I know what size wire a particular motor I want to run takes.  But I'm not sure how much larger I should size it due the distance the motor is from my power source.

Hypothetically, lets say the motor calls for number "10" wire.  At how many feet away from my power source do I have to start increasing the size of the wire?   Is there an incremental standard involved in this..... say for every 100 feet we need to increase the size of the wire a particular amount?  Is there a general rule like that?

thanks, gordon