Whole home wiring for backup - Route grid input into Sol-Ark/Lux or line-side and into panel breaker?

[godawgs]

A question for the solar wizards: All of the manuals for Sol-Ark, Luxpower, and EG4 say that for a whole-home backup system, you have to route the wiring from the utility disconnect to the inverter GRID input(s), then wire from the inverter LOAD/BACKUP output to the service panel lugs. This makes sense.

My curiosity is: Is it possible to simply tap the line side of the panel (after the utility disconnect but before the service panel), feed that to the inverter GRID input, then wire the inverter LOAD/BACKUP to a suitably sized breaker in the service panel? Following the NEC 20% rule, a 200A service panel can have a 40A breaker, not quite the 50A capable of the suitable 12K inverters, but the inverter output could be limited to 9600W in this setup.

As I said, just a curiosity as I'm not seeing any issues with this setup, other than you lose some inverter output capacity. And running a house on 40A could be challenging, on occasion.

 

[TechRider]

I'd say that's a no go. If you had a separate panel just for those load, yes. Otherwise you'll be bridging the two connections together. Sol-Ark supports a sub panel that is powered off the load side then can back-feed on the grid side using the CT's as a way to measure how much needs to be output.