A lot of the 'T' plugs & sockets similar to the NEMA 2-20 pattern have found their way onto caravans & campervans for 12VDC power. The packet for the plugs rates them as "32V @ 15A". These plugs are also rated for 110VDC. The words 'extra low voltage' are marked on the plugs, matching extension cord sockets & surface sockets.
There are a couple of other plugs that are a mystery to me. In Australia, one manufacturer (Clipsal) offers a 2 pin parallel plug the same as a NEMA 1-15P configuration. It is rated at 250VAC @ 10A. I guess this was for electric clocks that were connected onto lighting circuits. This plug does fit into a NEMA 5-15R socket.
The second mystery plug/socket combination are the 3 pin plugs with two round pins (for active & neutral) & a flat earth pin. These are rated at 110V @ 10A. These are also an Australian made device. How much 110V gear made it into Australian homes to warrant manufacture this pattern of connector?. (I can get photos if people are curious on these connectors)
Finally, I have measured a three pin socket to see if the ones used in Australia, New Zealand, New Guinea & other South Pacific countries are the same dimensions as the NEMA 10-20R shown in this post. The one pictured is bigger that our sockets in distance between pins & pin size.
