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is this right? trying to set up 6 servos to arduino uno... Answered

i am new at this and i suck!!! i am trying to run 6 hobby servos to my arduino uno- i am powering it with an external power source (12v adapter) and on my bread board all servo blk/red wires to the power + and the ground to -. The power on the bread board is going onto the vin diode on my arduino, neg to the ground on my arduino and all the other color wires from the servos to the numbered diodes on the arduino. Is that right? every time i run it i get the "because a USB was drawing too much power from your computer" response.  i know the 12v is a bit excessive to power up the servos, but does anyone know a better approach this?

much appreciated
let me know



Is that your 12V source plugged into the Arduino?

6 servos is a bit much for the arduino to handle even when connected to an wall adapter. At most the arduino can deliver about 1A, but the board itself is using some of that power. What you need is an actual external power source. One that is separate from the arduino and connect to the bread board. Just make sure you have a shared ground. Meaning connecting the ground from the arduino to the ground of the external supply. Also make sure you use a 5V supply unless the servos are 12V. Otherwise you'll burn out the servos.

thanks a bunch mplichfamily!!!

yes the 12v source is plugged into the arduino- is that not good?

i will take on that approach-a separate power source(5v) from ardruino > connected to the breadboard and shared ground from the arduino/external supply

must be 5v, i think the servo voltage are about 4.8 - 6 v


is a 21 channel servo driver. You should be able to talk to ie via the Ic2 connection - A picaxe does this easily.

I would expect each output to be able to drive an individual servo the electrical signal load is very low - the power for the servos should come from a separate source.

The 12V being plugged into the arduino is fine. There is an onboard voltage regulator that makes sure the arduino and anything connected to it is only getting 5V.

It sounds like he's attempting to backfeed the Arduino board via the shield pins !

The power on the bread board is going onto the vin diode on my arduino

You might very well have destroyed a.) Your computer port b.) Your arduino and c.) the servos, or any combination, or all of them.


Remove the 12V supply, and see if the arduino is still OK, and your computer can talk to it.


thanks for the response/reply. i checked my arduino and spoke to it. i think it's fine and i ran my servos individually- it seem to be okay. thanks again!!!

Your servos have 3 wires - + - an signal.

The + and - go to a power source and the signal to the micro. The power source and micro should have a common ground (-)


Much of the information you might want is here in these Picaxe manuals - cheaper and easier. the general principles are the same