I guess I should also have said that each inverter is connected...

I guess I should also have said that each inverter is connected to a set of 20 panels so all the inverters work individually on the input side. They are connected in pairs on the output (grid) side to each of the 3 phases. All the inverters are grid tied so if there is a blackout the whole system shuts down and all the potential power that could be generated by the panels during the blackout is wasted.

Interestingly my nominal 3kW system only produces at best about 2.4 kW under near perfect conditions (and I have been told by a number of people that is all I should expect due to inefficiencies in the system) where I have observed each of his 5kW inverters produce a full 5kW for several hours each day so his nominal 30kW system actually does produce 30 kW for quite reasonable periods of time. Maybe his panels are actually larger than 250W and the inverter is limiting the maximum output to its rated capacity.