Correct way to monitor Solar usage with weird solar/grid setup?

[devsolar]

Our panel setup is a little odd. We have an outside meter panel with a single 125A breaker in it that is the house’s main breaker. All of the individual breakers for the house are in a sub-panel just on the other side of the wall inside the garage. It is in this panel that I attached the 200A CTs to monitor overall usage, and then attached 50A CTs for the individual circuits I wanted to monitor. We also have solar on the rooftop that is tied into the main meter panel “ahead” of the main 200A CTs in the inside sub-panel. I cannot move the main 200A CTs to the outside meter panel for a variety of reasons. I am currently monitoring the solar by running a single 50A CT to the solar breaker panel which is next to the meter main panel. I used some 2.5 mm extension cables and I set the multiplier to 2 for the circuit. The production reported by this is inline with what the revenue grade meter the solar leasing company put in to monitor usage, so I know I am getting good valid data.

The setup looks kinda like so:

[grid] -> [outside meter panel] -> [125A breaker] -> [inside sub-panel w/200A CTs around feed and individual circuits]
.                           |
.                 [solar subpanel] <- [solar inverter] <- [rooftop panels]

The problem I am seeing is that solar production is getting counted incorrectly under total usage and shows up in the balance as a huge number. I am exporting to the grid, but the Emporia app doesn’t show it:

My utility shows that I exported 2.7 kWh to the grid, but the app clearly doesn’t reflect that.

I recognize the fact that I have a non standard setup here, and there’s little I can do to fix that.

• This topic was modified 4 months, 3 weeks ago by devsolar.

[devsolar]

One note to add. If I subtract the solar production of 28.362 from the net usage of 25.707 I get -2.655. If you round that up, you get the 2.7 kWh that my utility says I exported.

Alternately, you can subtract the 28.362 from Total Usage of 47.251 to get 18.889. And then if you subtract the 21.544 Balance from that, you once again end up with -2.655. So the data to compute what I’m exporting is there, it just can’t be easily presented in the app.

[devsolar]

I ended up moving the 200A CTs to the meter panel before where the solar is connected, so it is now correctly monitoring.

Here’s the main meter panel. Solar is fed from the bottom. I connected the 200A CTs right below the breaker. Feeding the leads through the rear conduit was  amusing (difficult). But it now works properly.

And here’s what the monitoring looks like now:

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