Personally, I would not like to have 400V
inside a house over here.
For one thing, there is no need for voltages like this, in the largest appliance(the Range), this would only be spread over two Phases + Neutral, this is still only 230V, but this is only in rural areas where the voltage regulation is poor.
With the advent of a lot of dairying out in the rural areas, we find ourselves using 3 Phases+ Neutral, because of the submersible pump, normally using 3 Phase, this is the only 3 Phase load, but the rest of the installation is balanced over the 3 Phases.
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