Files
shaggy-solar/eg4battery/README.md
noise 8dafce7dfe Docs: reflect this session's findings across the repo
- top-level README.md (new): system overview, subsystem map, skills pointer,
  notable findings.
- eg4battery README/NOTES: 3 -> 6 packs (pack 6 oddball 0x01/115200); SoC drift
  + calibration section; closed-loop comms evaluated and rejected (loses per-pack
  telemetry, no native protocol, doesn't fix drift); how to force a grid charge
  via output-priority SUB.
- LVX6048 README: closed-loop pending item -> resolved decision; new "SoC
  calibration & known firmware quirks" section (POP single-digit/POP01, MCHGC
  charge-lock, re_discharge=re-discharge can't exceed float, PIRI lag, powermon
  adhoc wedge); skills pointer.
- lvx-control README: POP encoding fix, POP crc-but-applies quirk, verify-by-
  behavior, grid-charge-via-SUB usage.
- troubleshoot-inverter skill: corrected the stale "dead string per inverter"
  claim — both strings healthy; low PV is tilt/heat/shade/curtailment.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-25 21:46:02 -04:00

5.1 KiB
Raw Blame History

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 6 packs publishing in modbus_per_pack mode, each on its own FTDI RS-485 adapter (packs 15 at addr 0x40/9600; pack 6 is an oddball at addr 0x01/115200). 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 §"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 for architecture, register map, LVX6048 compatibility findings, and bring-up checklist.

SoC drift & calibration

The per-pack BMS SoC is coulomb-counted and drifts because the conservative LVX6048 charge profile rarely drives a true full charge, so the counters never re-anchor to 100% (observed 870% spread across packs at an identical resting voltage — they're all physically at the same charge; the spread is pure drift). Fix is a periodic full charge to absorption, which re-anchors every pack to 100%. Automated by the calibration-charge skill (solar-only, or grid-assisted via output-priority SUB on a cloudy day) — see ../.claude/skills/calibration-charge/ and ../.claude/skills/lib/grid-cal-monitor.

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

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
  • ../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. 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.