# Byd Battery > Read BYD Battery-Box HVS/HVM/LVS/LVL home-storage telemetry through local Modbus or paired-inverter delegation, with read-only safety boundaries. - Skill: `hybridaione/byd-battery` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add hybridaione/byd-battery` - Raw SKILL.md: https://api.skillmd.com/api/skills/hybridaione/byd-battery/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: HybridAIOne (https://skillmd.com/u/hybridaione) - Updated: 2026-09-21 - Page: https://skillmd.com/skills/hybridaione/byd-battery --- # BYD Battery Use this skill for operator-approved monitoring of BYD Battery-Box Premium HVS, HVM, LVS, LVL, and older HV/LV family home-storage units. Prefer the bundled helper for all protocol details: ```bash node skills/byd-battery/byd-battery.cjs --format json read state-of-charge node skills/byd-battery/byd-battery.cjs --format json read pack-telemetry node skills/byd-battery/byd-battery.cjs --format json read cell-extremes node skills/byd-battery/byd-battery.cjs --format json read inventory node skills/byd-battery/byd-battery.cjs --format json read module-telemetry node skills/byd-battery/byd-battery.cjs --format json read alarms node skills/byd-battery/byd-battery.cjs --format json read firmware node skills/byd-battery/byd-battery.cjs --format json read be-connect-metadata node skills/byd-battery/byd-battery.cjs --format json read energy-counters node skills/byd-battery/byd-battery.cjs --format json read state-of-charge --via fronius ``` ## Safety Boundary **Read-only v1. Do not attempt mutating actions through this skill.** Remote shutdown, BMU reset, capacity reconfiguration, installer-app operations, cell-balancing overrides, write coils, and write-register requests are out of scope because they can affect a high-voltage DC battery. If a future v2 adds any mutating action, it must be red-stakes, require mandatory F8/F14 approval, and include installer handover instructions. Never ask for, print, or store installer-app passwords such as common default installer codes in helper output. Treat them as SecretRef-managed even if they are well known. ## Setup Set local BMU connection values in this order: 1. Browser admin: open the active HybridClaw admin URL ending in `/admin/secrets` and set the `BYD_BMU_*` values. 2. Browser `/chat` or TUI fallback: `/secret set BYD_BMU_HOST "192.168.1.50"` plus the matching port, unit id, and model values. 3. Local console fallback: ```bash hybridclaw secret set BYD_BMU_HOST "192.168.1.50" hybridclaw secret set BYD_BMU_MODBUS_PORT "8080" hybridclaw secret set BYD_BMU_UNIT_ID "1" hybridclaw secret set BYD_BMU_MODEL "Premium HVS" ``` The helper uses the SecretRef names in metadata and output. It does not expose the configured LAN host, port, unit id, model, or any installer secret in normal results. F3 host policy should allow only the BMU LAN host and Modbus port. BYD local Modbus does not require internet endpoints by default. ## Operation Rules - Use `read state-of-charge` for current SoC, SoH, power direction, and summary incident hints. - Use `read pack-telemetry` for pack/output voltage, current, power, and pack temperature. - Use `read cell-extremes` for max/min cell voltage, voltage spread, and max/min temperature. - Use `read inventory` and `read firmware` for service handoff: serial, model family, tower/module topology, BMU/BMS firmware, hardware revision when present in the BMU block, inverter family, and grid mode. - Use `read module-telemetry` for per-module voltage and temperature summaries decoded from the read-only diagnostic `0x0558` pages. Larger systems may require multiple sampled pages; the helper reads only the allowlisted diagnostic holding-register range and never starts measurement with a write. - Use `read be-connect-metadata` for the read-only commissioning and firmware metadata that can be recovered from local BMU registers. It intentionally does not log in to Be Connect Plus or handle installer passwords. - Use `read alarms` to decode the alarm bitmap into human-readable codes and R29 incident-card payloads. - Use `read energy-counters` to emit shape-stable R5 charge/discharge kWh rollup fields. - If local Modbus is not configured but the battery is paired to Fronius, use `--via fronius`. The helper delegates to R21.111 Fronius `local-power-flow` / `local-storage-realtime` surfaces instead of inventing a BYD cloud path. This checkout does not currently bundle a Fronius helper path; treat the emitted delegation payload as a handoff to the R21.111 skill once that skill is present. - Stop after the first Modbus connect, timeout, exception, or comms-lost failure. The helper emits an R29 `bmu-comms-lost` incident-card payload; do not retry-loop against the BMU. - Be Connect Plus has no public API contract. For v1, use `read be-connect-metadata`, `read firmware`, and `read inventory` for read-only commissioning metadata available from local BMU registers; do not automate installer-app login or password flows. ## Register Boundary The helper exposes only allowlisted read-holding-register ranges derived from the community BYD Battery-Box Premium Modbus maps: - `0x0000:0x0066` BMU identity, firmware, topology, inverter/grid mode. - `0x0500:0x0019` live SoC, SoH, pack voltage/current, alarms, energy counters. - `0x0010:0x0003` BMS parameter snapshot. - `0x0558:0x0041` tower/module diagnostic block. No arbitrary register passthrough exists. No write function codes are exposed. ## References - [BYD Battery-Box downloads](https://www.bydbatterybox.com/downloads) - [ioBroker.bydhvs community Modbus decode](https://github.com/christianh17/ioBroker.bydhvs) - [SmartHomeNG `byd_bat` plugin](https://github.com/smarthomeNG/plugins/tree/master/byd_bat) - [Home Assistant BYD HVS integration](https://github.com/Romelium/home-assistant-byd-hvs)