Is it Possible to add a Schneider XW Pro to a Sub-Panel

[10bad10]

Hey solar community, I need to know how to set up a Schneider System before committing any money to building a battery room in a certain location. I currently have an area where I plan to build a cinder block battery room. It is about 150’ from my main panel and has 3/0 between it. In this battery room I want to put a Schneider system with EG4 batteries that is fed by some DC coupled solar. With this system I hope to accomplish the following:

• I want to sell any excess solar I produce from the DC system back to Edison (I have grid tied solar already with Net-Metering in CA with SCE)
• I want to have whole home backup when the grid goes down. Logistically that means feeding power back to the main panel through the sub-panel.

I am just wondering is this possible with only one run of 3/0 between the main and sub panel? Also, I know this would all be easier if the Schneider was put line side by the main panel but that is just not feasible and not where I want to house the batteries. I’ve attached a diagram to help. Any assistance would be greatly appreciated.

 

[BentleyJ]

Based on the drawing, the system would not provide all the features you desire.
The Sub-Subpanel located in the battery room would be powered by the inverter AC Output. The inverter AC Input would be powered via a new 2 pole breaker in the subpanel. When utility power goes out the inverter disconnects the AC Input side in compliance with UL1741, anti-islanding provisions. Translation: The inverter would use the batteries to power the Sub-Subpanel but everything upstream would be dead including the grid-tie inverters. If you moved the grid-tie breaker to the Sub-Subpanel then you would have an AC coupled system and the grid-tie inverters would stay active and help power the back-up panel only.

I believe if you were to install a Schneider BCS near the main panel you may be able to get the functionality you need. Not an expert on this relatively new product, only browsed the manual a couple of times.

 

[Tmoney2007]

If you want whole home backup, you're going to have to have an automatic transfer switch to disconnect your main panel from the meter so you don't back feed onto the grid when the grid is down.

The XW Pro has an internal relay that can handle up to 60A, but that would require your service to be 60A or less and for there to be wires from the meter, to the inverter and then back to the loads.

You can use a Schneider BCS or some other kind of service rated relay/contactor setup to disconnect the meter/grid during a blackout and feed power back into the rest of the house from the AC1 input, but it wouldn't be arranged exactly like you are thinking and I don't know that the existing conductors that go from the battery sub panel to the casita sub panel to the main would be appropriately sized (though they probably are). This is going to include informing the utility at minimum and almost certainly permits and inspections, and I have absolutely no idea how it would affect your metering agreement (I sense that avoiding this is part of your goal).

Check out page 30 (or 32 for a generic relay/contactor setup) of the multi unit design guide and you can see what the wiring diagram looks like for full home backup. AC1 is bidirectional like you want, AC2 is used as a grid sense terminal (that would require something like a 10awg wiring run back to the meter/ATS). I can't guarantee that it would work with a single inverter, but I think it would. A distributor could get in contact with Schneider for you to confirm. I also can't guarantee specifically how it would interact with your grid tied AC coupled microinverters.