SolaX TBMS-S51-8 BMS for HS51 Battery Tower
The SolaX TBMS-S51-8 is the BMS and base of the TSYS-HS51 energy storage system: it manages from 2 to 8 TB-HS51 modules of 5,1 kWh (10,2-40,8 kWh per tower), with 60 A nominal and 70 A peak in charging and discharging, CAN and RS485 communication, 90% DoD and IP66 rating. Essential: without the BMS, the battery modules do not work.
The SolaX TBMS-S51-8 is the battery management system (BMS) of the TSYS-HS51 storage system. It forms the base of the tower, manages from 2 to 8 TB-HS51 modules of 5,1 kWh each and communicates with the hybrid inverter. Without it, the battery modules do not operate.
The component without which the tower does not exist
In modular high-voltage storage systems, the BMS is not an optional accessory: it is the component that balances the cells, manages charging and discharging, monitors temperature and activates module heating, communicates the state of charge to the inverter and opens the circuit in the event of a fault. The TBMS-S51-8 is also the physical base of the tower: the modules are stacked on top of it. One must therefore be provided for each installed tower, not one per system: if the project includes two towers, two BMS units are required, plus the Series Box TBHS51 to connect them in series.
SolaX TBMS-S51-8 technical specifications
| Function | BMS and base of the TSYS-HS51 system |
| Managed modules | from 2 to 8 TB-HS51 modules (10,2 - 40,8 kWh per tower) |
| Maximum system capacity | up to 66,5 kWh with 13 modules and Series Box |
| Charge and discharge current | 60 A nominal, 70 A maximum |
| Managed depth of discharge | 90% |
| Communication | CAN and RS485 |
| Protection rating | IP66 |
| Off-grid operation | Supported (depends on the paired hybrid inverter) |
| Dimensions / weight | 600 x 225 x 376 mm / 18,5 kg |
| Certifications | IEC 62619, IEC 62040, EN 62477, VDE 2510 |
Remote diagnostics and maintenance
The BMS exposes the system status through CAN and RS485, the two buses used by SolaX hybrid inverters to read state of charge, cell voltages, temperatures and alarms. This enables remote fault diagnostics and software updates without on-site intervention: for a storage system installed in a technical room or in a distant commercial installation, being able to identify the module that is unbalancing the tower without dismantling anything significantly reduces service times.
How to size the tower
The number of modules must be chosen based on two parameters, not just one. Energy, meaning the kWh needed to cover evening and night-time consumption, and power, which increases with the number of modules because the bank voltage rises: it ranges from approximately 6,1 kW nominal with two modules to 21,5 kW with seven. A user with high draw peaks may therefore require more modules than would be needed for autonomy alone. The limit of a single BMS remains eight modules.
Frequently asked questions
Is a TBMS-S51-8 required for each battery tower?
Yes. The BMS is also the base on which the modules are stacked and manages up to 8 modules. A system with two towers therefore requires two units, plus the Series Box TBHS51 for the connection between the two. With the TCBox-70 it is possible to parallel up to three towers.
How many battery modules can I connect to a TBMS-S51-8?
From a minimum of 2 to a maximum of 8 TB-HS51 modules of 5,1 kWh, corresponding to a capacity from 10,2 to 40,8 kWh per tower. A configuration with a single module is not provided: the system requires at least two modules to operate.
What is the maximum charge and discharge current?
The system operates at 60 A nominal with peaks up to 70 A. The corresponding power depends on the bank voltage, which increases with the number of modules: the same current on a seven-module tower produces more than three times the power compared to a two-module tower.
Which inverters is it compatible with?
With SolaX hybrid inverters designed for HS series high-voltage batteries. Compatibility must be checked on the specific model and firmware version, because the minimum number of modules required at start-up may vary: on X3-ULTRA, for example, the system requires at least three modules.
Is the BMS included when I purchase the battery modules?
No, it is a separate component. TB-HS51 modules are purchased individually and the TBMS-S51-8 BMS must be added once per tower. Any connection accessories between towers, such as the Series Box TBHS51 and the TCBox-70, must also be considered when calculating the quotation.
