Wiring and distances between LED drivers and fixtures do not have set requirements, but circuits are generally designed so that the voltage drop due to wiring is no more than 5% of the total circuit voltage.  As stated in Ohm’s Law (V=I*R), current conducted by a wire is proportional to the voltage drop across the wire.  A wire’s gauge, length, and composition affect the resistance of the wire, and hence affect the voltage drop across the wire when a current is applied.  There are only two options to reduce the resistance of a length of wire, namely by increasing the wire’s gauge or decreasing the wire’s length.