The variostring high voltage MPPT solar charge controller ensures an optimal charge of the battery maximizing the solar production. First of its kind, the variostring achieves the highest conversion efficiency in the world from high voltage solar power (900V) to 48V battery voltage, including a galvanic isolation between the PV and battery. 100% designed and manufactured in Switzerland, the variostring offers a 10-year warranty.



Display with 9 LEDs showing status and current

Suitable for any solar and battery system

Low self-consumption: <1W in night time mode

Up to 15 variostring in parallel on the same communication bus (105kW)

up to 15 devices

Optimal usage in an xtender system with synchronized battery management

Advanced battery accessories

bts 01 Temperature sensor

bts 01

Temperature sensor

bsp Advanced battery processor (lead-acid)


Advanced battery processor (lead-acid)

xcom CAN Communication with lithium BMS

xcom CAN

Communication with lithium BMS

Display, datalogger, monitoring and communication

rcc 02/03 Configuration, display, datalogger

rcc 02/03

Configuration, display, datalogger

xcom LAN/GSM Remote monitoring (Portal & App)

xcom LAN/GSM

Remote monitoring (Portal & App)

xcom 232i/CAN/485i Communication bridges (openstuder)

xcom 232i/CAN/485i

Communication bridges (openstuder)

Compatible accessories

vario solar charge controller


solar charge controller

xtender battery inverter


battery inverter

arm 02 External auxiliary contacts module

arm 02

External auxiliary contacts module

Technical data


variostring vs120