The contactors or relays inside Multiplus (and probably Quattro and others) show a circuit diagram for switching off the neutral conductor to AC mains. I wonder about the reason for doing this as is not used in all the remaining AC installations. Exeptions are for appliance behind „Schuko“ type connectors where hot conductor and neutral can be exxchanged depending from the plug direction. If the neutral switching to public AC grid is for regulation purpos only, what could be the reason for this rule ? For my experience, the neutral switching is a big danger for asymmetric loads in 3 phase grids. Anyway transfer switches have high efforts to reconnect the disconnected neutral to earth again using late break / early make contactors.
At least with the use of own grid transformer who produces non public neutral, I cannot see any reason on why not to connect all neutrals permanently. If there is any remaining neutral current, it will not be registered in any kilowatthours registration devices. If this is possible (or recommended) there would be the possibility to improve the resistance of the used contactor with parallel use of the 3 or 4 available NO switches.
