Combiner Box SolaX TCBox-70 for 3 HS51 Towers
The SolaX TCBox-70 is the accessory that allows you to connect up to three battery towers in parallel of the TSYS-HS51 high-voltage storage system, with an operating current of up to 70 A. It is used when the required capacity exceeds that of a single 8-module tower: not to be confused with the Series Box TBHS51, which instead connects two strings in series.
The SolaX TCBox-70 is the connection accessory that allows you to connect up to three battery towers in parallel in the TSYS-HS51 high-voltage storage system, with an operating current of up to 70 A. It is the component added when the required capacity exceeds what can be managed by a single chain of modules.
When it is needed: the three expansion levels of the TSYS-HS51
The TSYS-HS51 system expands in stages, and each step requires a different component, something often forgotten in quotations:
- One tower, from 2 to 8 modules (10,2-40,8 kWh): only the TBMS-S51-8 BMS is required, which also acts as the base
- Two towers in series, up to 13 modules (66,5 kWh): the Series Box TBHS51 is also required
- Up to three towers in parallel: the TCBox-70 is required
These are three separate accessories with different functions, not alternatives to one another. Confusing them is the most frequent error when sizing a commercial storage system: the Series Box connects two chains in series within the same system, while the TCBox-70 places complete towers side by side in parallel.
SolaX TCBox-70 technical specifications
| Function | Parallel connection of multiple TSYS-HS51 battery towers |
| Connectable towers | up to 3 |
| Operating current | up to 70 A |
| Compatible system | TSYS-HS51 (TB-HS51 modules with TBMS-S51-8 BMS) |
| Typical use | Commercial and industrial storage systems beyond the capacity of a single tower |
Why connect multiple towers in parallel
Connecting multiple towers in parallel is not only useful for increasing the available kWh. Distributing the same energy across multiple chains reduces the current passing through each one, and therefore the thermal and electrical stress on the individual modules, with a positive effect on the system’s service life. It also allows a more flexible physical layout: three low towers take up less height than a single tall tower and can be distributed in a technical room with space or floor load constraints, considering that each module weighs 46 kg.
Frequently asked questions
What exactly is the TCBox-70 used for?
It allows up to three battery towers of the TSYS-HS51 system to be connected in parallel, with current up to 70 A. It is the accessory used when the required capacity exceeds what can be obtained from a single chain of modules or when it is preferable to distribute the storage system across multiple physical units.
What is the difference between TCBox-70 and Series Box TBHS51?
They have different functions. The Series Box TBHS51 connects a second chain of modules in series within the same system, when exceeding the 8 modules managed by the BMS, up to 13 modules and 66,5 kWh. The TCBox-70, on the other hand, connects complete towers in parallel, up to three. In a large-scale system, both may be present.
Is it also needed if I have only one tower?
No. With a single tower from 2 to 8 modules, the TBMS-S51-8 BMS is sufficient, as it manages the modules and acts as the base. The TCBox-70 should only be included when multiple towers are placed side by side in parallel.
Which batteries is it compatible with?
With the TSYS-HS51 system, consisting of 5,1 kWh TB-HS51 modules and the TBMS-S51-8 BMS. It is not compatible with previous-generation SolaX Triple Power batteries, which have a different connection architecture.
Which technical data should be checked before ordering?
The number of towers actually planned, the maximum current required by the hybrid inverter, and the compatibility of the BMS firmware version. For multi-tower configurations, it is advisable to request confirmation of the connection diagram, because the layout of the power cables and communication buses must be followed exactly to avoid imbalances between the towers.
