adminandClaude Opus 5
0a1e61dbc9
Turns the reference RS485 controller into something a technician can install at a client site: a typed config form instead of YAML, an ingress UI that names misconfiguration in words, and persistent state that cannot be broken by a timezone. Why an add-on rather than YAML packages or blueprints: - Blueprints cannot create helpers, and the maintenance cycle is a state machine whose phase and completion date must survive restarts. - YAML packages need filesystem access, a configuration.yaml edit and a restart - none of which belong in a client install. - Add-ons authenticate with SUPERVISOR_TOKEN, so there is no long-lived token to generate, store or leak on someone else's machine. - Requires HA OS/Supervised. Container and Core installs cannot run add-ons at all, which is a market decision, not an oversight. The control law and the maintenance machine are pure functions with no Home Assistant imports, and both ship with runnable checks (22 and 22 assertions). Every assertion corresponds to a rule whose absence caused an observed failure on hardware - the saturation duration term, the clamp-before-slew ordering, the deadband, the sign convention. One behaviour deliberately differs from the implementation it replaces: when its inputs go missing this commands 0 W rather than replaying the last setpoint. The reference version kept replaying, which the hardware watchdog cannot catch - from the ESP32's side, Home Assistant is still talking to it. Includes the ESPHome firmware (now parameterised: node name, inverter rating, watchdog timeout) and the optional RS485 e-stop. FIELD-GUIDE.md carries the commissioning gates, all judged on the wire rather than on how Home Assistant looks, plus the written statement a site without an e-stop needs signed. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_016NckgXecasQb2eSsPYNSW6
3.0 KiB
GoodWe RS485 Controller — Home Assistant add-on repository
Replaces a GoodWe battery inverter's vendor controller with a local one: holds net grid exchange at zero by emulating the inverter's smart meter over RS485, and runs the monthly battery maintenance cycle the vendor box was doing.
repository.yaml add-on repository metadata
goodwe_controller/ the add-on
config.yaml manifest + options schema (the per-site config form)
app/ the controller
control.py the control law — pure functions, no I/O
maintenance.py the monthly cycle state machine
hass.py Supervisor/Core API access
store.py persistent state in /data
mqtt.py optional status entities
web.py ingress UI
main.py orchestration, heartbeat, failsafe behaviour
test_control.py runnable checks — no framework needed
test_maintenance.py runnable checks — walks a full cycle in fake time
DOCS.md the add-on's documentation tab
firmware/goodwe-master.yaml ESPHome config for the T-CAN485
estop/rs485_log.py optional RS485 e-stop / bus witness
FIELD-GUIDE.md installation, commissioning gates, troubleshooting
Install
Settings → Add-ons → Add-on store → ⋮ → Repositories → add this repository's URL, then install GoodWe RS485 Controller.
Requires Home Assistant OS or Supervised. Add-ons cannot be installed on HA Container or Core.
Read this first
The inverter holds its last command forever. It has no meter-timeout of its own — a controller that dies mid-command leaves the battery running until a human intervenes. Measured on real hardware: 5 kW of discharge held for 113 seconds after a controller went silent.
Three layers exist because of that, and only the third covers the Home Assistant machine itself dying:
- ESP32 watchdog — no fresh setpoint for ~30 s → command 0 W, and keep commanding it.
- Wind-down before firmware updates — 0 W written before the update starts.
- RS485 e-stop (optional) — writes 0 W after 30 s of total bus silence.
Sites sold without the e-stop must have the acknowledgement in FIELD-GUIDE.md
§10 signed.
Development
The control law and the maintenance machine are pure Python with no Home Assistant imports, so they run anywhere:
cd goodwe_controller
python3 test_control.py
python3 test_maintenance.py
Both must pass before shipping any change. They are not unit-test theatre —
each assertion corresponds to a rule whose absence produced an observed failure
on real hardware, and the comments in control.py say which.
Compatibility
- GoodWe ES / BP family inverters (AA55 / RS485 meter-bus generation)
- The protocol is reverse-engineered. There is no vendor contract, and a firmware change on GoodWe's side could break every installation at once. Say so when you sell it.