shaggy-solar/openevse/README.md

OpenEVSE → Home Assistant (MQTT discovery)

The OpenEVSE WiFi firmware natively publishes raw values to openevse/<key> on whichever MQTT broker you've configured it against, but it does not publish HA discovery configs. Without those, HA can't see any of it unless you hand-write mqtt: sensor: blocks in configuration.yaml.

This package fixes that with a single one-shot tool that publishes retained homeassistant/.../config payloads pointing at the OpenEVSE state topics the firmware already provides. No daemon, no broker proxy — HA subscribes to OpenEVSE's own topics directly once discovery is in place.

Status: live

23 entities exposed for the charger at 10.0.0.249 (device id a048):

sensor.openevse_power            W      live charging power
sensor.openevse_voltage          V
sensor.openevse_amp              A      (firmware reports mA; converted in HA)
sensor.openevse_pilot            A      pilot current the EVSE is signalling
sensor.openevse_max_current      A      hardware/soft-limit ceiling
sensor.openevse_session_energy   Wh
sensor.openevse_total_energy     Wh     total_increasing → Energy dashboard
sensor.openevse_total_day        kWh    total_increasing
sensor.openevse_total_week       kWh
sensor.openevse_total_month      kWh
sensor.openevse_total_year       kWh
sensor.openevse_session_elapsed  s
sensor.openevse_uptime           s      diagnostic
sensor.openevse_temp             °C     (firmware reports tenths-°C; converted)
sensor.openevse_temp_max         °C
sensor.openevse_status           text   "active" / "disabled" / "sleeping" / ...
sensor.openevse_state             #     numeric state code
sensor.openevse_srssi            dBm    diagnostic — Wi-Fi signal
sensor.openevse_freeram          B      diagnostic
sensor.openevse_total_switches   #      diagnostic — total_increasing
binary_sensor.openevse_vehicle           plug — car connected
binary_sensor.openevse_evse_connected    connectivity (diagnostic)
binary_sensor.openevse_manual_override

Availability is wired to OpenEVSE's retained announce topic (openevse/announce/<id>), which the firmware uses as its LWT — entities flip to "Unavailable" if the EVSE drops off the broker.

How it works

1. bin/openevse-publish-discovery connects to the broker, reads the retained openevse/announce/<id> payload to learn the device id and metadata (name, http URL).
2. Builds 23 homeassistant/{sensor,binary_sensor}/openevse_<key>/config payloads — one per entity. Each declares state_topic pointing at the matching openevse/<key> topic, plus device_class, unit_of_measurement, state_class, value_template (where unit conversion is needed), suggested_display_precision, and a shared availability block.
3. Publishes them with QoS 0, retain=true. HA picks them up immediately via its existing homeassistant/# subscription.

The two unit conversions baked into discovery payloads (so HA never sees raw units):

Source topic	Raw value	HA value
openevse/amp	milliamps	A (/ 1000)
openevse/temp[_max]	tenths-°C	°C (/ 10)

What's in the box

openevse/
├── README.md                          ← you are here
├── Install.md                         ← run order, verification, rollback
└── bin/
    └── openevse-publish-discovery     ← one-shot (PEP-723 uv inline-script)

Quick start

Broker creds default-load from ~/.config/powermon/powermon.yaml (mqttbroker.{name,port,username,password}), so on this host:

~/solar/openevse/bin/openevse-publish-discovery

That's it. To remove every entity later:

~/solar/openevse/bin/openevse-publish-discovery --purge

See Install.md for verification steps, dry-run preview, and CLI overrides if your broker isn't the one in powermon.yaml.

Related packages

• ../LVX6048/ — same broker, same discovery pattern (via patched powermon).
• ../eg4battery/ — same broker, same discovery pattern (via eg4-battery daemon).