Battery storage (BESS) integration
Hoymiles HoyUltra 2 under smart control
The HoyUltra 2 is a liquid-cooled all-in-one battery cabinet of 261 kWh with a 125 kW power conversion system. Voltmasters EMS connects over Modbus TCP and steers charging and discharging quarter hour by quarter hour, aligned with market prices, solar production and site consumption.
Supported devices
- HoyUltra 2 (HESS-261-2h)
The HoyUltra 2 (HESS-261-2h): 261 kWh of battery capacity with a 125 kW power conversion system. Several cabinets in parallel are recognised as master and member automatically.
What the EMS gets out of your Hoymiles installation
- Trade on the imbalance market and dynamic prices, quarter hour by quarter hour
- Peak shaving: keep peak power and capacity tariff under control
- Maximise self-consumption together with PV and EV chargers
- Fluvius telecontrol and grid compliance, certification included
- Real-time monitoring with automatic incident detection
Why installers combine Hoymiles and Voltmasters
Place several cabinets in parallel and the EMS recognises by itself which cabinet is the master and which ones follow as members. Nothing has to be configured by hand: the EMS controls the master and reads out every rack separately. The Voltmaster Controller runs the optimisation locally in the cabinet, even without internet.
The technical bit, in short
- Connection over Modbus TCP, port 502
- The battery management system comes along automatically as a logical device
- Several cabinets in parallel: every cabinet needs its own reachable IP address
- Faults reported by the cabinet are translated into incidents, with their own severity per alarm level
How it works
How your Hoymiles connects to the EMS
Voltmaster Controller in the cabinet
The industrial DIN-rail controller sits next to the installation and runs the optimisation locally, even without internet.
Connect over the local network
You connect the device following the step-by-step guide in our documentation. We assist with commissioning on your first project.
Configure and go live
The installation appears in the platform: dashboards, control and monitoring are active right away.
FAQ
Questions about the Hoymiles integration
Which Hoymiles system does Voltmasters support?
The HoyUltra 2 (HESS-261-2h), the liquid-cooled 261 kWh battery cabinet with a 125 kW power conversion system. Hoymiles PV inverters are supported separately through the generic SunSpec integration.
Can I place several HoyUltra 2 cabinets in parallel?
Yes. On connecting, the EMS recognises by itself which cabinet is the master and which ones are members. The master receives the control commands, every member is simply read out.
Does the system keep working when the internet drops?
Yes. The Voltmaster Controller runs the optimisation locally in the cabinet. If the connection drops, control, peak shaving and the safety limits simply stay active.
How do I connect a Hoymiles HoyUltra 2 to the EMS?
The Voltmaster Controller connects to the device over the local network. The step-by-step instructions are in our documentation, and as a certified partner we guide your first commissioning from start to finish.
Sources
Manufacturer documentation
This page links to the manufacturer's own documentation for this device. Always check the most recent version at the manufacturer.
Ready to make your first project pay off?
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