Thanks for the info!
From what I gathered thus far, the Norwegian transformers are 230 volts ungrounded wye on the secondary and grounded through a "nullpunktsikring"
http://www.el-tjeneste.no/files/Brosjyre-Nullpunktsikring.pdfBasically its just a surge arrester with a fuse. If a surge occurs such as a primary going into the secondary, the arrestor shorts the transformer neutral to ground by blowing the internal fuse. Under normal conditions it remains isolated from ground. 230 volts is present between phases and no neutral exists for loads like in a 230/400Y network.
