We are putting a solar array on the roof of an apartment complex. Each subarray will consist of 15 panels connected with microinverters to a circuit in that apartment's subpanel. The arrays will be adjacent to one another on the roof. Total of about 60KW of solar panels. Apartments all are fed out of one meter bank.
Obviously we have to bond the panel rails. But to where? Should the array rails be discontinuous between each subarray, so that the bonding wire from a subarray feeds back to only the one panel? Or should all the rails be connected together, since they are all right next to one another? I am worried that if we bond all the rails together on the roof, and also have bonding wires going back to the apartment subpanel ground bus, that we are creating a giant ground loop on the roof. Each microinverter communicates over powerline carrier to an internet gateway. Will such a ground loop cause communication problems? This certainly would be the case in audio equipment where ground loops are a big deal. Is a ground loop more likely to function as an antenna, picking up lightning voltages? Most all the grounding systems I've done (a lot) have always been some kind of star arrangement where everything bonds back to a single point. There may be a ground grid, or a loop under the building, or what have you, but all the equipment ground wires star back to the same point.
How would you approach panel and rail bonding?
Obviously we have to bond the panel rails. But to where? Should the array rails be discontinuous between each subarray, so that the bonding wire from a subarray feeds back to only the one panel? Or should all the rails be connected together, since they are all right next to one another? I am worried that if we bond all the rails together on the roof, and also have bonding wires going back to the apartment subpanel ground bus, that we are creating a giant ground loop on the roof. Each microinverter communicates over powerline carrier to an internet gateway. Will such a ground loop cause communication problems? This certainly would be the case in audio equipment where ground loops are a big deal. Is a ground loop more likely to function as an antenna, picking up lightning voltages? Most all the grounding systems I've done (a lot) have always been some kind of star arrangement where everything bonds back to a single point. There may be a ground grid, or a loop under the building, or what have you, but all the equipment ground wires star back to the same point.
How would you approach panel and rail bonding?