Fronius Inverters

Symons Energy tailors each solar array we install to our client’s needs. So, the best inverter and solar panels for one client is not necessarily the best for another client.  Having said this, Fronius Inverters have ranked at the top of everyone’s list for several years. Fronius has a reputation for service, quality and reliability.

When I started in the solar industry, SMA and Aurora Power-One (now ABB) were the inverters any reputable solar company recommended. They ranked numbers one and two respectively.   Fronius was number three. Most other inverters had little or no track record.  In 2012 things changed.  Firstly, Fronius released the snap-in inverter. I will speak more of this later. Secondly, SMA moved the production of its new Sunny Boy AV series to China in 2013. Unfortunately, the residential market which seemed to trust German manufacturing over Chinese moved away from SMA and as a result, they lost many sales.  In 2018, SMA moved all its manufacturing back to Germany.  I should stress that although SMA’s AV series got off to a bad start, they are gaining in popularity. The launch of the snap in inverter and SMA’s china decision catapulted Fronius into first place.

A little History

The company started in 1945. In 1950, Günter Fronius, the founder of the company, expanded his product portfolio to include welding transformers.  All Fronius solar inverters are still engineered, designed and manufactured in Austria. With over half a century of experience in inverter (welder) design and manufacturing it’s not surprising Fronius is considered an industry leader in power conversion equipment. Fronius’s history in designing high performance welding inverters provided the ideal background for moving into the solar inverter production over two decades ago with the first Fronius solar inverter released in 1994. Fronius is now represented by subsidiaries in over 28 countries including Australia where its headquarters is in Melbourne.

Fronius Primo Inverters

The current Fronius snapINverter range, including the Primo, Symo and ECO have become the inverters of choice for many domestic and commercial solar installations.

The Fronius Primo ‘SnapINverters’ is widely regarded as the highest quality and most reliable residential string solar inverter available. A ‘string’ solar inverter refers to a string of solar panels linked together in series. String inverters are the most common type of inverter used in Europe, Australia and Asia. Fronius Primo range is used where there is single phase and comes in a range of 3kW to 8.2kW. It is a transformerless inverter or a TL inverter which gives a higher level of efficiency than conventional inverters. They are lighter, more compact and less expensive.  They use electronic switching rather than mechanical and by doing so reduce both noise and heat.

The 5kW to 8.2kW Primo inverters range features dual MPPT ports.  These ports have a high input current rating.  This allows two strings of panels to be connected in parallel. 

While heavier than most of the modern inverters available today at 21.5kg, the unique snap-in design makes installation and servicing easy.  This is one of the reasons installers like Fronius. Monitoring and setup via the large clear display and 4 multi-function buttons is considered one of the best interfaces of any inverter.

In a larger PV array, individual PV panels are connected in both series and parallel. A series-connected set of solar cells or modules is called a “string”.

Dual MPPT allows:

1. each string to be on a different angle

2. each string can face a different direction

3. each string can have a different number of panels e.g. 8 on one and 12 on the other.

4. each string can have dissimilar modules

5. better monitoring and performance.

The Primo inverters are cooled by an active cooling system using fan-forced air. Active cooling, while being a little more complex, Fronius claims that it increases the performance and reliability when compared to the more common passive cooling systems. Many believe that this is one reason behind the Fronius’ low failure rate.

Fronius Galvo Inverters

The Galvo range of inverters are between 1.5kW to 3.1kW and are single-phase transformer-based inverters. They are ideal for retrofitting small system. It must be said, Symons Energy has never installed any Fronius Galvo inverters in this range.   Most people with a small system looking at a new inverter are usually interested in replacing the panels as well as enlarging their system.  Because the rebates are on the panels and not the inverter, it is more economical to do a complete upgrade.

Fronius Symo & Eco Inverters

The Fronius Symo and Eco are three-phase inverters using the same snap-in design and available in a wide range of sizes to suit both residential and commercial applications. Symo inverters range from 3.0kW up to 20kW, while the ECO’s are available in 25kW or 27kW sizes.  They use the fan-forced active cooling system. The Eco series has a sterling reputation in the commercial market because of its high performance, reliability and advanced communication options.

Fronius Symo Hybrid

If there is a weakness in the Fronius range of inverters, it is the Symo Hybrid.  Most homes outside Europe are single phase. The Symo Hybrid is only available in 3-phase. It is also limited by only one MPPT port which means that all panels must have the same orientation.  And, the range is small, coming in a 3.0kW, 4.0kW and 5.0kW.  Of course, Symons Energy has found that more and more homes looking at installing batteries now or later are considering systems larger than the standard 6.6kW system most houses are installing.  This is particularly true for homes in rural towns.  When dealing with a 10kW to 13.2kW system we can employ 2 x 5kW Fronius Symo Hybrid inverter allowing two orientations.

Another weakness with the Fronius Symo Hybrid, is its lack of capability with many brands of battery other than Fronius. Although this is being addressed.  Fronius is due to launch a new hybrid inverter in early 2020. These new inverters, the Gen24, are to compatible with more batteries, have duel MPPT ports, a more efficient fan system, and an integrated grid backup.


We have discussed the fact that Fronius inverters are incredibly reliable. However, if a failure occurs, they usually ship replacement units in 3-5 business days. Fronius inverters are available with either 5- or 10-year warranties, depending on the location or country.

 All Fronius string inverters come with 5 years Fronius Warranty Plus. Customers can obtain an additional free, 5-year extended warranty when the inverter is registered online by logging on to This provides a total 10 warranty period.

Solar Web

If none of the above convinces you that Fronius should be your number one choice for an inverter, Solar.Web will. Wi-Fi monitoring comes standard with all inverters and can be accessed by the Solar.Web mentioned above. Everyone at Symons Energy loves how Solar.Web gives our clients a full overview of their solar installation and control over its output and function when they at home or on the move using the Fronius Solar.Web app smart phones and tablets and notebooks. The Solar.Web portal allows operators to easily and conveniently monitor, analyse and compare their photovoltaic systems. All the important data, such as output, yields and consumption, energy balance or the state of charge of your energy storage unit are clearly displayed. This keeps you informed about all aspects of your photovoltaic system, enables you to optimise your self-consumption and make considerable savings. But, and here is the exciting part, Solar.Web will also allow Symons Energy to monitor your system.  This gives Symons Energy the ability to assist you with enquiries about your installation performance.  Most consumers don’t access the more analytic information available on Solar.Web but our technicians can use this information to pinpoint any problems or deficiencies.

Solar.Web not only can give in-real time information on what is happening with your solar array but will also supply long term historical data.  It will automatically notify you and Symonds Energy of system faults and generate reports.

Fronius Solar.Web Premium is a free tool giving you all the information you get with Solar.Web but it includes a comprehensive self-consumption analysis and a permanent overview of power consumption. These include a comprehensive self-consumption analysis and a permanent overview of power consumption. It’s easy to export the data and then process it in other programs, helping you to control and optimise your energy costs. Energy storage systems can also be monitored closely, thanks to the clear visualisation. A comprehensive overview of your photovoltaic system is thus always in your grasp.

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Published Date : January, 6 2020