shaggy-solar/.claude/skills/calibration-charge/SKILL.md

---
name: calibration-charge
description: >-
  Guided runbook to re-anchor the 6 EG4 LifePower4 pack SoC counters by driving a
  full charge to absorption and verifying every pack resets to 100%. Use when pack
  SoC readings have drifted (e.g. one pack reads much higher/lower than the others
  while all pack voltages agree), when the user asks to "calibrate / balance / fix
  SoC / do a full charge", or on a monthly cadence. This is the ONE skill that
  changes inverter settings — and only the grid-charge ceiling, only on explicit
  user confirmation, and it reverts them. Everything else is read/monitor/verify.
---

# calibration-charge

Re-anchors drifted EG4 SoC counters. The BMS only resets SoC to 100% on a real
full-charge termination (high cell voltage + low taper current); the everyday
profile caps grid charging at 54 V, so the bank can go weeks without a full charge
and the counters drift. This runbook guarantees one full charge, then verifies.

## Action-policy exception (read this)
Unlike the troubleshoot-* skills, this one MAY change two inverter settings — but
ONLY `stop_charge_voltage` (54.0 → 0/Full) via the prepared calibration profile,
applied to BOTH units, and ONLY after the user explicitly confirms in-session. You
present the exact `flash.py` commands; the user runs them (or confirms you may). You
own pre-flight, monitoring, verification, and the REVERT. Never change anything else.

## 0. Load context
```bash
ROOT="$(git rev-parse --show-toplevel)"; SNAP="$ROOT/.claude/skills/lib/solar-snapshot"; HIST="$ROOT/.claude/skills/lib/ha-history"
FLASH="$ROOT/LVX6048/lvx-flash"   # flash.py + profiles/ live here
```
Read `$ROOT/.claude/skills/REFERENCE.md`. The two profiles: `eg4-lp4-v2.yaml`
(canonical/everyday) and `eg4-lp4-v2-calibration.yaml` (temporary; identical except
`stop_charge_voltage: 0`).

## 1. Pre-flight (must pass before charging)
```bash
"$SNAP" -w 16 -g 'lifepower4_[1-6]_(soc|pack_voltage|cell_voltage_max|cell_voltage_delta_mv|temperature_pcb|protection)' 'homeassistant/sensor/+/state'
```
Record and check:
- **Capture the "before" SoC spread** — this is what we're fixing. Confirm it's *drift*
  not real imbalance: if all 6 `pack_voltage` agree (±0.1 V) but SoC readings differ,
  it's counter drift (the target). If voltages actually diverge, STOP — that's real
  imbalance → troubleshoot-battery first.
- **Temps in charge range**: every `temperature_*` between ~5 °C and 45 °C. **Never
  charge LFP below 0 °C** (BMS should block, but verify). Abort if any pack > 45 °C.
- **No protection bits set**; cells reasonably balanced (`cell_voltage_delta_mv` < ~50).
- **Forecast/grid**: solar-only needs a sunny low-load day; grid-assist works anytime.

## 2. Choose the method (ask the user)
- **Solar-only — RECOMMENDED (no setting change, free, known-good):** on a sunny,
  low-load day with a full day ahead, solar drives the bank through the full CC/CV
  curve to bulk 56.4 V and holds absorption on its own — exactly the clean termination
  the BMS needs to re-anchor. No flash, no risk. Just monitor §4 and verify §5; skip §3.
  This is the method to default to.
- **Grid-assist — ADVANCED / UNVALIDATED:** the field flash.py calls
  `stop_charge_voltage` is really `battery_re_discharge_voltage`; the firmware **NAKs
  `0`/"Full"** (confirmed 2026-06-24 — both units rejected `BUCD480,000`). The corrected
  lever raises it 54.0 → 56.0 so grid charges higher, but it may band-oscillate near
  56 V instead of holding a clean absorption, so it is **not proven** to re-anchor.
  Only use as a supervised experiment when solar can't reach full and you accept it
  may not fully work. Needs §3.

## 3. Grid-assist (ADVANCED): apply the calibration profile (USER-CONFIRMED setter change)
Run `flash.py diff` FIRST and confirm the ONLY change is `stop_charge_voltage 54.0 ->
56.0` before applying. If any apply NAKs, the cluster is unchanged (flash.py aborts on
first failure) — fall back to solar-only.
Mirror to BOTH inverters (parallel cluster — mismatched settings throw fault 86).
`flash.py apply` stops powermon for exclusive USB, so MQTT telemetry pauses briefly.
```bash
cd "$FLASH"
sudo systemctl stop powermon.service powermon2.service
./flash.py apply --device /dev/lvx6048-1 --profile profiles/eg4-lp4-v2-calibration.yaml --confirm
./flash.py apply --device /dev/lvx6048-2 --profile profiles/eg4-lp4-v2-calibration.yaml --confirm
./flash.py compare --device-a /dev/lvx6048-1 --device-b /dev/lvx6048-2   # must match
sudo systemctl start powermon.service powermon2.service
```
Confirm via MQTT the new ceiling took (both units): `battery_recharge`/`stop_charge`
readback reflects Full, others unchanged.

## 4. Drive + monitor the charge (this is the agent's job — poll periodically)
```bash
"$SNAP" -w 16 -g 'lifepower4_[1-6]_(soc|pack_voltage|pack_current|cell_voltage_max|temperature_pcb)' 'homeassistant/sensor/+/state'
"$SNAP" -w 10 -g 'lvx6048_[12]_(device_mode|mppt1_input_power|ac_output_active_power)/' 'homeassistant/sensor/+/state'
```
Watch for, and re-poll every ~15–30 min as it climbs:
- `pack_voltage` rising toward ~56 V; `device_mode` should show charging/absorption.
- **SAFETY — abort and revert (§6) if:** any `cell_voltage_max` > **3.60 V** (BMS
  protects ~3.65; don't ride it), any pack temp > 45 °C, or any protection bit sets.
- **Absorption/taper:** once pack voltage holds near bulk and `pack_current` tapers to
  ~5 A/pack (≈0.05 C, < ~30 A total), the BMS will flip SoC to 100%. This hold is the
  part that actually re-anchors — let it finish, don't cut it early.

## 5. Verify the re-anchor (the whole point)
```bash
"$SNAP" -w 16 -g 'lifepower4_[1-6]_(soc|pack_voltage|cell_voltage_delta_mv)' 'homeassistant/sensor/+/state'
```
PASS = **all 6 packs read SoC 100%** (≥99) with pack voltages converged (spread
< ~0.1 V) and cell deltas still tight. The previously-drifted pack (e.g. pack 6) now
matching the others = counter re-anchored. Report before→after SoC spread.
If a pack still lags, it didn't terminate — extend the hold or investigate that pack.

## 6. REVERT (mandatory if you did §3 — do NOT leave the ceiling lifted)
```bash
cd "$FLASH"
sudo systemctl stop powermon.service powermon2.service
./flash.py apply --device /dev/lvx6048-1 --profile profiles/eg4-lp4-v2.yaml --confirm
./flash.py apply --device /dev/lvx6048-2 --profile profiles/eg4-lp4-v2.yaml --confirm
./flash.py compare --device-a /dev/lvx6048-1 --device-b /dev/lvx6048-2
./flash.py sync-check --device-a /dev/lvx6048-1 --device-b /dev/lvx6048-2
sudo systemctl start powermon.service powermon2.service
```
Confirm `stop_charge` is back to 54.0 on both units via MQTT.

## 7. Record
Note the date (for the ~monthly cadence) and before→after SoC spread. If drift returns
fast, consider the opt-in `soc_estimator` daemon backstop (see memory
`project_eg4_soc_drift_remediation`) as a longer-term fix.