Grounding conductor connected to grounded conductor

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Baluncore said:
Back to the topic, your argument that Norway needs the IT system because it is largely made of rock
Well, all countries are based on rock. The thing about Norway is that the last Ice Age scoured bedrock bare (my theory is that Denmark is largely made up from those masses the ice removed from Norway).

And - my last comments on power distribution:
  • The town of Hammerfest (very far north) got electric power installed very early. The reason: Midnight sun in the summer but midday darkness in winter. The sun is below horizon from about 20th of November until about 20th of January.
  • This may be an urban legend, but anyhow: When the town of Trondhjem was due to be electrified, there was a broad political discussion on whether to go for 115V or 230V. A political resolution was to go for the middle - namely 150V. Fortunately, the politicians did not have the last word...
 
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Svein said:
This may be an urban legend, but anyhow: When the town of Trondhjem was due to be electrified, there was a broad political discussion on whether to go for 115V or 230V. A political resolution was to go for the middle - namely 150V. Fortunately, the politicians did not have the last word...
Go for the middle voltage that no-one uses! Talk about sitting on the fence... A perfect place to quote Jim Hardy:

“The grid is a machine and when politicians mess with machinery they generally do it harm”.

Source https://www.physicsforums.com/insights/interview-instrument-engineer-jim-hardy/
 
The issue of grounding for human / pubic safety is completely "political" - or relating to the Public Affairs. In the USA, OSHA, NEC (NFPA) and other agencies regulate these systems, they exist because the people wanted it.

Originally most if not all systems were ungrounded, there are still some legacy delta fed systems in the USA. In these system the priority was given to up-time or reliability, and to build in human safety was an added cost and complexity. IMO - human life is WORTH more today & we pay more to protect it. Years ago it was accepted that people died in the workplace or on the farm. We had 12 year olds working in coal mines and tanneries.

If the powers that be in a region did not want to pay the price to change or upgrade the system to protect human life, they did not. In some cases, they chose to use other protections, for example behavior (not good protection).

So, I guess my point is that the way these systems are has evolved over time, and there are human reasons for different regions having different philosophies. While you could say the systems are not optimized for operation, or you can say that the objectives in building these systems has changed.