Solar6

I wired an AC·THOR 9s into Home Assistant to dump PV surplus into the hot-water tank — then the device refused every Modbus write. Here's the read-local, write-cloud fix.

Read every Huawei SUN2000 register straight into Home Assistant with the built-in modbus platform — no custom component that breaks on upgrade. A complete register-to-YAML map with the right data_type, scale, device_class and state_class for the Energy Dashboard.

Reading the AC·THOR 9s over Modbus TCP works, but writing is blocked at the device. Here's how I switched control to the undocumented my-PV Cloud API as a Home Assistant shell_command, with tested parameters and the gotchas nobody mentions.

A Home Assistant automation that compares your two MPPT strings and warns you the moment one drifts — early warning for shading, a dead module or a loose MC4 connector, with a night-time false-alarm guard.

My Huawei SDongle accepts exactly one Modbus connection — but Home Assistant, the AC·THOR and evcc all want the inverter's data. Here's the ~300-line asyncio cache server I wrote to feed all of them from a single quiet poll.

My inverter cloud shows self-consumption and autarky as pretty graphs. Home Assistant gives you raw counters. Here's how I rebuilt those numbers as template sensors I own.