electricalforum.nz

Hi guys,

Hopefully someone can point me in the right direction here, I've tried the obvious places to find info, but all I can find is info on either grid tied or dedicated systems.

1) Can you install a solar system with an inverter that is solar fed with battery charging capacity and with grid top up (not grid tied) as a separate system for dedicated sockets/lights. So separate distribution board/wiring and sockets etc and leaving the exist mains fed system intact. The reason is grid tied is not permitted and the solution is to provide backup. All sockets would be for critical power and red in colour.

2) If you can, how do you handle earthing? Separate for the the new inverter fed board and a MEN link on that board?

Thanks for your help,

Ed

I can see no reason such an arrangement could not be made to comply. Basically it would be a "standalone" installation that just happened to be in the same structure as another installation.

Latest edition of "3010" allows for a separate installation using dedicated wiring from separate source; albeit in limited form and using a plug-in genset instead of battery+ inverter. In that scenario; the circuits are completely separate.
On the other hand, I don't believe ESRs / 3000 actually allow for it (yet). ESRs require compliance with "3000"; and for domestic that's part 2;.
In turn that requires a main earthing system including an electrode.

As does "4509" for standalone installations (although there seems no good reason for that particular requirement).

For your scenario I'd tie the earthing systems together, or even use common electride; to eliminate any chance of items connected to the two earthing systems being at different potential.

Thanks for your help Aleck