
Modbus TCP
Marstek Venus E Gen 2.0 (battery)
Marstek
Overview
The Marstek Venus E Gen 2.0 is an AC-coupled residential battery storage system designed to maximize solar self-consumption and reduce grid dependency. The ModbusCloud template reads battery state of charge, instantaneous power flow, and cumulative energy throughput via Modbus TCP, while also exposing write registers for RS485 control mode, user work mode, force charge/discharge mode, and forcible charge power. This gives installers and asset managers direct visibility and programmatic control over the Venus E, Venus E Gen 2.0, and Venus C from the ModbusCloud portal.
Use cases
- Monitor battery state of charge continuously to confirm the Venus E is cycling as expected across the day.
- Track cumulative energy throughput to calculate effective cycle count and identify early capacity degradation.
- Alert on sustained negative power values to verify the battery is charging during planned solar surplus windows.
- Compare real-time power readings against smart meter data to verify zero-feed-in control is operating correctly.





