# EG4 LifePower4 v2 → Home Assistant

Daemon that polls EG4 LifePower4 48V 100Ah v2 (Auto-Addressing) packs over
RS-485 and publishes per-pack telemetry to MQTT with HA auto-discovery.

## Status: live

All 3 packs publishing in `modbus_per_pack` mode, each on its own FTDI
RS-485 adapter. Per pack, ~70 named entities + 136 raw `register_NN` series:

```
lifepower4_1_pack_voltage            52.56 V     (16 cells × 3.285 V)
lifepower4_1_cell_01_voltage         3.285 V
lifepower4_1_cell_voltage_delta_mv   2           (outstanding balance)
lifepower4_1_soc                     100 %
lifepower4_1_capacity_ah             100.0 Ah
lifepower4_1_temperature_pcb         55 °C
lifepower4_1_model                   "LFP-51.2V100Ah-V1.0"
lifepower4_1_firmware_version        "Z03T21"
lifepower4_1_firmware_date           "20260206"
... plus 14 warning bits, 14 protection bits, all 136 raw registers
```

The decoder maps registers to fields per a layout reverse-engineered from
the EG4 BMS Tool's Mach-O binary (see [`NOTES.md`](./NOTES.md) §"Modbus
polling" and §"Register map"). Each cycle, the daemon issues two Modbus
fn=0x03 reads per pack — block 1 (39 regs at 0x0000) for live status, and
block 2 (91 regs at 0x002D) for counters + model + firmware strings —
mirroring what the vendor BMS Tool itself does.

## Modes

Set by `bus.mode` in `~/.config/eg4-battery/eg4-battery.yaml`:

| Mode              | When to use                                             |
|-------------------|---------------------------------------------------------|
| `modbus_per_pack` | **Default.** One FTDI per pack's RS485 port. Fully decoded HA entities. |
| `active`          | Legacy 7E/0D (V1 firmware only). Not used on V2 hardware. |
| `passive`         | Listen-only Modbus sniff (19200). Diagnostic use.       |

See [`NOTES.md`](./NOTES.md) for architecture, register map, LVX6048
compatibility findings, and bring-up checklist.

## What's in the box

```
eg4battery/
├── README.md                            ← start here
├── Install.md                           ← detailed walkthrough + mode-switch howto
├── NOTES.md                             ← architecture, register map, port matrix
├── install.sh                           ← idempotent installer (supports --dry-run)
│
├── bin/eg4-battery                      ← single-file daemon (uv PEP-723 inline deps)
│
├── config/eg4-battery.yaml.example      ← template, multiple-pack config
│
├── etc/                                 mirror of target paths (Pi side)
│   ├── udev/rules.d/99-eg4-rs485.rules
│   └── systemd/system/eg4-battery.service
│
├── homeassistant/                       ← drop into your HA config dir
│   ├── README.md                        (what goes where + retention tiers)
│   ├── recorder.yaml                    (exclude noisy / diagnostic entities)
│   ├── template_sensors.yaml            (derived: power, temp_max, cell_imbalance, stack rollups)
│   └── lovelace_overview.yaml           (3-pack stack dashboard)
│
└── tmp/                                 ad-hoc diagnostics
    ├── port-probe                       (single-cycle 9600/19200/7E probe)
    ├── eg4-snapshot                     (47-reg dump for BMS Tool cross-check)
    └── bms-tool-ref/                    (unpacked vendor BMS Tool for RE reference)
```

## Quick start on a fresh host

```bash
cd ~/solar/eg4battery
./install.sh --dry-run          # mock cycle, prints MQTT payloads, exits

# Edit ~/.config/eg4-battery/eg4-battery.yaml:
#   - For modbus_per_pack: one 'packs:' entry per pack, each with port + address + baud
#   - mqtt.host / username / password

./install.sh                    # real deploy; auto-starts once creds are filled
journalctl -u eg4-battery.service -f
```

## Related packages

- [`../LVX6048/`](../LVX6048/) — inverter-side monitoring via PI18 over USB-HID.
  Same MQTT broker. Between the two packages, HA sees every useful number from
  the stack.

## Acknowledgements

- `battery/eg4_lifepower.py` — V1 protocol decoder adapted from
  [`Louisvdw/dbus-serialbattery`](https://github.com/Louisvdw/dbus-serialbattery).
  Historical; V2 firmware moved to Modbus on a different port.
- EG4 Electronics `lv_host.app` — the vendor BMS Tool; its Qt binary's SQLite
  schema and strings gave us the register-to-field mapping.