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:

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:

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
• ioBroker.bydhvs community Modbus decode
• SmartHomeNG byd_bat plugin
• Home Assistant BYD HVS integration