Hi,
As you know, all electricity from your national grid is ultimately three phase in origin. If the neutral gets disconnected somewhere in the supply, then the Line-Neutral voltage becomes the Line-Line voltage, and any connected devices may well get overvoltaged and blow up.
For a 10kW installation, supplied with three phase, how can we ensure that the Line-Neutral voltage does not rise up to the line-line voltage if there is a loss of neutral connection?