marstek-rs

Rust library to talk to Marstek energy storage devices on the local network, without the Marstek cloud.

Crate	Content
marstek-proto	Sans-IO protocol core: encodes requests, decodes replies. No I/O, no async runtime.
marstek	tokio transport on top of marstek-proto. Re-exports it as marstek::proto.

Protocols

Open API (marstek::open_api): JSON-RPC over UDP, default port 30000. Enable the Open API in the Marstek app first. Supported methods: Marstek.GetDevice, Bat.GetStatus, ES.GetStatus, ES.GetMode, ES.SetMode, EM.GetStatus, BLE.GetStatus, Ble.Adv, and discovery by broadcast.

Devices drop many requests. The client sends a request again every 1 s until the reply arrives, and keeps 1 s between two requests to the same device. Faster requests stop the device from refreshing its CT values.

Modbus TCP (marstek::modbus): reads holding registers, port 502. The register map in marstek_proto::modbus::venus_e3 covers the Venus E 3.0.

The units of the Open API values follow the official documentation (Rev 3.1).

Demos

cargo run -p marstek-discover                          # find devices
cargo run -p marstek-status -- 192.168.1.107           # Open API status
cargo run -p marstek-set-mode -- 192.168.1.107 auto    # switch mode
cargo run -p marstek-modbus-read -- 192.168.1.107 [1]  # Modbus values

Sources

• Open API: the official client aiomarstek and ha-marstek-local-api.
• Modbus registers: marstek_venus_modbus.

License

MIT or Apache-2.0, at your option.