no mixing of earths?

[jason121]

isnt that the answered to this thread

 

[PeteC]

thanks all for your comments!

SMA17000TL meets DIN VDE 0100-712 and does not require B type RCD fault protection, but if RCD required 100mA per inv. min, because of differential currents. As a barn 300mA max.

It could be the DNO need to address their supplies~ there is a good IEC thread in progress on PNB TNS supplies. But even if both supplies come from the same Tx then they should still need earth systems seperated? maybe that's a DNO call.

If both became TT then what means to earth? The bonded array to the structural framework certainly could have a low Ra. If low enough then I could seek permission from the building engineers to use?