Power distribution in Norway

[Merlion]

My apologies for posting in English here. My command of Swedish is what one would call non-existent

Can't find an equivalent Norwegian forum and international forums don't result in a satisfactory answer, so hopefully someone can help me with this:

I understand that the mains supply system in Norway differs considerably from most of Europe. Could someone clarify these.

- Most 3-phase supply is 3x230V without neutral?
- Do (some) homes get 3-phase supply or always just one single phase?
- How does the grounding in Norway work. Is this one transformer leg (delta) connected to ground (230,230,0 V with respect to ground) or Wye centre tap connected to ground (130,130,130V with respect to ground) or is this a so-called IT-system (floating) with (or without?) GFCI. If so how do residents monitor earth failures?

Thanks

[AndLi]

https://www.byggahus.se/forum/el/161444 ... refas.html (Which is in swedish too... )

They cant get only one phase, 230V is between two phases...

they seem to have booth systems, older 230Vx3 systems are IT with local ground connection.

In some newer areas they have 400Vx3 TN C-S

[danei]

I suppose that the normal supply are 3phase. 1Phase do not exists. Normal 230V outlets are 2phase.
There are no neutral in the grid. But I suppose that the center tap are grounded.
You could know that there also exits installations with 400V main voltage and neutral. As I understand most new installations are 400V

[Merlion]

Thanks, finally some satisfactory answers

They cant get only one phase, 230V is between two phases...

What I meant was of course 2 phases, so used to "single phase" for 3x400V+N systems.

[alexanderson]

Det norska systemet har även använts på en del platser i Sverige!
I USA användes två olika system för att få 117V i vägguttagen.
Vanligast 117-0-117V alltså 234V mittjordad.
Mindre vanligt 117/208V trefas.
För drift av större motorer användes 440V trefas.
Jämför med vad som förekom på svenska industrier förr. 500V för motorer och 127/220V för belysning.