wa2ise,
A funny thing about the AS/NZ plug with the round earth pin.
They were originally designed for dedicated circuits, like computers and so forth (to prevent things like heaters and vacuum cleaners being plugged into them).
So far, I've never ever seen one installed in any commercial building yet.
When I worked in port Hedland WA back in the 70's these plug/sockets were in use in one of the laboratories.
Round the mining site special 110v plugs were used that had round active pins (2 of them 55v each leg) and a flat earth. Problem was the switches were single pole so you always had 55v even when off.
Believe it or not it was possible to force a 240v plug into a 110v trailing socket. Useful if you had to take the oscilloscope out on site. Just had to make sure the voltage selector was put back to 240V afterwards.
