# 2026-04-26 — inverter MQTT entity cleanup

Mirrors the eg4battery cleanup landed earlier today. Same set of issues
(no precision hints, missing `state_class`, dead/misleading entities)
plus a couple of powermon-specific quirks.

## What changed

1. **New patch (g) — `outputformats/hass.py`.** Rewrites powermon's HA
   discovery-payload assembly so:
   - `suggested_display_precision` is set per unit (V/A → 1 dp,
     W/VA/% → 0, °C → 0, Hz → 1, Ah → 1, etc.). Frontend now renders
     `52.5 V` instead of `52 V`.
   - `state_class: measurement` is set by default for numeric sensors
     that don't have an explicit class. Required for HA's long-term
     statistics + Energy dashboard wiring; previously only
     `ac_output_active_power` had it.
   - `last_reset: <datetime>` removed from every payload. HA spec
     allows it only on `state_class: total` cumulative counters; on
     `measurement` sensors HA warns and ignores. Upstream emits it
     unconditionally.
   - `force_update: "true"` removed from default. Forced HA to record
     every state publish even when value unchanged; bloats DB for
     slow-changing fields (battery V, currents, temps).

2. **Patch (a) tweak.** `"DC-AC power direction"` → `"DC AC power
   direction"`. Causes the HA entity_id to become `dc_ac_power_direction`
   (underscore, conforming) rather than the previous `dc-ac_power_direction`
   (hyphen, non-conforming).

3. **`excl_filter` added to GS command** in both `powermon.yaml` and
   `powermon2.yaml`:
   ```yaml
   excl_filter: '^(battery_voltage_from_scc.*|mppt2_.*|setting_value_configuration_state)$'
   ```
   Drops 7 always-zero / always-misleading fields:
   - `battery_voltage_from_scc`, `battery_voltage_from_scc2` — no separate
     SCC bus on this hardware
   - `mppt2_input_voltage`, `mppt2_input_power`, `mppt2_charger_temperature`,
     `mppt2_charger_status` — nothing connected to PV input #2; would auto-
     resurrect if MPPT2 is ever wired
   - `setting_value_configuration_state` — internal config-write echo, no
     operational value
   - **kept**: `parallel_instance_number` (will become useful when parallel
     comms work) and `load_connection` (will become live when output is
     enabled)

4. **`tmp/lvx-purge-orphans` new tool.** Same shape as eg4-purge-orphans:
   publishes empty retained payloads to the deprecated discovery-config
   topics so HA forgets the orphans the broker still has cached.
   Idempotent. paho-mqtt 1.x and 2.x compatible.

## Net effect

| Metric                                      | Before | After | Delta |
|---------------------------------------------|--------|-------|-------|
| Published state topics per inverter         | 29     | 23    | −21 % |
| Total stack (2 inverters)                   | 58     | 46    | −12 (16 orphans purged) |
| Voltages displayed at integer precision     | many   | 0     | now show 1 dp |
| Sensors qualified for HA long-term stats    | 1      | all numeric | proper trends + Energy dashboard wiring |
| Bogus `last_reset` warnings on HA startup   | 58     | 0     | clean log |
| Recorder rows per slow-changing entity / 24h| ~17 k  | only on change | DB bloat reduced |

## Files touched

```
A  powermon-patches/hass.py            (new patch g)
M  powermon-patches/pi18.py            (patch a tweak: "DC-AC" → "DC AC" in field name)
M  powermon-patches/README.md          (document patch g)
M  install.sh                          (copy hass.py during install)
M  Install.md                          (§5(g) doc)
A  tmp/lvx-purge-orphans               (one-shot orphan cleanup)
M  config/powermon/powermon.yaml       (excl_filter added to GS; password placeholder restored)
M  config/powermon/powermon2.yaml      (same)
A  2026-04-26.md                       (this file)
```

## How to verify

```bash
# Discovery configs now include precision hint + state_class
mosquitto_sub -h <broker> -u mqtt -P <pass> \
    -t 'homeassistant/sensor/lvx6048_1_battery_voltage/config' -W 5 -v
# Expect: ..., "state_class": "measurement", "suggested_display_precision": 1, ...
# Expect: NO "last_reset" or "force_update" fields

# Renamed entity surfaces with underscore
mosquitto_sub -h <broker> -u mqtt -P <pass> \
    -t 'homeassistant/sensor/lvx6048_1_dc_ac_power_direction/state' -W 5 -v
# Expect: state value (e.g. "donothing")

# Verify dropped fields are gone
mosquitto_sub -h <broker> -u mqtt -P <pass> \
    -t 'homeassistant/sensor/+/state' -W 12 -v \
  | grep -E 'lvx6048_._(battery_voltage_from_scc|mppt2|setting_value_configuration|dc-ac)'
# Expect: zero matches
```

## Rollback

```bash
# Revert source
git checkout HEAD~1 -- LVX6048/

# Re-apply old patches to live install (the unpatched hass.py comes from pip)
cd LVX6048 && ./install.sh   # idempotent, will copy old hass.py back

sudo systemctl restart powermon.service powermon2.service
# Old entities (battery_voltage_from_scc, mppt2_*, etc.) republish on next cycle.
```