Fronius Symo is a three-phase inverter from Fronius with a maximum AC output of 17.5 kW and peak efficiency of 98% that is engineered, designed and manufactured in Austria and is suitable for systems of every size and solar array.

Fronius is a top-rated inverter brand in the solar industry. The Fronius Primo, the Fronius Symo, and the Fronius Symo Hybrid inverters are three of its most popular products, each with various advantages and disadvantages. 

This inverter review will explore Fronius Symo’s features, functionality, reliability, quality, and limitations.

Our analysis will help you decide if a Fronius Symo inverter is a worthwhile investment for your solar panel needs.

So what are you waiting for? Let’s dive right into this Fronius inverter review!

solar panel under blue sky

What is the Fronius Symo Solar Inverter?

The Fronius Symo inverter is a transformerless three-phase inverter (single-phase is also available). As a result, Fronius solar inverters boast power categories ranging from 3.0 to 20.0 kW, suitable for systems of every size and solar array. 

The design of the Fronius solar inverter is compact and lightweight. It has a maximum AC output of 17.5 kW, can be modified to suit the system’s needs and has a peak efficiency of 98%. 

aerial photography of grass field with blue solar panels

You might be wondering who built these incredible inverters. Let’s study one of the best solar inverter brands on the market.

In 1940, Gunter Fronius started a one-person enterprise in Pettenbach. Fronius Solar Energy was officially founded in 1992 as a small business enterprise. Their first milestone was the invention of the Fronius Sunshine inverter.

Over time, their business significantly expanded as they produced a wide range of solar products. Moreover, the company spent 75 years developing long-term charging batteries. Their research concluded with the invention of the Business Unit Perfect Charging, revolutionary battery storage that changed the solar industry.

  • Fronius Symo Device Concept

 The Fronius inverter comprises six components:

  1. Housing cover,
  2. Inverter,
  3. Wall bracket,
  4. Connection area incl. DC main switch,
  5. Data communication area, and
  6. Data communication covers.

The design and functionality of the inverter provide a maximum level of efficiency while guaranteeing safety during both installation and usage. Fronius also designs its inverters to operate with grid-tied PV systems. 

brown brick house with solar panels on roof
  • The Working Principle of Fronius Symo Inverters

Suppose you’re uncertain about how to choose a solar inverter for your solar system. In that case, you may consider the Fronius for its unique operational style.

The Fronius Symo inverter monitors the public grid automatically. Whenever there’s inconsistency in the electric grid (for example, a grid switch-off or interruption), this solar inverter immediately interrupts the power supply in the grid.   

black and white solar panels
  • How Grid Monitoring Works in the Fronius Symo

Grid monitoring utilises voltage monitoring, frequency monitoring, and monitoring islanding conditions. A real-time display of the grid’s power output and stability feeds information to the inverter, automatically adjusting its operation to ensure this stability.

aerial view of city buildings during daytime
  • Load Factor Monitoring and Interruptions 

The Fronius Symo monitors load factors by calculating active and reactive power over time, displaying instantaneous and historical graphic statistics such as power consumption curves and data. 

It swiftly handles short interruptions in its supply, effectively eliminating standby losses. When there is a significant problem, it displays an error code you can use to receive technical solutions on the web interface. 

brown and white concrete house

Grid monitoring information is available on a control panel with a visual display. You should consult a qualified solar installer if you wish to do this.

  • Temperature Control 

The Fronius inverter features an engineering marvel in its temperature control system. If the inverter temperature exceeds a specific value, the inverter derates automatically to ensure operator safety.  

The cause of high inverter temperature is often when the device is installed in a control cabinet without proper heat dissipation or in an area with a high ambient temperature. 

blue solar panel on green grass field near brown rocky mountain during daytime

Fronius Symo Solar Inverter Technical Specifications 

The datasheets below provide a comprehensive overview of each Fronius Symo model’s technical specifications and general info. If you want a snapshot of a particular model’s specs, you can also refer to the data provided on the Fronius website.

Input DataSYMO 3.0-3-SSYMO 3.7-3-SSYMO 4.5-3-SSYMO 3.0-3-M SYMO 3.7-3-MSYMO 4.5-3-M
Number of MPP trackers111222
Max. input current
(Idc max)
16.0 A16.0 A16.0 A16.0 A / 16.0 A16.0 A / 16.0 A16.0 A / 16.0 A
Max. short circuit current, module array24.0 A24.0 A24.0 A24.0 A / 24.0 A24.0 A / 24.0 A24.0 A / 24.0 A
DC input voltage range
(Umpp min – Umpp max)
150 – 1000 V150 – 1000 V150 – 1000 V150 – 1000 V150 – 1000 V150 – 1000 V
Feed-in start voltage
(Udc start)
200 V200 V200 V200 V200 V200 V
Usable MPP voltage range150 – 800 V150 – 800 V150 – 800 V150 – 800 V150 – 800 V150 – 800 V
Number of DC connections3332+22+22+2
Max. PV generator power
(Pdc max
6.0 kW peak7.4 kW peak9.0 kW peak6.0 kW peak7.4 kW peak9.0 kW peak
Output DataSYMO 3.0-3-SSYMO 3.7-3-SSYMO 4.5-3-SSYMO 3.0-3-M SYMO 3.7-3-MSYMO 4.5-3-M
AC nominal output (Pac,r)3000 W 3700 W 4500 W 3000 W 3700 W 4500 W
Max. output power
(Pac max)
3000 W 3700 W 4500 W 3000 W 3700 W 4500 W
AC output current
(Iac nom)
4.3 A 5.3 A 6.5 A 4.3 A 5.3 A6.5 A
Grid connection (voltage range)3~NPE 400 V / 230 V or 3~NPE 380 V / 220 V (+20 % / -30 %)3~NPE 400 V / 230 V or 3~NPE 380 V / 220 V (+20 % / -30 %)3~NPE 400 V / 230 V or 3~NPE 380 V / 220 V (+20 % / -30 %)3~NPE 400 V / 230 V or 3~NPE 380 V / 220 V (+20 % / -30 %)3~NPE 400 V / 230 V or 3~NPE 380 V / 220 V (+20 % / -30 %)3~NPE 400 V / 230 V or 3~NPE 380 V / 220 V (+20 % / -30 %)
Frequency
(fmin – fmax)
50 Hz / 60 Hz
(45 – 65 Hz)
50 Hz / 60 Hz
(45 – 65 Hz)
50 Hz / 60 Hz
(45 – 65 Hz)
50 Hz / 60 Hz
(45 – 65 Hz)
50 Hz / 60 Hz
(45 – 65 Hz)
50 Hz / 60 Hz
(45 – 65 Hz)
Total harmonic distortion< 3 %< 3 %< 3 %< 3 %< 3 %< 3 %
Power factor
(cos φac,r)
0.7 – 1 ind. / cap.0.7 – 1 ind. / cap.0.7 – 1 ind. / cap.0.8 – 1 ind. / cap.0.8 – 1 ind. / cap.0.8 – 1 ind. / cap.

General DataSYMO (3.0-3-S, 3.7-3-S, 4.5-3-S)SYMO (3.0-3-M, 3.7-3-M, 4.5-3-M)
Dimensions (H x W x D)645 x 431 x 204 mm645 x 431 x 204 mm
Weight16.0 kg19.9 kg
Degree of protectionIP 65IP 65
Protection class11
Overvoltage category (DC / AC)2 / 32 / 3
Night-time consumption< 1 W< 1 W
Inverter designTransformerlessTransformerless
CoolingRegulated air coolingRegulated air cooling
InstallationIndoor and outdoor installationIndoor and outdoor installation
Ambient temperature range-25 – +60 °C-25 – +60 °C
Permitted humidity0 – 100 %0 – 100 %
Max. altitude2,000 m / 3,400 m
(unrestricted / restricted voltage range)
2,000 m / 3,400 m
(unrestricted / restricted voltage range)
DC connection technology3x DC+ and 3x DC- screw terminals 2.5 – 16 mm² 4x DC+ and 4x DC- screw terminals 2.5 – 16 mm² (16 mm² without ferrules)
AC connection technology5-pole AC screw terminals 2.5 – 16 mm² 5-pin AC screw terminals 2.5 – 16 mm² (16 mm² without ferrules)
Certificates and compliance with standardsÖVE / ÖNORM E 8001-4-712, DIN V VDE 0126-1-1/A1, VDE AR N 4105, IEC 62109-1/-2, IEC 62116, IEC 61727, AS 3100, AS 4777-2, AS 4777-3, CER 06-190, G83/2, UNE 206007-1, SI 4777 1), CEI 0-21 1) , NRS 097ÖVE / ÖNORM E 8001-4-712, DIN V VDE 0126-1-1/A1, VDE AR N 4105, IEC 62109-1/-2, IEC 62116, IEC 61727, AS 3100, AS 4777-2, AS 4777-3, CER 06-190, G83/2, UNE 206007-1, SI 4777 1), CEI 0-21 1) , NRS 097

EFFICIENCYSYMO 3.0-3-SSYMO 3.7-3-SSYMO 4.5-3-SSYMO 3.0-3-MSYMO 3.7-3-MSYMO 4.5-3-M
Max. efficiency
(PV – grid)
98.0 %98.0 %98.0 %98.0 %98.0 %98.0 %
European efficiency (ηEU)96.2 %96.7 %97.0 %96.5 %96.9 %97.2 %
MPP adaptation efficiency99.9 %99.9 %99.9 %99.9 %99.9 %99.9 %
PROTECTIVE DEVICESSYMO 3.0-3-SSYMO 3.7-3-SSYMO 4.5-3-SSYMO 3.0-3-MSYMO 3.7-3-MSYMO 4.5-3-M
DC insulation measurementYesYesYesYesYesYes
Overload behaviourOperating point shift, power limitationOperating point shift, power limitationOperating point shift, power limitationOperating point shift, power limitationOperating point shift, power limitationOperating point shift, power limitation
DC disconnectorYesYesYesYesYesYes
Reverse polarity protectionYesYesYesYesYesYes
INTERFACESSYMO 3.0-3-SSYMO 3.7-3-SSYMO 4.5-3-SSYMO 3.0-3-MSYMO 3.7-3-MSYMO 4.5-3-M
WLAN / Ethernet LANFronius Solar.web, Modbus TCP SunSpec, Fronius Solar API (JSON)Fronius Solar.web, Modbus TCP SunSpec, Fronius Solar API (JSON)Fronius Solar.web, Modbus TCP SunSpec, Fronius Solar API (JSON)Fronius Solar.web, Modbus TCP SunSpec, Fronius Solar API (JSON)Fronius Solar.web, Modbus TCP SunSpec, Fronius Solar API (JSON)Fronius Solar.web, Modbus TCP SunSpec, Fronius Solar API (JSON)
6 inputs and 4 digital inputs/outputsInterface to ripple control receiverInterface to ripple control receiverInterface to ripple control receiverInterface to ripple control receiverInterface to ripple control receiverInterface to ripple control receiver
USB (A socket)Datalogging, inverter update via USB flash driveDatalogging, inverter update via USB flash driveDatalogging, inverter update via USB flash driveDatalogging, inverter update via USB flash driveDatalogging, inverter update via USB flash driveDatalogging, inverter update via USB flash drive
2x RS422
(RJ45 socket)
Fronius Solar NetFronius Solar NetFronius Solar NetFronius Solar NetFronius Solar NetFronius Solar Net
Signalling outputEnergy management (potential-free relay output)Energy management (potential-free relay output)Energy management (potential-free relay output)Energy management (potential-free relay output)Energy management (potential-free relay output)Energy management (potential-free relay output)
Datalogger and Web serverIncludedIncludedIncludedIncludedIncludedIncluded
External inputS0-Meter Interface / Input for overvoltage protectionS0-Meter Interface / Input for overvoltage protectionS0-Meter Interface / Input for overvoltage protectionS0-Meter Interface / Input for overvoltage protectionS0-Meter Interface / Input for overvoltage protectionS0-Meter Interface / Input for overvoltage protection
RS485Modbus RTU SunSpec or meter connectionModbus RTU SunSpec or meter connectionModbus RTU SunSpec or meter connectionModbus RTU SunSpec or meter connectionModbus RTU SunSpec or meter connectionModbus RTU SunSpec or meter connection

TECHNICAL DATA FRONIUS SYMO (5.0-3-M, 6.0-3-M, 7.0-3-M, 8.2-3-M)

INPUT DATASYMO 5.0-3-MSYMO 6.0-3-MSYMO 7.0-3-MSYMO 8.2-3-M
Number of MPP trackers2222
Max. input current
(Idc max)
16.0 A / 16.0 A16.0 A / 16.0 A16.0 A / 16.0 A16.0 A / 16.0 A
Max. short circuit current, module array24.0 A / 24.0 A24.0 A / 24.0 A24.0 A / 24.0 A24.0 A / 24.0 A
DC input voltage range
(Umpp min – Umpp max)
150 – 1000 V150 – 1000 V150 – 1000 V150 – 1000 V
Feed-in start voltage
(Udc start)
200 V200 V200 V200 V
Usable MPP voltage range150 – 800 V150 – 800 V150 – 800 V150 – 800 V
Number of DC connections2+22+22+22+2
Max. PV generator power (Pdc max10.0 kW peak12.0 kW peak14.0 kW peak16.4 kW peak

OUTPUT DATASYMO 5.0-3-MSYMO 6.0-3-MSYMO 7.0-3-MSYMO 8.2-3-M
AC nominal output (Pac,r)5000 W6000 W7000 W8200 W
Max. output power (Pac max)5000 VA6000 VA7000 VA8200 VA
AC output current
(Iac nom)
7.2 A8.7 A10.1 A11.8 A
Grid connection (voltage range)3-NPE 400 V / 230 V or 3~NPE 380 V / 220 V (+20 % / -30 %)3-NPE 400 V / 230 V or 3~NPE 380 V / 220 V (+20 % / -30 %)3-NPE 400 V / 230 V or 3~NPE 380 V / 220 V (+20 % / -30 %)3-NPE 400 V / 230 V or 3~NPE 380 V / 220 V (+20 % / -30 %)
Frequency
(fmin – fmax)
50 Hz / 60 Hz
(45 – 65 Hz)
50 Hz / 60 Hz
(45 – 65 Hz)
50 Hz / 60 Hz
(45 – 65 Hz)
50 Hz / 60 Hz
(45 – 65 Hz)
Total harmonic distortion< 3 %< 3 %< 3 %< 3 %
Power factor
(cos φac,r)
0.85 – 1 ind. / cap.0.85 – 1 ind. / cap.0.85 – 1 ind. / cap.0.85 – 1 ind. / cap.

GENERAL DATASYMO (5.0-3-M, 6.0-3-M, 7.0-3-M, 8.2-3-M)
Dimensions (H x W x D)645 x 431 x 204 mm
Weight21.9 kg
Degree of protectionIP 65
Protection class1
Overvoltage category (DC / AC)2 / 3
Night-time consumption< 1 W
Inverter designTransformerless
CoolingRegulated air cooling
InstallationIndoor and outdoor installation
Ambient temperature range-25 – +60 °C
Max. altitude2,000 m / 3,400 m
(unrestricted / restricted voltage range)
DC connection technology 4x DC+ and 4x DC- screw terminals 2.5 – 16 mm²
(16 mm² without ferrules)
AC connection technolog5-pin AC screw terminals 2.5 – 16 mm²
(16 mm² without ferrules)
Certificates and compliance with standardsÖVE / ÖNORM E 8001-4-712, DIN V VDE 0126-1-1/A1, VDE AR N 4105, IEC 62109-1/-2, IEC 62116, IEC 61727, AS 3100, AS 4777-2, AS 4777-3, CER 06-190, G83/2, UNE 206007-1, SI 4777, CEI 0-21, NRS 097

TECHNICAL DATA FRONIUS SYMO (5.0-3-M, 6.0-3-M, 7.0-3-M, 8.2-3-M)

EFFICIENCYSYMO 5.0-3-MSYMO 6.0-3-MSYMO 7.0-3-MSYMO 8.2-3-M
Max. efficiency
(PV – grid)
98.0 %98.0 %98.0 %98.0 %
European efficiency (ηEU)97.3 % 97.5 % 97.6 %97.7 %
MPP adaptation efficiency99.9 %99.9 %99.9 %99.9 %
PROTECTIVE DEVICES SYMO 5.0-3-MSYMO 6.0-3-MSYMO 7.0-3-MSYMO 8.2-3-M
DC insulation measurementYesYesYesYes
Overload behaviourOperating point shift, power limitationOperating point shift, power limitationOperating point shift, power limitationOperating point shift, power limitation
DC disconnectorYesYesYesYes
Reverse polarity protectionYesYesYesYes
INTERFACESSYMO 5.0-3-MSYMO 6.0-3-MSYMO 7.0-3-MSYMO 8.2-3-M
WLAN / Ethernet LANFronius Solar.web, Modbus TCP SunSpec, Fronius Solar API (JSON)Fronius Solar.web, Modbus TCP SunSpec, Fronius Solar API (JSON)Fronius Solar.web, Modbus TCP SunSpec, Fronius Solar API (JSON)Fronius Solar.web, Modbus TCP SunSpec, Fronius Solar API (JSON)
6 inputs and 4 digital inputs/outputsInterface to ripple control receiverInterface to ripple control receiverInterface to ripple control receiverInterface to ripple control receiver
USB (A socket)Datalogging, inverter update via USB flash driveDatalogging, inverter update via USB flash driveDatalogging, inverter update via USB flash driveDatalogging, inverter update via USB flash drive
2x RS422 (RJ45 socket)Fronius Solar NetFronius Solar NetFronius Solar NetFronius Solar Net
Signalling outputEnergy management (potential-free relay output)Energy management (potential-free relay output)Energy management (potential-free relay output)Energy management (potential-free relay output)
Datalogger and WebserverIncludedIncludedIncludedIncluded
External inputS0-Meter Interface / Input for overvoltage protectionS0-Meter Interface / Input for overvoltage protectionS0-Meter Interface / Input for overvoltage protectionS0-Meter Interface / Input for overvoltage protection
RS485Modbus RTU SunSpec or meter connectionModbus RTU SunSpec or meter connectionModbus RTU SunSpec or meter connectionModbus RTU SunSpec or meter connection

TECHNICAL DATA FRONIUS SYMO (10.0-3-M, 12.5-3-M, 15.0-3-M, 17.5-3-M, 20.0-3-M)

INPUT DATA SYMO 10.0-3-M SYMO 12.5-3-M SYMO 15.0-3-M SYMO 17.5-3-M SYMO 20.0-3-M
Number of MPP trackers22222
Max. input current
(Idc max)
27.0 A / 16.5 A27.0 A / 16.5 A33.0 A / 27.0 A33.0 A / 27.0 A33.0 A / 27.0 A
Max. usable input current total
(Idc max 1 + Idc max 2)
43.5 A43.5 A51.0 A51.0 A51.0 A
Max. short circuit current, module array40.5 A / 24.8 A40.5 A / 24.8 A49.5 A / 40.5 A49.5 A / 40.5 A49.5 A / 40.5 A
DC input voltage range
(Umpp min – Umpp max)
200 – 1000 V200 – 1000 V200 – 1000 V200 – 1000 V200 – 1000 V
Feed-in start voltage
(Udc start)
200 V200 V200 V200 V200 V
Usable MPP voltage range200 – 800 V200 – 800 V200 – 800 V200 – 800 V200 – 800 V
Number of DC connections3+33+33+33+33+3
Max. PV generator output (Pdc max15.0 kW peak18.8 kW peak 22.5kWpeak 26.3 kW peak30.0 kW peak
OUTPUT DATA SYMO 10.0-3-M SYMO 12.5-3-M SYMO 15.0-3-M SYMO 17.5-3-M SYMO 20.0-3-M
AC nominal output (Pac,r) 10000 W 12500 W 15000 W 17500 W 20000 W
Max. output power (Pac max)10000 VA 12500 VA 15000 VA 17500 VA 20000 VA
AC output current
(Iac nom)
14.4 A 18.0 A 21.7 A25.3 A 28.9 A
Grid connection
(voltage range)
3-NPE 400 V / 230 V or 3~NPE 380 V / 220 V (+20 % / -30 %)3-NPE 400 V / 230 V or 3~NPE 380 V / 220 V (+20 % / -30 %)3-NPE 400 V / 230 V or 3~NPE 380 V / 220 V (+20 % / -30 %)3-NPE 400 V / 230 V or 3~NPE 380 V / 220 V (+20 % / -30 %)3-NPE 400 V / 230 V or 3~NPE 380 V / 220 V (+20 % / -30 %)
Frequency
(fmin – fmax)
50 Hz / 60 Hz (45 – 65 Hz)50 Hz / 60 Hz (45 – 65 Hz)50 Hz / 60 Hz (45 – 65 Hz)50 Hz / 60 Hz (45 – 65 Hz)50 Hz / 60 Hz (45 – 65 Hz)
Total harmonic distortion1.8 % 2.0 % 1.5 % 1.5 % 1.3 %
Power factor (cos φac,r)0 – 1 ind. / cap.0 – 1 ind. / cap.0 – 1 ind. / cap.0 – 1 ind. / cap.0 – 1 ind. / cap.
GENERAL DATA SYMO 10.0-3-M SYMO 12.5-3-M SYMO 15.0-3-M SYMO 17.5-3-M SYMO 20.0-3-M
Dimensions (HxWxD)725 x 510 x 225 mm725 x 510 x 225 mm725 x 510 x 225 mm725 x 510 x 225 mm725 x 510 x 225 mm
Weight34.8 kg34.8 kg43.4 kg43.4 kg43.4 kg
Degree of protectionIP 66IP 66IP 66IP 66IP 66
Protection class11111
Overvoltage category
(DC / AC)
2 / 32 / 32 / 32 / 32 / 3
Night-time consumption< 1 W< 1 W< 1 W< 1 W< 1 W
Inverter designTransformerlessTransformerlessTransformerlessTransformerlessTransformerless
CoolingRegulated air coolingRegulated air coolingRegulated air coolingRegulated air coolingRegulated air cooling
InstallationIndoor and outdoor Indoor and outdoorIndoor and outdoorIndoor and outdoorIndoor and outdoor
Ambient temperature range-40°C – +60°C-40°C – +60°C-40°C – +60°C-40°C – +60°C-40°C – +60°C
Permitted humidity0 – 100 %0 – 100 %0 – 100 %0 – 100 %0 – 100 %
Max. altitude2,000 m / 3,400 m (unrestricted / restricted voltage range)2,000 m / 3,400 m (unrestricted / restricted voltage range)2,000 m / 3,400 m (unrestricted / restricted voltage range)2,000 m / 3,400 m (unrestricted / restricted voltage range)2,000 m / 3,400 m (unrestricted / restricted voltage range)
DC connection technology6x DC+ and 6x DC- screw terminals 2.5 – 16 mm²6x DC+ and 6x DC- screw terminals 2.5 – 16 mm²6x DC+ and 6x DC- screw terminals 2.5 – 16 mm²6x DC+ and 6x DC- screw terminals 2.5 – 16 mm²6x DC+ and 6x DC- screw terminals 2.5 – 16 mm²
AC connection technology5-pin AC screw terminals 2.5 – 16 mm²5-pin AC screw terminals 2.5 – 16 mm²5-pin AC screw terminals 2.5 – 16 mm²5-pin AC screw terminals 2.5 – 16 mm²5-pin AC screw terminals 2.5 – 16 mm²
Certificates and compliance with standardsÖVE / ÖNORM E 8001-4-712, DIN V VDE 0126-1-1/A1, VDE AR N 4105, IEC 62109-1/-2, IEC 62116, IEC 61727, AS 3100, AS 4777-2, AS 4777-3, CER 06-190, G83/2, UNE 206007-1, SI 4777, CEI 0-16, CEI 0-21, NRS 097ÖVE / ÖNORM E 8001-4-712, DIN V VDE 0126-1-1/A1, VDE AR N 4105, IEC 62109-1/-2, IEC 62116, IEC 61727, AS 3100, AS 4777-2, AS 4777-3, CER 06-190, G83/2, UNE 206007-1, SI 4777, CEI 0-16, CEI 0-21, NRS 097ÖVE / ÖNORM E 8001-4-712, DIN V VDE 0126-1-1/A1, VDE AR N 4105, IEC 62109-1/-2, IEC 62116, IEC 61727, AS 3100, AS 4777-2, AS 4777-3, CER 06-190, G83/2, UNE 206007-1, SI 4777, CEI 0-16, CEI 0-21, NRS 097ÖVE / ÖNORM E 8001-4-712, DIN V VDE 0126-1-1/A1, VDE AR N 4105, IEC 62109-1/-2, IEC 62116, IEC 61727, AS 3100, AS 4777-2, AS 4777-3, CER 06-190, G83/2, UNE 206007-1, SI 4777, CEI 0-16, CEI 0-21, NRS 097ÖVE / ÖNORM E 8001-4-712, DIN V VDE 0126-1-1/A1, VDE AR N 4105, IEC 62109-1/-2, IEC 62116, IEC 61727, AS 3100, AS 4777-2, AS 4777-3, CER 06-190, G83/2, UNE 206007-1, SI 4777, CEI 0-16, CEI 0-21, NRS 097

TECHNICAL DATA FRONIUS SYMO (10.0-3-M, 12.5-3-M, 15.0-3-M, 17.5-3-M, 20.0-3-M)

EFFICIENCYSYMO 10.0-3-MSYMO 12.5-3-M SYMO 15.0-3-MSYMO 17.5-3-MSYMO 20.0-3-M
Max. efficiency
(PV – grid)
98.0 %98.0 %98.1 %98.1 %98.1 %
European efficiency (ηEU)97.4 % 97.6 % 97.8 % 97.8 %97.9 %
MPP adaptation efficiency> 99.9 %> 99.9 %> 99.9 %> 99.9 %> 99.9 %
PROTECTIVE DEVICESSYMO 10.0-3-MSYMO 12.5-3-M SYMO 15.0-3-MSYMO 17.5-3-MSYMO 20.0-3-M
DC insulation measurementYesYesYesYesYes
Overload behaviourOperating point shift, power limitationOperating point shift, power limitationOperating point shift, power limitationOperating point shift, power limitationOperating point shift, power limitation
DC disconnectorYesYesYesYesYes
Reverse polarity protectionYesYesYesYesYes
INTERFACES SYMO 10.0-3-MSYMO 12.5-3-M SYMO 15.0-3-MSYMO 17.5-3-MSYMO 20.0-3-M
WLAN / Ethernet LANFronius Solar.web, Modbus TCP SunSpec, Fronius Solar API (JSON)Fronius Solar.web, Modbus TCP SunSpec, Fronius Solar API (JSON)Fronius Solar.web, Modbus TCP SunSpec, Fronius Solar API (JSON)Fronius Solar.web, Modbus TCP SunSpec, Fronius Solar API (JSON)Fronius Solar.web, Modbus TCP SunSpec, Fronius Solar API (JSON)
6 inputs and 4 digital inputs/outputsInterface to ripple control receiverInterface to ripple control receiverInterface to ripple control receiverInterface to ripple control receiverInterface to ripple control receiver
USB (type A socket)Datalogging, inverter update via USB flash driveDatalogging, inverter update via USB flash driveDatalogging, inverter update via USB flash driveDatalogging, inverter update via USB flash driveDatalogging, inverter update via USB flash drive
2x RS422 (RJ45-socket)Fronius Solar NetFronius Solar NetFronius Solar NetFronius Solar NetFronius Solar Net
Signalling outputEnergy management (potential-free relay output)Energy management (potential-free relay output)Energy management (potential-free relay output)Energy management (potential-free relay output)Energy management (potential-free relay output)
Datalogger and WebserverIncludedIncludedIncludedIncludedIncluded
External inputS0-Meter Interface / Input for overvoltage protectionS0-Meter Interface / Input for overvoltage protectionS0-Meter Interface / Input for overvoltage protectionS0-Meter Interface / Input for overvoltage protectionS0-Meter Interface / Input for overvoltage protection
RS485Modbus RTU SunSpec or meter connectionModbus RTU SunSpec or meter connectionModbus RTU SunSpec or meter connectionModbus RTU SunSpec or meter connectionModbus RTU SunSpec or meter connection

What is the Fronius Symo Solar Inverter’s Output Capacity?

The inverter’s output capacity varies according to each of the models. The output capacity for each model can be determined from its name. 

For instance, in SYMO 12.5-3-M, the ‘12.5’ indicates that the maximum output voltage for this inverter is 12500 VA.

aerial view of green grass field during daytime
  • Fronius Symo Input Voltage 

The inverter’s input voltage range is 220 – 253 V. It’s suitable for installation in tandem with existing electrical systems. The inverter monitors grid stability and facilitates up to 100% active power when detecting a fault in the service feed. 

What is the Fronius Symo Solar Inverter’s Efficiency?

The Fronius inverter’s efficiency rating is above 98%. This exceeds the general standard of 95% in most residential inverters. 

windmill on grass field during golden hour

How Many MPP Trackers does the Fronius Symo Solar Inverter have?

Only the SYMO 3.0-3-S, SYMO 3.7-3-S, and SYMO 4.5-3-S contain 1 MMPT. The remaining Symo range (4.5 – 20) has 2 MPP trackers for every inverter. 

MPP (Maximum Power Point) technology is a unique component of how inverters work

Historically, many solar panels were directly connected to the battery storage, often requiring a separate battery inverter. The battery’s voltage is partially returned as power to the inverter (and not back to the panel). These changes resulted in enormous losses to solar panel efficiency and excess solar energy.

But MPP technology can find its peak in energy points despite shading attributed to low temperature, defective modules, bird droppings, leaves or branches. For example, a 3000 mAh/W power module can obtain a maximum power point of 0.55 V @ 0.4 A for 12 volts, so about 11 watts. You can also have a single MPPT input. 

Does the Fronius Symo Inverter come with an Internal DC Circuit Breaker?

Yes, the short circuit current threshold for the Fronius Symo is 24.0 A.

However, for the SYMO 10.0-3-M SYMO 12.5-3-M, the short circuit current is 40.5 and 24.8 A for MPP1 and MPP2, respectively.

Moreover, the short circuit current for the SYMO 15.0-3-M SYMO 17.5-3-M SYMO 20.0-3-M is 49.5 and 40.5 A for MPP1 and MPP2, respectively. 

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Fronius Symo Key Features

Fronius inverters have an incredible array of features!

  • It’s Transformerless 

The Fronius inverter has no transformer. The lack of a transformer reduces the inverter’s weight and size, making installing these solar panels a breeze.

Being transformerless also makes maintenance and repair work more convenient and affordable. The Fronius factory ensures that the inverter has no mechanical contact parts that require lubrication. 

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  • SnapINverter Technology 

SnapINverter inverters are easier to install and service because their mounting system is separate from the power-stage component. This means that one part will be safely independent when installing or maintaining the other. 

A unique feature in the design is that the area where the connections are made is separate from the part of the inverter that holds the power-stage components. Both are installed individually.

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Wall bracket installation with innovative hinged technology is quite simple. The light connection area and cables are fitted to the wall first. Next, a power stage set is placed in the wall bracket. 

Finally, an inverter is secured in place, and it isn’t necessary to remove the entire inverter for servicing. Instead, the power stage set can be changed. Again, this work can be accomplished without removing any cabling from the wall. 

  • Integrated Data Communication

Fronius is the first inverter manufacturer to enable data communication and web access. The inverter has built-in interfaces for energy management, network connections, and web access, among others. 

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The inverter implements various communication protocols, including Modbus TCP, Modbus RTU, and Fronius Solar API (JSON). The open communication protocols can be used in parallel with existing equipment. 

  • Superflex Design

The Fronius SuperFlex Design is a collection of technical performance attributes that allow you to design your photovoltaic (solar panels) system in a simple and remarkably flexible fashion. You can customise the system to any number of shapes and sizes to meet your specific needs.

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SuperFlex is differentiated from the previous design by its two multi-phase power trackers that keep the system voltage high and by the voltage range of its DC inputs, which can accept the entire output of the inverter.

Fronius inverters are compatible with most PV system planning scenarios despite varying roof orientations and shading. The only restriction is using a single inverter model for every system. 

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  • Dynamic Peak Manager 

Dynamic Peak Tracking is an algorithm that scans every grid section instead of reviewing a small portion of the characteristic curve. Unlike other MPP tracking algorithms, it automatically examines the intersection of the characteristic curves and the global maximum power point (GMPP) if it exists, regardless of partial shading in any given area.

  • Smart-grid Ready

Fronius Stored Energy Smart Inverters are engineered to meet the challenges of the smart grid. They employ advanced Smart Grid features that enable optimal reactive and sustainable power levels. A series of smart functions, known as Advanced Grid Features, such as DC string fusing, are built into the inverters for optimum performance.

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The Fronius PV inverters provide functions that help make the operation of an off-grid power system more stable and reliable. These features, such as the welding transformers, help ensure that even when the capacity of a PV system is high, it won’t unexpectedly cut the power fed into the grid. 

If your solar panels have a Fronius PV inverter, you can also feed energy into the grid in a controlled fashion to prevent overloading the connected infrastructure. You can even use Fronius inverters to self-consume power from your PV system to raise the revenue from selling excess energy back into the grid.  

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  • Zero Feed-in 

The Fronius inverter supplies the household with energy first with dynamic power reduction. It then reduces the output to the maximum feed-in permitted by the grid operator.

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And with Fronius inverters, zero feed-in is possible, meaning that no PV power is supplied to the grid. You can alter this by enabling a setting on the inverter’s web interface.

  • Active Cooling 

Active cooling uses one or more fans to prevent hot spots and regulate airflow inside the inverter, keeping the temperature low. This increases service life and improves efficiency and profitability while delivering grid-compatible AC electricity and external relay control. This active cooling system makes it one of the best inverters on the market.  

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  • Key Takeaways

The transformerless Fronius inverter features a wide input voltage range for its two MPP trackers ensuring design flexibility and control over excess power. The Fronius SnapINverter design is also light and easy to install. 

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The communication package included as standard, with WLAN, energy management, several interfaces, and much more, allows the Fronius Symo inverter to communicate with the user, the PV system, and the grid. 

Customers generally predict a solar panels (PV/solar) system to produce energy at a minimal maintenance cost for around 25-30 years. But the likelihood of that depends on the quality and reliability of the inverter. 

What is the Fronius Symo Solar Inverter’s Warranty?

Fronius inverters have a longstanding reputation for quality and reliability. They’re far more likely to outlast other inverter brands and rarely suffer system failures.

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Upon purchase, customers can earn a two-year warranty on all Fronius inverters in select countries. The company also provides a five-year warranty period in countries like Australia. Lastly, they offer a ten-month warranty online after the customer has registered their inverter. 

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Fronius provides excellent customer service. If any of its products exhibit issues, the company generally sends a replacement within 3-5 business days of receiving the damaged product.

Fronius Symo comes with four warranty categories:

  • Fronius Inverters Standard Warranty

The standard warranty extends the initial two-year warranty by an additional five years. All material costs, servicing, and transport are equally covered in the standard warranty.  

  • Fronius Inverters Warranty Plus

The Fronius Warranty Plus extends the standard two-year warranty by three years, providing complete peace of mind with five years of coverage. In this period, all expenses incurred due to significant material failure and servicing are covered by the warranty.

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  • Fronius Inverters Warranty Extension

This extension is designed so that system owners can protect themselves against risks. If a customer claims, Fronius provides the relevant materials free of charge based on the solar industry standards. 

  • Fronius Inverters Warranty Extension Plus

The Fronius Warranty Extension Plus protects you by covering you in the event of a claim. Fronius also covers the cost of removing and installing any replacement parts of the Fronius inverters, as well as the cost of transporting them to your door. 

Is the Fronius Symo Solar Inverter Reliable? Is the Solar Inverter Safe?

Fronius is a prominent name in the inverter manufacturing sector with more than two decades of experience under its belt. The quality and reliability of an inverter system are based on several factors.

This section delves into the design, product testing, and other tangibles that assess the quality and reliability of the Fronius solar systems.   

  • Product Testing

Fronius solar inverters’ product testing includes mechanical, thermal, and electrical simulations. Tests also cover specific inverter features, such as MPPT, DC input, DC power and grid feed. 

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The products were individually rated by the Department of Energy (DoE), the leading inverter testing and rating organisation.

Each product went through a rigorous 185 minutes type test. During that time, Fronius inverters maintained an average of 101% nominal voltage with no disconnections. You can read the results of the type test here.

  • Product Failure Rate Over Time 

The Fronius solar inverter, like other products such as the Fronius Symo Hybrid inverter, Fronius string inverters, and the Fronius Primo inverters, provides 20 years of active energy production. Over time, the product’s failure rate is the estimated number of times the inverter records a downtime within the intrinsic failure period.

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Standard 7.5 kVA Fronius Primo and Fronius Symo Hybrid inverters can remain productive for 16.7 years before reaching the deteriorating stage of their reliability lifecycle. With the Fronius Primo inverter, you can expect one significant downtime in 15-16 years by that metric.  

Is the Fronius Symo Solar Inverter CEC-Approved?

Symo inverters are durable solar inverters for Australian conditions, with a Clean Energy Certification. 

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Fronius Australia ensures that all inverters comply with the standard industry practice, making them ideal for the Australian market.

This high-performance inverter is perfect for harsh conditions and caters perfectly to the Australian climate. Installation is simple, and there are multiple modes for flexibility and ease of use. 

aerial view of green grass field during daytime

Fronius combines an energy-efficient design with numerous safety features, making it one of the most valuable solar systems for any home or business in Australia. 

Moreover, the Fronius inverter is certified under several licenses. For example, the UL 1741-2010 and 1998 compliance demonstrate that the Symo inverter complies with safety standards, can sustain grid excursions, and manage grid reliability functions. 

Other certifications include the IEEE 1547-2003, UL1699B Issue 2 -2013, and the CSA TIL M-07 Issue 1 -2013, among others.  

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Can you Retrofit a Battery to the Fronius Symo Solar Inverter?

Yes, you can certainly attach a battery to your Symo inverters. If you plan to use Fronius batteries, you can have an all-in-one solar power solution seamlessly integrated into your current setup. 

Is the Fronius Symo a High-quality and Valuable Inverter? Our Opinion

With so many solar inverter brands on the market, what makes Fronius products unique?

Here are some reasons why:

  • It’s Fully Automatic

Fronius knows its craft. The Symo inverter is ready to use right out of the box. There is no need to configure it, as this is a fully-automated process. You can adjust settings to match preferences and requirements, but changing the default configuration is unnecessary. 

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  • Easy Installation

The Fronius inverter can be easily mounted to a wall with a thin section of wood away from direct sunlight. When ordering your Fronius inverter, specify additional wood for mounting in the order form or consider using string inverters.

solar panels on green grass field under blue sky during daytime

By ordering extra wood for mounting, you can easily position your inverter anywhere in the home. However, we recommend installing it at a height of no more than two meters from the ground.  

Since the SnapINverter offers the possibility of mounting it in a space-saving manner, it’s available for design calculations for small installations with many components.  

In addition, the Fronius inverter comes with pre-installed cables for the inverter and AC combiner. You connect the precut cables to the inverter and combiner during installation. 

If you’re an existing Fronius customer, the Power Package uses the same SnapINverter installation system already familiar to you, reducing installation time and errors. 

yellow petaled tree on green grass field near cable posts

According to the manufacturer, the Fronius Symo inverter can be installed in as little as 15 minutes.  

Fronius Symo’s speedy installation means you can spend less time configuring the system and more time using it. As an added benefit, you’ll be able to test your system and enjoy its benefits in no time.

  • Maximum Flexibility in Data Communication 

The Fronius Power Package features an open protocol, ModbusPlus, that allows the system energy to be monitored and managed by other external programs like data loggers, park regulators, or energy management systems.

mountain peak

Fronius’s Solar.web software uses the Modbus system to connect to the Fronius solar inverter. This protocol allows Fronius to access the system remotely to provide the best possible technical support. 

In addition, the parallel connection allows local third-party systems to work seamlessly with Fronius software. The Solar.web portal will enable you to monitor your system through a mobile app. 

You can also install the Fronius smart meter to monitor your consumption. 

Find out more about the smart meter in this guide

  • No Need to Install a Cage 

Most inverters are quite weighty due to the nature of their components. To prevent them from falling, you may need to install a cage. 

If there are two or more inverters in a setup, there’s always a risk of one unit coming loose. And if the inverter falls in the cage, it will invariably be damaged. 

photo of three solar panels

The Fronius Symo inverter doesn’t require a cage because it’s transformerless and all components fit in a compact structure. 

Therefore, users don’t need to worry about this feature’s inverter or battery chargers falling. The inverter output, power generation, and DC electricity produced also remain the same. 

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However, the Symo inverters do possess some shortcomings, as mentioned below:

  • Noise

Many users report that noise levels can be irritating when the inverter is located in an apartment or enclosed room, particularly during peak solar production times. As a result, we recommend installing the inverter away from your living space or bedroom. 

  • Cost

The Fronius Inverter may not meet your criteria if affordability is the goal. And despite its hefty price tag, the inverter’s warranty period lags behind its competitors. 

Fronius has an established position within the solar industry and produces high-quality inverters and solutions with excellent backup power. The Fronius Symo Inverter is one of the best inverters in the industry, with superior power efficiency and various options. 

The high system voltage, wide input voltage range, and dual MPP trackers ensure maximum flexibility in system design and make the job of solar installers far more manageable. And, by AC coupling with a compatible battery, you can increase battery power. The PV point can also serve as a capable backup power.

The standard interface to the internet via WLAN or Ethernet and the ease of integrating third-party components make the Fronius one of the most communicative inverters in the solar inverter industry.

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Next Steps…

Interested in solar? Use our solar calculator below to know how much you’ll save with solar, find out what rebates you’re eligible for, and determine the positive impact your solar system will have on the environment.

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Otherwise, you can always contact us on 1300 133 556 or email us at sales@instylesolar.com.au.

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