Electric Beginner Questions
 

What's the difference between an ESC and a BEC?

What is a "brake" on a speed controller?

Do all Electric Aircraft Motors operate on the same voltage?

How does one size the BEC amps requirement?

Thanks in advance!

Tom

Electric Beginner Questions
 

Here we go:

ESC: Electronic Speed Control (Contols power to motor)

BEC: Battery Eliminator Circuit (Supplies power to the reciever)

Q:"What is a "brake" on a speed controller?"
A: A brake on the ESC stops the prop from spinning when the motor is off. This does two things: it allows folding props to fold, and reduces the likelyhood of breaking a fixed prop.

Q:"Do all Electric Aircraft Motors operate on the same voltage?"
A: No the voltage is dependant on how-many/what size the batteries are in you battery pack.

Q:"How does one size the BEC amps requirement?"
A: The current required of the BEC is dependant upon what size/how many servos you are running.

Cheers,
Grant

Answers:
 

Ane "ESC" is an Electronic Speed Control. You need one to allow your electric motor powering your plane to be throttled, IE operate at less than full power when you command it to. They operate by switching the voltage on and off at a high rate. You can hear a distinctive whine when they are operating that is a result of this pulsing.
Some ESC's incorporate a "BEC" or Battery Eliminator Circuit. This taps power off the motor battry pack to power the reciver and servos of the plane. Allows you to save weight by not carrying a seperate rcvr pack. Can only be used with a certain range of cells, greater than 5 and 10 or less.
Some ESC's incorporate a brake that stops the motor instantly when you throttle all the way back. Its used with folding props to assure a clean fold.
Motors can be made to run any voltage (# of cells), the same motor can be made in different "winds" to suit the number of cells used. I have seen cell count from 1 to 42. Quite a wide range of voltage. The cell count can be experimented with on a given motor to achieve desired performance.
Sizing a ESC depends on the motor wind and type, and the number of cells used. You might want to consider an existing combo that is known to work .
If your ambitious, you can obtain free software on the net , such as Pcalc, that will predict the amps and watts and other important factors. You need some technical info on your chosen motor to make these work though.