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How do I choose proper power supply for my ESC Answered

Hi, I am very new to this, I apologize if my question is too stupid :)

I bought a brushless motor:


(I can't find proper specifications, so I am not sure what is the voltage for this, but somewhere on the internets it was mentioned that this model needs 11.1Voltage, and 15-25A or 30A max. (not sure how to check if that's accurate, the motor is RS 2212-920kv)

I also bought an ESC (I hope it's correct one...)


it says 30A on it. So seems legit to me.

Usually they power this setup with batteries. but I want to use a power supply to power this from 220v outlet.
I have some power supplies at home rated 2A, which I am sure is not enough. so I assume I need to get a 12v 30A power supply. 

I am afraid though that my assumptions will get me to burn my ESC, which will cause another month of waiting for new one.

Would really appreciate some help. What power supply do I need? how many volts my motor requires? should I provide 30A?
does this kind of supplies even exist? 




All the help you should need.

the 920 kv indicates that you will get 920 Revs per volt. This is an indication of how powerful the motor is.

I would buy in future from a better source such as hobby king who will supply specifications for the motors you buy.

Your ESC isn't really big enough you need to exceed the max motor current by 10 to 15% as a safety margin. it will work but may go pop at max power.or under high loads.

I assume you building some kind of aircraft? or RC car - then your power supply will be a battery pack. Nominally a 3S cell Lipo will give you 10 to 12 volts. You will need a Lipo charger as well

A watt meter is a good instrument to have so you can check current and voltage passing through your motor and avoid burn outs.

tell us more about the application for a better idea of how to do it.

PC on a 3S cell your motor will turn at about 9200 RPM!

Thanks for the answer! not really making an aircraft, it is going to be a very simple "mini table saw to cut through PCB" I want to put a 50mm circular saw-blade on the motor, connect that to power supply and see if it can cut through a very thin PCB. So using battery will be unconventional, that is why I need power supply. I will also connect a servo tester to the ESC, to control the speed. (I am making my own servo tester for this application based on 555 timer ic)

helps if we get a better picture of your project!

Trouble will be the current your wanting - 30 amps is a LOT to expect from a table top power supply even at 12 volts.

A lead acid battery will last you a LONG time and is easily obtained and charged - Just leave a trickle charger on it all the time.

Your motor will probably not have the torque you need for a saw unless you gear it down. mainly because RC motors are built very lightly and intended for model use - high RPM low torque applications.

However you won't know until you try.

Good luck.

Got it! I was excited to do this after this: https://www.youtube.com/watch?v=IUK9CEJS_u0 (and this guy did use battery, but I thought the idea of using batter kind of sucks, all because I didn't knew I need so many amps) Anyway it seems for me, it will be less of a headache to actually get just standard 775 DC motor for the job, 2 amps will be more then enough for it.

If everything works on 12V an old ATX power supply from PC should do the trick.

No, your assumptions are valid. You need a 360W power supply.