actually a really good idea
does this mean PV production is effective curbed ? or battery stored ?
No, I'm just not backfeeding a 200A or 225A busbar in breaker panel.
The objective is for 100% of PV (15.4kW) to backfeed grid if not used locally.
Rather than, 200A busbar 200A main breaker 40A PV breaker 32A PV = 7680W,
or with 225A busbar and 70A PV breaker, PV = 13,440W
Also, can take in grid power and supply 200A main panel from battery inverter.
Polaris is probably good for 400A or more.
PG&E -->
meter -->
200A main breaker -->
Polaris -->
100A fused safety switch || 200A sub-panel || 100A sub-panel
The safety switch will go to PV aggregator panel (or battery inverter with PV inverters downstream)
Each sub-panel can be fed direct from grid (from Polaris), or can switch interlocked "generator" breaker and be fed from battery inverter.
Normal operation:
Grid feeds 200A panel with larger heating loads.
Grid feeds (or is fed by) 100A safety switch, which feeds battery inverter, backfed with PV. Battery inverter goes through load-shed relay to generator breaker of 100A important loads panel.
Critical loads are directly on PV aggregator panel, always on (so long as battery holds out.)
That's my soon-to-be system. Sunny Boy, Sunny Island for battery backup.
My sister's will be different:
200A panel (center fed, I hope 120% rule has been relaxed)
7.68kW Sunny Boy Smart Energy with 15kW of PV, optional HV battery.
That can only backfeed 7.68kW, but remaining power from PV up to 10kW can go to battery for later backfeed.
Eventual goal is to feed her ADU, and sell power to renters in primary dwelling.
In your case, a 400A panel with 320A breaker could allow huge amount of PV backfeed. 160A of PV breaker?