
Modbus TCP
M-TEC Energy Butler GEN3 (battery)
M-TEC
Overview
The M-TEC Energy Butler GEN3 is a modular hybrid battery storage system with an integrated inverter, designed for residential and small commercial PV installations. This template communicates over Modbus TCP using RTU framing over the device's built-in network interface. It reads battery power (charge and discharge direction via sign) and state of charge, and exposes a writable battery mode register that lets your portal control operating behaviour. Connecting the Energy Butler GEN3 to ModbusCloud gives installers and asset managers live battery telemetry and remote mode control from a single dashboard.
Use cases
- Monitor battery state of charge continuously to detect capacity loss across charging seasons.
- Track the power register sign to verify whether the battery is charging from PV surplus or discharging to loads.
- Alert on state of charge dropping below a defined threshold during extended periods of low solar yield.
- Write the batterymode register from the portal to switch between self-consumption and forced-charge modes during cheap-tariff windows.







