The motor controller may be powered by a 9-volt battery or by supplying 12 volts DC into the power connector on the side.
For installing a battery in the motor controller click here.
Below is a picture pointing out the 12 volt DC connector on the side of the motor controller. This is where you would plug in a 12 volt DC power source. The center pin is positive (+) for this connector.
The motor controller is turned on and off with the power switch on the side as shown below.
