highest amp draw and add 5 amps to it (for a safety margin ). That is the size ESC you need.

If you don't want to use Motocalc/Electricalc, use the size motor, prop, battery and ESC suggested by the manufacturer (Many manufacturers state the sizes of all this equipment for AVERAGE performance )

I feel that if you plan to stay in electrics at all, you should have either Motocalc or Electricalc to obtain the best results from your plane.