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Problems with CT setup/configuration

We've been having ongoing issues with our installer on getting our CTs setup correctly for our Powerwall/solar install (they're a solar installer just getting into batteries and don't quite know what they're doing).

Setup is:
  • Powerwall 2 with Backup Gateway 2
  • Solar Panels with Envoy
  • Solar/Grid/Backup Load/Supply all connect in a generation panel (which I now realize we could have replaced with an internal panelboard in the gateway :()
  • 3 breakers aren't backed up (dryer/oven/EV)
Current CTs are:
  • CT 3 (Solar 1 x2)
  • Neurio with 4 Site CTs connect to L1/L2 of non-backup loads and L1/L2 of supply to generation subpanel
My question is about that last one. That doesn't seem to match what I've seen in the manual, and it's showing some weird data in the Tesla app (e.g., underreporting grid usage or overreporting solar). Should there be 4 CTs for Site? From what I've seen in various manuals/videos, there should be 2 CTs on the grid L1/L2 instead (although it's not clear I have the room for that).

Below are a diagram of our setup and photos of the main panel (with the Neurio and its 4 CTs), generation panel (with the solar CT), and gateway.

Diagram.png Main Panel.jpg Generation Panel.jpg Gateway.jpg

The only thing I know about the question of 3 or 4 CTs is some hobby experience with using a Neurio. Generally one CT per phase is what is done. That would mean 4 CTs. I did have luck using CTs on each phase of my loads and only one CT on the solar generation. The solar is a balanced output so you can measure one phase and multiply the result by two to get the total. I had to tweek the settings on the Neurio to get its display of kWs to correspond to my Inverter reported output.

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