We have only had 2 "grid surges" that have affected our turbine in the 9 months of operation. The turbine carried on in "working mode" but was only producing under 6 watts when according to the wind speed it should have been generating well over 1kWh.
On the first occasion we rang our installer who then rang Proven who told him it was probably caused by a grid surge and to go through the normal routine to manually shut the system down, wait 10 minutes then manually start it back up and this should sort it out. This we did and problem was solved.
This happened again last week so that is what we did and again problem solved.
It's not difficult to manually close it down and restart it - just have to follow a sequence of switching off the grid current and the inverter and following the same routine back again. (Don't have to put the brake on the actual turbine).
I'm sure there is a technical way of explaining the situation but we can't tell you what it is
