Wiring help needed!!

[Donna Sidelinger]

We are installing a 15.2 KW EP Cube solar system which consists of 30 Canadian Solar 400W panels, (2) EP Cube Inverters with 3 batteries each, and a Smart Gateway. We want to wire directly into our Main Breaker Panel and power the whole house. We have been given a wiring schematic (which I am attaching) but we are not sure about the main power connection from the meter??? Do we leave the main power coming into the main panel and then wire the inverters into the (2) 40Amp breakers in our panel? How do we get grid power connected to our smart gateway. I appreciate anyone able to give us some help and maybe provide photos of the appropriate wiring procedures. Thanks - Donna

 

[Hedges]

The schematic shows meter feeding un-fused switch, followed by smart gateway, after that 200A breaker panel with main breaker.

What does your house presently have for service entrance?
You could post a photo.

You might want to modify the posted plans so they don't show address or phone.
The web is full of stalkers like me

One guy posted a receipt, and before he could delete it I showed satellite photo of his house. (kind of like sub captains sending ship captain a photo of his vessel in the crosshairs.)

 

[Donna Sidelinger]

Hi Hedges, We have a 200 Amp main breaker panel in the house. So forgive my slowness but is this what you are saying?

Grid Meter to the Disconnect then from the disconnect to the smart gateway then out of the smart gateway to the main breaker of the main service panel?

This would mean that we would no longer be feeding the main panel directly from the grid meter???

Also we will be wiring the two inverters into (2) 40 Amp breakers in the main panel does all this sound right?

Attaching a very crude line drawing of what I think you are saying???

Thanks.
Donna

 

[Hedges]

Is your 200A main breaker panel inside the house, separate from the utility meter? Or is utility meter in same box as breaker panel?
If separate, is there any other disconnect, or is the 200A breaker on main panel the first disconnect mechanism?

If separate meter, that is good. If no separate disconnect, you need to have utility (or electrician) unplug meter to shut off power while a 200A disconnect switch is installed. Then meter can be plugged back in, and the switch can be used to shut off power whenever work is being done on the new system. If you have an electrician install the switch, you could do everything else yourself. You could do the switch yourself, but need to complete it and get power restored before freezer thaws.

Yes, the line drawing resembles the schematic you showed previously.
I don't see anything going between Cube inverters and Smart gateway except neutral and ground. But I think neutral and ground should route together with L1 and L2, not by another path.

There needs to be some datacomm between Cube and Smart Gateway so after Gateway has disconnected from grid, it can tell Cube to switch from UL-1741 grid tie inverter to grid-forming inverter.

If your system does have grid disconnect relay remote from PV and battery, that's something another forum member was interested in.

 

[Hedges]

Oh, two 40A breakers backfeeding main panel with 200A main breaker appears to violate 120% rule (sum of main breaker and backfed breakers can't exceed 120% of busbar rating.) If a 225A busbar then two 35A breakers would comply, or if main breaker replaced with smaller one.

Also, backfed breakers should be at far end of breaker panel, not middle like one of them is shown. So their current subtracts not adds.

 

[greensoldierusa]

I wish you luck I am installing the same thing and need to figure the wiring out (panel side etc). Every electrician around here says no to anything related to solar, unless they are part of a solar install team that is. I have a 400 amp service so im scratching my head allot lately.