I'm installing an 8.1 kW solar system and running two inverters. My hope is to run both inverters to a sub-panel and move a few basic home breakers into the sub-panel. Since the Utility company wants me to install an AC Disconnect, I would like to install it between my sub-panel and the main. This will allow them to disconnect my solar power from the grid and hopefully leave me with basic lighting in the house if they do.

First question - any issues with this approach?
Second - If that works what size AC-Disconnect do I need? My sub-panel is 100 amps, pluggerd into 100amp breaker in the main.

Appreciate any help thank you!

I purchased the following, but since it's only 60 amps should I return and go with something like a 95amp?

Quare-D DU222RB Safety Switch Square-D DU222RB Safety Switch 250V/Outdoor, 60A, 2 Pole No Fuse

Thanks for the information

Hmm. If you are going to move a few circuits to the sub panel, then they won't be connected to the utility company any more... correct? If I am reading what you are saying correctly, your solar system will be independent of the utility company. If that is correct, you do not need any disconnect, since they aren't connected.

Am I missing something?

The Sub-panel is connected to the main. But the utility company would like the ability to disconnect my solar from the grid when they are doing repairs. At night when solar is not producing power I would be pulling from the Grid.

OK... that makes sense. There is a device called a transfer switch, which is designed when installing a generator. Their operation interlocks the two sources so that either the generator or the utility company is supplying power... but never both at once. Would this fit your application?

Good question, this is where my lack oh knowledge comes in. My hope was to just place 100 amp AC Disconnect switch between the Main and the Sub. Something that the utility company could just walk up to and switch to off and lock it. I've seen a Square D DU323RB that appears might work.

What size breaker feeds your sub-panel? The breaker serves as disconnect.

It's 100 amp breaker. The manual states that the utility company requires an AC Disconnect between a grid-tie inverter and the AC load center, close to the AC service entrance, with a visible and lockable handle.

You're on the right track with the disconnect. Just purchase one (non - fused) that's rated equal or higher to the circuit breaker.

Great thanks!

I have sort of what you are asking about hanging on my wall outside.

Here's a picture, if you want specifics let me know.

panel.jpg photo - John Kloepper photos at pbase.com