Overview
The VarioString series is a high voltage MPPT solar charge controller designed to optimize battery charging and maximize solar production. It is notable for its high conversion efficiency from 900V solar power to 48V battery voltage, featuring galvanic isolation between the PV and battery. Manufactured in Switzerland, it comes with a 10-year warranty.

Electrical Characteristics
PV Array Side:
- Maximum solar power recommended: 4200 W to 7000 W depending on configuration.
- Maximum current: 13 A to 26 A.
- Maximum solar open circuit voltage: 600 V to 900 V.
- Recommended MPPT voltage: 250-750 V.
Battery Side:
- Maximum output current: 70 A to 120 A.
- Nominal battery voltage: 48 V.
- Operating voltage range: 38 - 68 V.

Performance
- Maximum efficiency: > 98%
- MPPT efficiency: > 99.8%
- Charging stages: Bulk, Absorption, Floating, Equalization.
- Adjustable parameters with RCC-02/-03.
- Battery temperature compensation available.

Protections
- PV reverse polarity, over temperature, reverse current at night.
- Galvanic isolation and programmable ground fault protection.

Environmental Specifications
- Operating temperature range: –20 to 55°C.
- Humidity: 95% non-condensing.
- Ingress protection: IP54/IP20.

General Data
- Weight: 5.51 kg to 7.5 kg.
- Dimensions: 120/220/350 mm to 133/322/466 mm.
- Parallel operation: Up to 15 devices.

Communication and Configuration
- Network cabling via STUDER communication BUS.
- Configuration through RCC-02/-03 and internal DIP switches.
- Data logging available.

Certifications and Warranty
- Conforms to LVD 2014/35/EU and EMC Directive 2014/30/EU.
- ISO certified factory 9001:2015/14001:2015.
- 10-year warranty.

Additional Features
- Reduces Balance of System costs.
- Safe and simple connection with SUNCLIX™ PV connector.
- Suitable for any solar and battery system.
- Compatible with Xtender system for synchronized battery management.
- Accessories available for enhanced functionality.