Last spring we mounted ten of the old solar panels from our first Tesla solar install on our solar overhang. The wiring to connect the old inverter to the panels took a bit of study. I used the wiring diagram that came with the system to help recreate the connections. The only part that didn’t work was the old auto shutoff boxes. I could not get the power to pass through them so I just removed them. The panels were wired in strings of 5 with the two strings wired in parallel as in the original configuration. They were grounded with 6 gauge bare copper wire and grounding clips. All the wires were fed to a connection box and connected to wires in metal conduit to travel down to the equipment wall. The current Tesla combiner box does not allow new loads so it couldn’t be connected there.
So this box has its own path to the power panel. Another connecting box at the equipment wall fed a 20 amp dc circuit breaker. A new device was added at this point. It is a Revo Power DC switch that can be controlled by WiFi. It is rated for 400 volts and will send the power to the new EM3 minisplit or to the inverter. This allows us to steal the power to run the AC in the summer but feed it to the grid in the winter.
I consulted ChatGPT to find code compliant wiring for the system and it said no neutral was required for this setup. But when the inverter had a fault, I asked again and it said oh with that box you do need a neutral. I ended up wiring a separate neutral to the inverter and that cleared the fault. The box was large enough to take another 20 amp breaker on the grid feed side. Chat GPT gave full installation instructions.
I contacted Tesla to ask about seeing the system output in the app. They will send a communication device since I lost the old one. Once that is hooked to the inverter the data should show up in the app. The system was already approved by the power company so the installer I consulted saw no issues with adding it back. If it is not reflected in their records I will call them and ask for reconnect.
In the meantime the system is producing power and is delivered to our panel. This image is taken before the install was completed. The old inverter is being wired. Then the wire goes to the smaller shutoff and then to the panel.
