Again,Australia is a big place,just like Canada!
I'm fairly sure that in WA you need an Electrical licence anywhere in the state to do any wiring directly connected to the mains.
I guess if it is on your own property,running off your own power supply,they might not have a say,but your insurance company would!
I was a Radio Transmitter Tech for years,working for the Commonwealth.
As the sites were Commonwealth property,the state did not have authority,so we could work on high voltage equipment.
Commercial radio & TV sites had a similar,if de facto situation,because of the requirement of a Commonwealth licence for the Technical staff working there.
In both cases,major Electrical installations as distinct from the wiring & repair of transmitters were normally done by Electricians.
In emergency situations,however,if it was in the building you fixed it.
In the mid '80s the Commonwealth backed away from its previous attitude & about the same time, the WA State Electrical licensing authority suddenly discovered that Technicians didn't all just work on transistor radios,& actually fixed equipment with HT voltages of around 10kV DC(Shock!,Horror!).
They then started yelling that we had to have Restricted Electrical Licences.
I've got one,which in effect, allows me to do what I've been doing for 40 years.
73,VK6ZGO