glenn schrooyenandClaude Opus 5
aae74d7571
Review fixes. A. test_loop.py takes 73 s, not the ~35 s claimed in three places. That number is the whole defence against a future developer deleting a slow test, so it was understated by 2x in exactly the place it matters. Corrected - and it is now ~95 s (measured 93 s), because this commit adds the scenario below rather than trimming windows to make an inconvenient number smaller. Both call sites carry an instruction to re-measure if the windows change. B. "242 checks" was test_p1's own count quoted as the total for all five suites. The real figure is 395 across the five, plus 14 here. And the finding this PR should have led with. stale_input_s and the `inputs missing -> 0 W` claim both live INSIDE cycle(), so pre-fix, on a meter whose value happened to repeat, that claim could not fire at all. Constant meter, SoC entity dying at t=4 s, one binary: pre-fix final target 220.0 W, reason 'loop -> 220 W' post-fix final target 0.0 W, reason 'safety -> 0 W' The old controller held 220 W through the whole input outage with its status line still reading loop -> 220 W, and layer 1 does not cover that on a `meter_source: off` install - no P1 age sensor is published, so the firmware has nothing to veto on, while the heartbeat keeps its watchdog fed. The pre-fix behaviour was not "holds a stale command safely"; it was a failsafe a repeating meter switched off. Asserted in test_loop.py, both halves. Three points of reasoning tightened, none of them wrong before: - the re-tune is unreachable by construction, not merely by the reset: the combined cycle rate is max(arrival rate, 1/floor), never the sum, and 1/15 s is strictly slower than the ~1/5 s arrival rate. That holds only while the floor exceeds the meter's update interval - and the schema minimum of 5 s is exactly the reference meter's interval. Flagged for validate.py, not fixed here. - the ~11 s lower bracket is not only a dropped poll: a 5.0 s poller against a 4.97 s meter beats, so about every 14 minutes the poller steps over an update entirely. Reaching 15 s takes a beat-skip AND a failed poll. - the "freshness is decided upstream" guarantee is transport-conditional. On `meter_source: off` the grid figure comes straight from hass.number() with no age gate. Running the full law is still right; the claim is narrower than it was stated. The 15 s default is not independently justified - it rests on the firmware's 30 s ingest veto and moves if that ever does. Said beside the constant. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Du77usMj8XNKNFZGmUiWDa
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
docs/GoodWe-RS485-Field-Guide.pdf the guide techs carry (10pp, A4)
docs/build_guide.py its single source - rebuilds the HTML and PDF
FIELD-GUIDE.md how to edit and rebuild the guide
Picking this up after a break? Read HANDOVER.md first — current state,
what is known broken, and what to do next.
Install
Settings → Add-ons → Add-on store → ⋮ → Repositories → add
https://gittea.kammenstraatha.duckdns.org/admin/goodwe-addon
then install GoodWe RS485 Controller.
⚠️ The repository must be PUBLIC for this to work. Home Assistant clones it
anonymously; against a private repo the store shows nothing and gives no useful
error. If it must stay private, install locally instead: copy
goodwe_controller/ into the machine's /addons/ folder, then
ha store reload — it appears as a Local add-on.
⚠️ Bump version: in goodwe_controller/config.yaml for every change.
Supervisor keys the built image by that version, so without a bump it silently
reuses the old image and your fix appears not to work — on your bench and on
every client's machine.
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
Check the serial number, not the model name. Characters 6-8 of the serial are the platform tag:
| tag | platform | verdict |
|---|---|---|
ESU EMU ESA BPS BPU EMJ IJL |
105 — ES/EM/BP, AA55-era meter bus | supported |
SPB SPN |
745 — SBP G2 (GW…-SBP-20) |
no |
ESN ESC |
745 — ES G2 (GW…-ES-20) |
no |
ETU EHU BTU … |
205/745/753 — ET/EH/BT hybrids | no |
SDT DST MSU NSU … |
PV-only inverters — no battery to control | no |
A "-20" or "G2" suffix means a different platform with a different meter
protocol. The tags come from the goodwe library's PLATFORM_105_MODELS, which
is also what Home Assistant's own integration uses to pick a protocol.
- 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.