# EG4 LifePower4 v2 → HA Monitoring Install

Target: Debian-family Linux (developed on Raspberry Pi CM5), one USB-to-RS-485
adapter per pack's **RS485** socket, HA MQTT broker on the LAN.

> **Shortcut:** [`install.sh`](./install.sh) automates §3–§7 and supports
> `--dry-run` for a no-hardware smoke test. This doc explains what it does
> and how to do it by hand.

Path conventions: `$BASE` = root of this package (e.g. `~/solar/eg4battery`).

## 1. Prerequisites

- `uv` on `$PATH` ([docs](https://docs.astral.sh/uv/))
- `sudo`
- **One USB-to-RS-485 adapter per pack**. FTDI-based is what we've tested
  (FT232R + MAX485 combo, identified by the Linux kernel as `FT232R USB UART`
  with a unique serial-number suffix). CH340 / CP210x also fine — adjust
  the udev rule's vendor/product ID.

## 2. Cabling — read this before wiring

LP4V2 back panel has four RJ45 sockets: `CAN`, `RS485`, `Comm1`, `Comm2`.
Only `RS485` is relevant for our daemon:

| Socket | Use for monitoring?                                                 |
|--------|---------------------------------------------------------------------|
| CAN    | No — separate bus, CAN signaling, for inverter BMS comms             |
| RS485  | **Yes.** External monitor port. Pin 1-2 = B/A. Modbus RTU at 9600.   |
| Comm1  | No — inter-pack hub bus (19200 Modbus). Leave for pack daisy-chain.  |
| Comm2  | No — same internal bus as Comm1.                                     |

The stock EG4 USB-RS-485 cable (included with each pack) is already wired
correctly for the RS485 socket (pins 1-2 / A-B).

**Topology**: each pack gets its own adapter plugged into its **RS485** socket.
No daisy chain required for monitoring — each pack is a dedicated bus. The
Comm1↔Comm2 daisy chain between packs is separate and carries the inter-pack
hub bus (not our concern).

## 3. udev rule

Grants `dialout` group access to FTDI USB-serial adapters.

```bash
sudo install -m 644 "$BASE/etc/udev/rules.d/99-eg4-rs485.rules" \
                    /etc/udev/rules.d/99-eg4-rs485.rules
sudo udevadm control --reload-rules
sudo udevadm trigger --subsystem-match=tty
ls -l /dev/serial/by-id/        # expect one symlink per adapter
```

## 4. Daemon binary

```bash
sudo install -m 755 "$BASE/bin/eg4-battery" /usr/local/bin/eg4-battery
```

uv handles deps; no venv work on your side.

## 5. Config

Canonical template: [`config/eg4-battery.yaml.example`](./config/eg4-battery.yaml.example).

```bash
mkdir -p ~/.config/eg4-battery
install -m 600 "$BASE/config/eg4-battery.yaml.example" \
               ~/.config/eg4-battery/eg4-battery.yaml
# Edit — see "mode selection" below
```

### 5a. mode selection

- **`modbus_per_pack`** (default / recommended). Each pack listed with its own
  `port:`, `address:` and `baud:` — the daemon opens one serial port per pack
  and polls each independently.
  ```yaml
  bus:
    mode: modbus_per_pack
    timeout_s: 1.0
    poll_interval_s: 10.0
  packs:
    - name: lifepower4_1
      address: 0x40
      port: /dev/serial/by-id/usb-FTDI_FT232R_USB_UART_<ID1>-if00-port0
      baud: 9600
    - name: lifepower4_2
      address: 0x40
      port: /dev/serial/by-id/usb-FTDI_FT232R_USB_UART_<ID2>-if00-port0
      baud: 9600
  ```

- **`active`** (legacy, V1 hardware only) — single shared bus, EG4 7E/0D
  protocol at 9600. Not used on V2 Auto-Addressing hardware.

- **`passive`** (diagnostic) — listen-only Modbus sniff at 19200. See
  [`NOTES.md`](./NOTES.md) "Modes" for details.

### 5b. MQTT creds

Replace `<MQTT_BROKER_IP>`, `<MQTT_USER>`, `<MQTT_PASSWORD>`. `install.sh`
will not auto-start the service while those placeholders remain.

## 6. Smoke test without hardware

```bash
eg4-battery -C ~/.config/eg4-battery/eg4-battery.yaml --dry-run
```

Mock transport, one cycle per pack, prints every discovery-config and
state-topic / payload to stdout. Confirms the pipeline end-to-end before
hardware is involved.

## 7. systemd

```bash
sudo install -m 644 "$BASE/etc/systemd/system/eg4-battery.service" \
                    /etc/systemd/system/
sudo systemctl daemon-reload
sudo systemctl enable --now eg4-battery.service
journalctl -u eg4-battery.service -f
```

Service includes `Environment=PATH=…` so uv is found under systemd.

## 8. Bring up additional packs

When a new pack comes online:

1. Plug its adapter into the pack's **RS485** socket and power the pack.
2. `ls -l /dev/serial/by-id/` — note the new symlink.
3. Add / update an entry in `~/.config/eg4-battery/eg4-battery.yaml`:
   ```yaml
   - name: lifepower4_N
     address: 0x40
     port: /dev/serial/by-id/usb-FTDI_FT232R_USB_UART_<ID>-if00-port0
     baud: 9600
   ```
4. `sudo systemctl restart eg4-battery.service`. The journal shows
   `pack lifepower4_N: recovered after N failed cycle(s)` within ~10 s when
   the pack starts responding, and HA auto-discovers ~65 entities.

## 9. Verify MQTT flow

```bash
# modbus_per_pack: all named + raw register entities per pack
mosquitto_sub -h <broker> -u mqtt -P <pass> \
    -t 'homeassistant/sensor/lifepower4_+_pack_voltage/state' \
    -t 'homeassistant/sensor/lifepower4_+_soc/state' \
    -t 'homeassistant/sensor/lifepower4_+_cell_voltage_delta_mv/state' \
    -v
```

## 10. Swapping modes later

Change `bus.mode` in the config, restart the service. Config reshape varies
per mode — see §5a. No binary redeploy needed.