Multiple single phase string inverters. SMA claims this is the preferred method
in Europe.
Might be more expensive, but does have some advantages.

Dick Ratico
Solarwind Electric


--- You wrote:
Hello fellow wrenches,
   I am hoping someone here has come across this before and might have a
suggestion or two for us. I have a client who has a large piece of land
and the financing for a 500 kw solar "farm" in Maine. The predicament I
am in is that the closest three phase primary is more than a mile away.
The existing single phase, 7200 volt lines to the three phase portion
of the grid could easily handle the -80 amps extra load coming onto it
from the central inverters, it is just that I cannot find, anywhere, a
practical way to make this work, that is, converting the three phase
output of the central inverter(s)(480v) to the requirement for the grid
(7200 v single phase). Any ideas?? Suggestions?

Thank you,
Daryl DeJoy
NABCEP Certified PV installer
Penobscot Solar Design
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