I have no idea how to explain what you just asked so I’m going to describe how my setup is. In my case I have neutral screen cable going from the pillar at my boundary fence to my switchboard at my house. For a single phase supply it would be single core neutral screen. In my case it is 3 core neutral screen.
That cable connect to my meter in my switchboard I have a main switch, big fuses for the main and breakers which covers the single phase supply to my house. There is an earthing rod beneath that switchboard at the house as it is all outside.
From that switchboard going underground to my workshop is another neutral screened cable in my case 3 core neutral screen which goes to another panel in my workshop where there is a main switch and the breakers for my workshop. The workshop panel has its own grounding Rod. So I have a grounding Rod at my house for that panel and a grounding rod at the workshop for that panel but both are fed off the same supply.
You could I imagine have the earth for the outbuilding go back to the house but I didn’t do that in my case. I just went with what my electricians told me to do for my application
An equipment grounding conductor is different than a neutral. its sole purpose is to establish a low impedance pathway for carrying fault current to enable breakers to be able to clear the fault current by tripping and opening the circuit.
This low impedance pathway is established by bonding the neutral to the equipment ground at the main panel. this essential creates a line to neutral short when an ungrounded conductor contacts and shorts to a grounded object.
From elsewhere on the net:
What happens in OZ is similar to most of the world; the odd one is the US.
Power is distributed as three phase with 120 degrees between each leg or phase. It is wired in a star configuration with the centre point being neutral. Neutral is connected to earth at the generator and at other major distribution points, substations and switchboards etc. throughout the system. Hence it is call an MEN (multiple earth neutral) system.
The voltage between phases is root 3 times the voltage between a phase and earth, eg. 415 volt between each phase -- 240 volts between any phase and earth. (as Robert described)
It is simple, reliable and uniform thought out the country
At a venue power will be supplied at 415 volts 3 phase. 32 amp 5 pin sockets are the most common, and 240-volt single-phase sockets 10 or 15 amp sockets are also the most common.
The colours are green or green with yellow for earth. For single phase, blue is neutral and brown is active.
In three-phase configurations it should be the same but often confusion can arise with various colour coding in different cables resulting in neutral and active are transposed … so … always check, it does not happen very often but it does happen and you will get 415 volts out of a 240 volt power point!
Ummm the US has star wired electrical supplies. its technically called Wye. 208Y/120 and 480Y/277
Also the MEN system is used by most PoCos in the US on the high voltage side. My PoCo has a connection from neutral on the top of the pole to a ground rod at the base wherever there is a 3phase dip to a PAD transformer. So im not sure why youre saying the US is odd.
Also, prior to 2008, electrical systems in buildings had the MEN setup with a bonded neutral in every building with a subpanel.
But they changed this because they realized it created a potential for shock hazard should the neutral develop a bad connection.
The MEN setup should not be used on the load side of a meter past the main service panel or disconnect for this reason.
So before you call the US odd, you should understand why its done this way...
that has NOTHING to do with whether grounding electrodes were required and has nothing to do with the 2 rod exemption to the ohms test.
The 2008 code change had to do with bonding of the neutral in subpanels. this was done to get rid of the potential for shock should the neutral develop a bad connection
