Size of overhead wire

[SAP]

Back feeding 50 amp solar breaker residential, installing new 125 amp busing with 100 amp main service disconnect, overhead service. I'm using #4 AWG for my overhead conductors I size my conductors off of my 100 amp MSD, or should I be using #2

 

[jaggedben]

Per table 310.15(B)(7) you can use 4awg if it's a residential single phase service. The language is changing in the new code next month but I think the answer in this case is still the same.

EDIT: that's as long as you're not in a jurisdiction that requires the service conductors to match the bussing instead of the breaker. But that's usually a utility thing, and not required by PG&E.

 

[GoldDigger]

EDIT: that's as long as you're not in a jurisdiction that requires the service conductors to match the bussing instead of the breaker. But that's usually a utility thing, and not required by PG&E.

The only POCO I have heard of the requires service size to match "nominal" size of main (service disconnect) panel rather than main breaker size is Los Angeles DWP.
It makes it really hard to meet 120% rule by upsizing the panel only and using a small main breaker to match the service.

Sent from my XT1585 using Tapatalk

 

[jaggedben]

The only POCO I have heard of the requires service size to match "nominal" size of main (service disconnect) panel rather than main breaker size is Los Angeles DWP.
It makes it really hard to meet 120% rule by upsizing the panel only and using a small main breaker to match the service.

Palo Alto, too.