That's not possible where i live (Sweden) ? The power companys cable into the building must have some kind of ground ? It's either a combined PEN ground/neutral + screen or only the screen if its the kind of cable where the screen is designed with sufficient cross section to also be the ground/neutral conductor.
So the cable can have three phases and a thick screen.
Ground/Neutral is then split to separate Neutral and Ground in your house. You notice i
You should really not do this yourself.
Sorry for the Swedish in this simplified picture the fuses for individual groups are left out!
Example is just the residual-current circuit breaker or what you call your earth fault device in English ?
PEN=Protective Earth and Neutral
PE=Protective Earth.
In your house the 230VAC stuff outlets etcis connected to one of the phases L1,L2 or L3 and N via its respective fuse.
Your 3 phase 400VAC appliances like ovens water heaters etc uses L1,L2,L3 or possible just between two legs for example L1,L2 to get 400VAC
View attachment 116141
I left out a case which is very unusual for residential situations in my part of the world.
When there really is no neutral point the power companies transformer is of for example D/d or Y/d winding type instead of D/y or Y/y.
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