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VarioString -70


Solar charge controller with remote display

PV Input 200 (min) to 600 Voc


Maximum Power Point Tracking Charge Controller

Max PV Source Voltage(open circuit):600VDC

Max Input/Output Current:70 AMPS DC

Max Battery Charge Voltage:68 VDC

Nominal Battery Voltages:48V

Range of Operation PV Voltage:250~500 VoC

Operating ambient Temperature range:-20~55℃

Dimensions H/W/L(mm):120/220/350



VarioString series MPPT

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.

The VarioString solar charge controller maximizes the energy generated from solar panels in any solar installation. It contains an MPPT (Maximum Power Point Tracking) algorithm that continuously tracks the maximum power of the PV generator and automatically charges the batteries in an optimal way with all the available solar power.

VarioString-70 is an IP54 solar charge controller,PV Input 200 (min) to 600 Voc Maximize the energy generated from solar panels by adding a VarioString solar charge controller with maximum power point tracker (MPPT) to any solar installation.

How to Install the Solar Charge Controller


An exceptional device

∙ Reduces Balance of System costs (eliminates expensive wiring for parallel strings)

∙ Safe, simple and trouble-free connection with SUNCLIX™ (Phoenix Contact “tool free”) PV connector

∙ Safety guaranteed, thanks to the reinforced isolation between the PV generator and battery,allowing for independent earthing of the battery and/or solar modules

∙ World champion for efficiency in isolated converter with >98 %

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

∙ 4 step charger fully programmable for longer battery life

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

∙ Display with 9 LEDs showing status and current

∙ Suitable for any solar and battery system

∙ Use with Bolanmu battery charger/inverter to synchronize battery management for optimal efficiency


Combine with a range of accessories

∙ Display, programming and data logging remote control (RCC-03)

∙ Communication sets (Wifi model)

∙ Communication module (Xcom-232i/XcomCAN)

∙ Battery temperature sensor (BTS-01)

∙ Battery Status Processor (BSP)

∙ Communication with lithium battery BMS (Xcom-CAN)

∙ 2 additional auxiliary contacts (ARM-02)


VarioString-70 VarioString-120
Electrical characteristics PV array side MPPT MPPT 1/2 1+2 in parallel 1+2 in series
Maximum solar power
4200 W 3500W 7000W 7000 W
Maximum current 13 A 13 A 26 A 13 A
Maximum solar open circuit voltage 600V 600V 600V 900V
Minimum solar functional circuit voltage 100V 100V 100V 200V
Recommended MPPT voltage 250-500V 250-500V 250-500V 500-750V
Electrical characteristics battery side
Maximum output current 70 A 60 A 120 A
Nominal battery voltages 48 V
Operating voltage range 38 – 68V
Battery grounding possibility Battery + or battery –
Performances of the device
Maximum efficiency >98%
MPPT efficiency >98%
Maximum stand-by self-consumption < 20 mA(1W) <25 mA(1.25 W)
Charging stages 4 stages: Bulk,Absorption,Floating,Equalization
Number of steps, thresholds, end current and times
adjustable with the RCC-02/-03
Battery temperature compensation
(with accessory BTS-01/BSP)
–3 mV /°C / cell (25°C ref) default value
adjustable -8 to 0 mV /°C
Electronic protections
PV reverse polarity
Over temperature
Reverse current at night
Galvanic isolation
PV grounding possibility PV +, PV -, floating
Ground fault Protection Programmable
Operating ambient temperature range –20 to 55°C
Humidity 100% maximum 95 %, non-condensing
Ingress protection of enclosures IP54 IP20
Mounting location indoor
General data
Weight 5.51 kg 7.5 kg
Dimensions h/w/l[mm] 120 / 220 / 350 133 / 322 / 466
Solar generation connection(6mm²) SUNCLIX™ (Phoenix Contact Tool Free)
Parallel operation
(separated PV arrays)
Up to 15 devices
Max wire size 35 mm² 70 mm²
Glands M 20 × 1,5 2 x PG21
Network cabling Bolanmu communication BUS (included)
Configuration RCC-02/-03, Internal DIP switches for basic settings
Data logging With RCC-02/03, Xcom-232i on SD card · One point every minute
Accordance to standards
Conformity Low Voltage Directive (LVD) 2014/35/EU: EN/IEC 62109-1
Electromagnetic Compliance (EMC) Directive 2014/30/EU:
EN/IEC 61000-6-2, 61000-6-4



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