Power supply for RC airplane components

Hello everyone.
I’m going to build an RC airplane.
I’m going to use a 3s LiPo Battery for the motor. (11.1V)
The other parts are an arduino nano, nRF24 (which needs 3.3V), and micro servos (need 5-7V).
Please suggest me best ways to power the airplane. Is it better to power the whole plane with the LiPo battery and use a buck converter for servos and a regulator For nRF? or is it better to power motor with LiPo and power the rest components with 1 or 2 Li-ion? Or use LiPo for motor and a buck converter for servos, and a li-ion battery for arduino and nrf24 (with a regulator)? Or any better suggestions? I don’t want to make the plane heavy, all parts without any battery will weigh about 700grams so it’s a light plane.

The Electronic Speed Control (ESC) that you use to control the motor will very likely have an Battery Eliminator circuit (BEC) incorporated in it from which you can supply the Nano and the servos. The NRF24s can also be powered with 5V via a board into which they plug, such as these NRF24 adapter

Which ESC do you intend to use ?

And the battery eliminator circuit in the speed controller is used to power the, typically 5V, radio control receiver in a standard setup.

UKHeliBob: The Electronic Speed Control (ESC) that you use to control the motor will very likely have an Battery Eliminator circuit (BEC) incorporated in it from which you can supply the Nano and the servos. The NRF24s can also be powered with 5V via a board into which they plug, such as these NRF24 adapter

Which ESC do you intend to use ?

I will use this ESC.

Well as It’s my first time building rc planes and even knowing about how they work, I didn’t know anything about BES, i think the ESC that I’ll use has BEC with max 5 amps, I think it will be more than enough for Arduino, nRF and 6 micro servos working together.

That esc you link to has a max rating of 3A which should be ok for the Arduino and the NRF24 unit.

5v straight from this to the Arduino Vcc and to an NRF24 adaptor (as would be recommended).

Servos need perhaps as much as 1A each so better to run the supply for them from the 3S via a converter of appropriate current rating.

What this may be is unknown as you do not say how many servos you are running.

Note that many servos will not tolerate voltages above 6V.

bluejets: That esc you link to has a max rating of 3A which should be ok for the Arduino and the NRF24 unit.

5v straight from this to the Arduino Vcc and to an NRF24 adaptor (as would be recommended).

Servos need perhaps as much as 1A each so better to run the supply for them from the 3S via a converter of appropriate current rating.

What this may be is unknown as you do not say how many servos you are running.

Note that many servos will not tolerate voltages above 6V.

Yes you're right, 3A, I said 5A by mistake. I'm going to use 6 servos, (this one) They are rated 220mA. So I think it is still okay to use all these servos, Arduino and NRF24 with the 5V 3A right?

SG90 servos have a startup current of 650mA (220mA is the normal working current). So you might get away with a 3A BEC provided not all of the servos are likely to be working at once. So what are the 6 servos for? 2 x aileron, 1 rudder and 1 elevator is conventional. What about the other 2?

Steve

slipstick: SG90 servos have a startup current of 650mA (220mA is the normal working current). So you might get away with a 3A BEC provided not all of the servos are likely to be working at once. So what are the 6 servos for? 2 x aileron, 1 rudder and 1 elevator is conventional. What about the other 2?

Steve

Well I want to use flaps for softer landing and easier take-off, so these 2 servos will be idle most of the time. And I guess arduino and nrf won’t draw more than 200mA. So 4*650=2700, and 2700+200=2900mA. So it’s less than 3A. But I’m not sure if the BEC can provide about 2,9A continuously or not? Any absolute answer or suggestions? Or maybe I’d better to test with the BEC and if it couldn’t provide enough current, I use a buck converter? Or is it a high risk task and may burn the BEC? The reason that I prefer using BEC is 1st a bit simpler circuit and less wires and components, and 2nd reason is having as light weight as possible.

If this your first venture into model Aeroplanes then I would suggest : - join a club - get some experience flying something with conventional RC . - then think about building your own control system .

It will be hard enough to learn to fly without all the variables of home built gear . Most small models don’t use flaps, I was flying for several years before I started building in flaps ( which incidentally usually need trim compensation of the elevator ).

Not trying to be negative here , but if you start with something complex , that someone else can’t fly , you may well get very frustrated and give up .

hammy: If this your first venture into model Aeroplanes then I would suggest : - join a club - get some experience flying something with conventional RC . - then think about building your own control system .

It will be hard enough to learn to fly without all the variables of home built gear . Most small models don’t use flaps, I was flying for several years before I started building in flaps ( which incidentally usually need trim compensation of the elevator ).

Not trying to be negative here , but if you start with something complex , that someone else can’t fly , you may well get very frustrated and give up .

Thank you for your reply. Unfortunately there isn’t any club in my city, if there was any, I would get some experience there. But to have a general knowledge about rc planes and flying them, I watched many YouTube videos and read many articles, and I installed a rc plane simulator on my iPad to learn basic controls, the app simulates very well. And for building my own, at first that I decided to build one I had now idea what to do and where to start, I started a topic in this forum and someone told me about RCGroups, then I visited this website and flitetest and read and watched a lot, and for my first experience of building, I found this simple and complete guide to design and build a trainer model.

erfan_m14: Thank you for your reply. Unfortunately there isn’t any club in my city, if there was any, I would get some experience there. But to have a general knowledge about rc planes and flying them, I watched many YouTube videos and read many articles, and I installed a rc plane simulator on my iPad to learn basic controls, the app simulates very well. And for building my own, at first that I decided to build one I had now idea what to do and where to start, I started a topic in this forum and someone told me about RCGroups, then I visited this website and flitetest and read and watched a lot, and for my first experience of building, I found this simple and complete guide to design and build a trainer model.

I can foresee several (many) crashes and engrained bad flying habits ahead.

Seen it many times before.... :o :o

This is a topic I know something about:) I used to instruct at a local club. My first suggestion is to NOT use an arduino on any kind of a trainer plane. Purpose designed RC gear is inexpensive and plug n plug. If you must teach yourself, buy a purpose built foam trainer. Nothing fancy. You will be gluing it back together quite often. Join a good RC forum like rcgroups.com