Cable Sizing and Length

Enphase_wire_diagOCPD = Over Current Protection Device, typically a 20A duplex circuit breaker, one is required for every 16(max) panel/inverters, 16 panels/inverters being the maximum allowed on one circuit.
PCC = Point of Common Coupling, usually where the generated power enters the hydro system. Note that FortisBC™ requires an external circuit breaker in section 3, (not shown on this diag) adjacent to the meter, so they can turn the panels off if necessary. BC Hydro no longer requires this.

From the Enphase Technical literature. NB  Distances are in feet.

This is the length and size of cable to go from the array to the service panel. Section 2 in the diagram above.

It is important to realize that each inverter in a string has to generate a slightly higher voltage than the one downstream from it to cause the flow of current from the array to the load center.

Case 1. An End Fed string fully populated with 16 inverters in Portrait. 240V nominal supply.

Note the line voltage at inverter 16, at 1.92v rise this is nearly the 2V max allowed.

Enphase_Vrise_16_inverters_in string

Case 2. A Center Fed string, with 2 sub branches.

Ideally the same number of inverters (max 8) in each leg, but un-ballanced (eg;4 on one roof 8 on another) is still better than 16 in an end fed string.  This is the  way recomended by Enphase to wire your strings.

Enphase_Vrise_inverters_center fed