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Variostring, the most versatile charge controller in the market



Our R&D team has gone a step further in order to increase the versatility of this powerful MPPT charge controller. After the last software update (Xtender System Update R662), the VarioString adds a wider input voltage range to its outstanding features.

The Variostring charge controllers can now work with a larger input voltage range from 100 to 600V by MPPT channel, becoming 200-900V for the VS-120 when the two MPPT inputs are configured in series.

We are aware that offgrid systems requirements are often very challenging, this enhancement will improve the Variostring performance in the following situations:

  • Working with lower PV voltage extends the possibilities for system designs, as well as leverages drastically the impact of shading and hot spots even in small PV fields
  • In installations where smaller string designs are needed, the VarioString MPPT inputs will be operational just with 4-5 panels in series. The advantages of isolated high PV voltage MPPT charge controllers are now available for smaller systems.
  • A new step for higher efficiency to better compensate the partial shading in difficult PV topologies or project context, for example in the case snow during winter.
  • The Variostring allows to integrate other sources than solar. The larger range of voltage provides great versatility to integrate low-power wind and hydro turbines in your offgrid system.

NOTE: the new extended voltage range is available with a software update (Xtender System Update R662) for all VS-70 and for VS-120 with a hardware version larger or equal to 2.0 (produced after September 2014). The hardware version can be seen on the RCC in the system info screen. An update is safe for all versions, the incompatible models (before 09.2014) will simply keep the old 200V lower limit.