Arduino on BEC with multiple servos

Other Hardware Motors, Mechanics, Power and CNC
1

Hey!

I'm new to Arduino and electronics altogether so go easy on me.

Here's what I want to do:

LIPO battery -> ESC/Switch Mode BEC running motor -> Arduino. The arduino then needs to have 5 servos and lets say 3 sensors on it. My question is, how can I determine if the arduino will be getting enough amps from the BEC to run all my components? I assume there must be some math to work that out.

I'm not sure how to find out how many amps the BEC can deliver (ESC is rated to 40A if that helps) and then I assume there must be some limit of what current can go through the 5V pin on the arduino?

Thanks!

2

That is trial and error, the wrong way to go. Sum up the amps needed and get BEC that delivers that. Then read the BEC datasheet.

1 Like
3

You should NOT power the servos from the arduino.
Your servos should be powered directly from the BEC.
If your other sensors just use a few mA @ 5V then you can connect them to the arduino 5V output

1 Like
4

Thank you, what's the easiest/best way to split the BEC power? Can you get plugs for this kind of thing?

5

What kind of thing?

6

To split power from a BEC to different things. The plug coming off the BEC is one of those plugs servos use (don't know the name sorry), so I need to split that into two. Or am I just going to have to solder.

Also for the battery I get, if I get something with more amps than I need but correct voltage for the ESC, thats fine, correct?

7

That connector is for connection to an RC receiver for controlling the speed of the motor.
It may only supply a few hundred milliamps

8

That connector came with the airframe I'm using, as did 5x 9g servos, so I would assume that the amperage is high enough to run those components. Question I had, which I think you answered, is whether the arduino output pins can pass that amperage on, and the answer is no, correct?

9

Correct.
Some of those little 9g servos can draw up to 500mA. That alone is too much for most arduinos, UNO, mini etc.

10

Ok cool. So I'll figure out a way to nicely split the power off the BEC towards the arduino and each servo in parallel.

So theoretically, the battery I choose needs to match the voltage that the ESC is designed for, but the amps can be whatever, provided they can cover max draw of servos, motor and arduino correct?

Thanks for your help so far!

11

Hi, @snidge
Welcome to the forum.

Can you tell us your project?
This will help advise how you need to connect all this hardware.

Thanks.. Tom.. :smiley: :+1: :coffee: :australia:

12

True but you also want to consider how long the battery will last. If the motor draws 10A continuous then a 5000mA battery will only last 1/2 hour (5/10)

13

Awesome thank you

14

Thanks Tom!

The project is an RC plane that has a 40A motor and ESC/switch mode BEC and 5 9g servos already installed, and I'm going to use an arduino as a reciever with a few added modules like a GPS and LoRa receiver.

15

This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.