As far as New Zealand goes (and Ray might remember these) there were tables in the ECP (Electrical Code of Practice) 28, for the installation of cables, with a maximum length given for 5% voltage drop in a given run.
We have a test here in NZ, called an Earth-Loop Impedance test, that tests not only the connections to your panel, but back to the transformer.
It gives you a reading of the total impedance of the total loop, from that, you can measure your supply voltage and find your fault current.
Fault currents as mentioned above, are in the order of kilo-amps.
I did a test the other day at work and found that a simple fault will cause 250,000A, flow through cords and the like, if a breaker does not trip.
The Sub-station(66kV) is just over the fence, with a tranny just out the door (11kV/400V).
{Message edited for 2 typo's}
[This message has been edited by Trumpy (edited 11-02-2006).]
