For each this, would the down below statements be a safe design consideration for the household residence with 3 Ph Provide & load of 6kW with 40A key Isolator & ELCB. On top of that, earthing consists of connecting the neutral stage of the power supply system on the earth https://twikkers.nl/blogs/180987/Keeping-Power-Cool-Modern-HVAC-Approaches-for-Substation-Design