In Blog, Inverters, Micro Inverters & Optimisers

Fronius Inverter ReviewIt’s no overstatement to say the Fronius Primo inverter and Fronius Symo inverter has a cult following in the Australian solar market. But does the Fronius Inverter deserve its reputation? Before scrutinising the inverter, we’ll start with a brief history of the company Fronius. We’ll then have a glimpse at the mothership, Fronius International, and I’ll introduce the Fronius Australia team.

After the fluffy stuff, we’ll look at the design of the Fronius Snap Inverter series. We’ll look under the hood of the Fronius Primo, and I’ll reveal our failure rate.  I’ll then explain why a Fronius Primo SC is actually the good old Fronius ‘International’ with a fancy name. We’ll discuss the limitations of some of the Symo inverters, and we’ll wrap it up by looking at Fronius Solar Web and the Fronius Smart Meter.

About The Company

Günter Fronius

Günter Fronius started Fronius in 1945 – the same year World War 2 ended. He began by building battery car chargers in his family home in Rankleiten, Austria. In 1950 he applied his DC to AC conversion expertise to manufacture welding transformers. In the 1980’s he handed the business over to his children, Bridget and Klaus, who drove the vision of Fronius internationally.

  • In 1992, Fronius introduced a third division, Solar Energy.
  • In 2001, they made the now infamous Fronius IG inverter.
  • In 2014, they made amends for their IG inverter mishap and brought out the Fronius Primo and Fronius Symo inverters.

That’s how it all began.

Fronius International

Mrs Strauss FroniusLast year I was invited to Fronius International and had the privilege of meeting the granddaughter of Gunter Fronius and CEO of Fronius International, Mrs Strauss. It turns out you don’t get to know an Austrian businesswoman in a 2-minute chat. But judging by the way her Fronius Australian staff speak of her, she’s something special.

Although the company now has a huge international presence, it has kept its family business feel thanks to the warm and wise leadership of Mrs Strauss. Fronius radiates a positive, professional and friendly atmosphere.

Fronius International Inverters

Fronius perfectionism

The tour of Fronius Austria was impressive. Having previously lived in Austria I am acutely aware that Austrians are prudent and orderly people who respect perfectionism. This is interesting if not intimidating to witness in the day-to-day life, but to see this translate into a large-scale Research and Development Facility and Manufacturing Plant was mind-blowing. Understandably, photographs from inside the facility were not permitted. But I can share a glimpse into how impressive the facility is by sharing one of their marketing videos.

Before I visited Fronius International, I assumed these promotional videos were cleverly imagined and fabricated marketing material. Apart from the golden British voice-over and the slow-motion strutting, it is a close reflection of reality at Fronius Research and Development.

Fronius Australia

If the culture of a business is a barometer of its longevity, then Fronius Australia is here to stay. I’ve had the privilege of travelling and working with many of the key Fronius Australia staff over the last few years. Keshia, Adrian, Rod, Bella, Balaji, Sebastian, and the new player in Brisbane, Matthew, to name a few. They stand apart from their competitors. You can tell they love working for Fronius and were picked for their passion and knowledge of the industry. It’s always a pleasure having a meeting or a beer with any of them.

So an Austrian family business starts out in the dust of World War II and builds an international empire with amazing company culture and a hunger for perfection. The fluffy stuff sounds A-OK. But is the inverter any good?

Snap Inverter

Fronius Inverter Review technical

The Fronius Snap Inverter (as it is cleverly and uncommonly called) is smart and sleek. You can’t say that about every inverter. To comply with Australian & New Zealand Standards, Fronius integrates the DC Isolator onto the backplate so we don’t have to install another DC isolator beside the inverter. The integrated DC isolator not only saves on installation time and material cost, but it also makes the installation neater (ignore the conduits all over my test wall). The inverter then “snaps in” to the back plate. Shmicko. Easy and good-looking install. Everyone is happy.

Update – These days it’s fairly common for an inverter to have a built-in DC isolator. Fronius, however, was the leader of that pack.

Fronius Primo internal inverterFronius Inverter Internal Build

The Fronius inverter is an obvious product of an anally retentive production line manager. I’ve pulled apart a few inverters in my time, and I don’t think it’s just my bias that says the Fronius inverter is the neatest. You don’t get the silicone-like goop smeared all over inverters, and all wiring is neatly loomed.

I watched the assembly process when I visited the factory in Austria. It was impressive how each one was assembled by the hands of attentive Austrians who didn’t look to be in a rush.

Fronius inverter coilHowever, I did find one thing that proves beyond reasonable doubt that Austrians are not perfect. An inductor coil on the 18 amp Primo is separated from the other inductors with a piece of imperfectly wrapped insulation!

Yeah, that’s the best I’ve got.

Fronius inverter external fan

Fan Cooling

The 12 amp Fronius Primos have one external fan, while the 18 amp versions have two. All Fronius inverters also have an internal fan. High temperatures shorten the life of electronics, particularly electrolytic capacitors, so it is vital to keep inverters cool.

Fronius Inverter Running TempAs seen in this thermal image, the Fronius inverter does a particularly good job of pumping hot air out of the top of the inverter. The ABB inverter on the right only uses an internal fan. SolarEdge and Huawei don’t use a fan at all. These manufacturers might argue that the external fans are exposed to the elements and prone to failure. After three years and 1600 installations, we haven’t had an issue with a Fronius fan. And after seeing first-hand the lengths Fronius International go to with accelerated testing, I feel no reason for concern.

Warranty Claims

In reality, every electronic device has a failure rate. In the solar industry, a failure of less than 1% is acceptable. Fronius don’t tell us specifics on their failure rate, but they aim for less than .5% and say they reach that target with most of their products. All products are under 1%.

But let’s not take their word for it. After installing about 1600 Fronius inverters in three years here are our approximate failures:

Dead on Arrivals (DOA):

  • Inverters DOA:  4 out of 1600 or .25 per cent
  • Smart Meters DOA: This is mainly screws stripping in the terminals.  12 out of  1030 or 1.7 per cent.
  • Data Manager Cards DOA: 4 out of 1600 or 0.25 %

If you added all the DOA issues together, we have 20 jobs with some kind of DOA. Or a whopping 1.25% of jobs. However, DOAs are just an annoyance to the electrician on the day of installation – it does not affect the system’s uptime.

Failure after installs

  • Inverters failure after installation: 5 out of 1600 or 0.31%.
  • Data Manager Cards after installation: 3 out of 1600 or 0.18%
  • Smart Meter failure after installation: 3 out of 1030 or 0.29%

If you added all the failures together, we have had 0.68% of jobs that we have had to return to. But again, Data manager Card and Smart Meter Failures do not affect system uptime.

The all-important failure rate that affects uptime is just the inverter failures after installation, which is 0.31%.

The Fronius Primo Inverter Power Stack

The power stack is where the DC to AC conversion happens. It’s what replaced the transformer in old inverters to make inverters transformerless. The Fronius power stack uses H5 Bridge technology (a technology that SMA introduced into the market) which switches five transistors (in the form of an “H”) to chop up the DC into a 230v AC output. Fronius uses two different power stacks for their Primo inverters.

5kW Fronius Primo with 12amp Power Stack

Fronius Primo with 12 Amp Power Stack

The smaller power stack is only capable of handling 12 amps per input and is used in the Primo 3.0, Primo 4 and Primo 5.0 (otherwise known as the Fronius “International.”)

The 12 amp power stack has fewer electrolytic capacitors, inductors, transducers and film capacitors. Because it is only rated to 12 amps, it means (at least on paper), we can not put 2 strings (or groups) of panels into 1 input. This isn’t an issue with smaller inverters when we only used 16 panels, but it becomes restrictive when we want to install 24 panels on the Primo 5 International.

Fronius Primo international inverter

Fronius Primo with 18 Amp Power Stack

When we install more panels, we need a higher current so we can install 2 strings of panels into 1 input. The 18 amp power stack is used in the Primo 5.0 AU, the Primo 6, and the Primo 8.2.

The Primo 5.0 AUS has a nominal output of 4.6kW. It was introduced to Australia because, in some parts of Australia, red tape limited the size of an inverter to 4.6kW. CEC guidelines state we can only install 33% more panels than the nameplate of the inverter so the Fronius 5.0 AUS is limited to 6.1kW of panels.

The Fronius “International” Inverter

In parts of Australia that allowed a full 5kW inverter, the 5kW Fronius International became popular because it meant we could install 6.6kW of panels. (The Fronius 5.0-1 is not technically called the “Fronius International”, that’s just the name the industry adopted to differentiate it from the Fronius 5.0-1 AUS.) A poorly-kept secret was that the Fronius International was actually made with the 18 amp power stack. So while on paper we could not install 2 strings of panels in 1 input, in reality, we could. It worked well and it was compliant.

However late last year we got some devastating news. The Fronius International was going to be made as per the spec sheet, with the 12 amp tracker. But the devastation was short-lived. Fronius heard our cry and introduced the new Fronius SC. SC stands for Superior Current. The name is uncharacteristically tacky of Fronius, but we’ll learn to embrace that and for now, we’ll celebrate that we got our baby back. A full 5kW nominal inverter with an 18 amp power stack!

So now we have three different 5kW Fronius Primo inverters:

  • The Fronius Primo AUS (18 amp, 4.6kW nominal, 6.1kW input)
  • The Fronius Primo “International” ( 18 amp 12 amps, 5kw nominal, 6.6kW max panels)
  • The Fronius Primo SC  (18 superior amps, 5kW nominal, 6.6kW max panels.)

Fronius Symo Inverter

The Fronius Symo is sometimes not as flexible as we would like. The Fronius Symo 5kW, 6kW, 7kW and 8.2kW inverters are limited to 16 amps. If we want to parallel two strings of standard ≈9 amp panels into 1 MPPT of a Fronius Symo, we can, but with a poor design: we would clip the maximum power of that MPPT input.

Fronius produced a whitepaper that explained that “current oversizing” leads to annual losses of less than .75 per cent. The problem is, that study was done in Munich, which sees even less sunshine than a sheep in a paddock on the southernmost tip of New Zealand. However, I figured I could adapt the logic in sunny Brisbane with a few tweaks:

  • If we parallel 9.3 amp panels east and west, the panels wouldn’t max out at the same time, so they would be less likely to reach 16 amps.
  • If we are oversizing the inverter by 33%, the current would only be limited when the power is limited.

Because of my flawed logic, a few of our solar 8.2kW Fronius Symo systems went out with a parallel string design. When we looked back into the Fronius SolarWeb monitoring we found this:

Fronius Inverter performance

The problem with my logic was this:

  • Even east-west paralleled strings in Brisbane would come close to their specified operating current at the same time, and,
  • We normally did not significantly oversize 6, 7 or 8.2kW inverters, because we could instead just use the bigger inverter.

For the record, we rectified our mistake by simply replacing the 8.2kW Symo inverters with 10kW Symos.

The Fronius Screen

The Fronius SnapInverter may be one of the last inverters to have a screen. Most manufacturers are moving away from using inbuilt screens because of reliability issues. Instead, they are heading to online monitoring or connecting directly via your smartphone. I prefer a screen as a backup because passwords will be forgotten and it could complicate what could have otherwise been simple troubleshooting. However, in the ideal world, every inverter would be monitored online.

Fronius Solar Web

Fronius Solar Web ( is the Fronius online monitoring platform. It’s a poor reflection of the solar industry that less than 50% of Fronius inverters were ever connected to SolarWeb. Shame on you cheap-arse sales companies for delivering a half-arsed install. Connection to Solar Web should be essential. If you have a Fronius inverter that was never connected to Solar Web, an earth-fault alarm may need to be installed to meet CEC regulations. Chances are, that didn’t happen. So call your installer and give ’em what for.

Connection to Fronius Solar Web gives you an easily navigated phone app or a web browser so you can see:

  • Instantaneous solar production
  • Instantaneous household consumption (if you install the Smart Meter)
  • Day, Month, Year, and Total production data in a simple and clear format.
  • Overlaid historical consumption if you install the Smart Meter.

Fronius also goes much deeper for the installer with:

  • Historical AC voltages on each phase
  • Historical DC voltages on each tracker
  • Historical DC current on each tracker
  • Historical AC current

Having the ability to diagnose issues like high grid voltages or seasonal shading, or even just the ability to confirm panel stringing, is a huge advantage for both us and our customers.

A simple hack of the Fronius Solar Web is that you can currently get the Premium version for free. When you are logged into your Fronius Solar Web account, sign in as if you are going to pay, but when it asks you for payment, the balance owed is zero. Once signed up for premium, your historical data is extended from 3 days to unlimited. This may change in the future to require payment, but for now, it’s completely free.

Update – Premium is no longer free, but since “Solar Web” is the best monitoring platform around. The subscription to “Premium” represents fantastic value for money in my opinion. 

The Future of Solar Web

From my bias, Fronius offers the best monitoring of any inverter. But in keeping with their “shifting the limits” motto their pending revamp will include:

  • The ability to compare what your system is producing to what your system should be producing using seasonal data and current weather data.
  • A battery sizing tool.
  • Multiple Smart Meter monitoring so we can monitor your new Fronius and your existing inverter on the same platform. And for the “Jack Longy Longs” of this world who want to monitor everything.
  • Sorting abilities for companies with thousands of installs.
  • A simpler way to work out your electricity bill over specific dates – keeping your energy retailer honest!

Fronius Smart Meter

Fronius Inverter Marketing ImageFronius Inverter Performance graphThe Fronius Smart Meter is the pièce de résistance of Fronius Solar Web. The Fronius Smart Meter is a small device that we install at your switchboard to measure the power that you consume from and sell back to the grid.

All you have to do is open the Fronius Solar Web app or log in to Solar Web online. I explain more about the Fronius Smart meter in this post.

It should be noted that you only get a 2-year warranty on the Fronius Smart Meter, and Fronius do not manufacture it themselves, which kind of takes the shine off it.

Fronius Inverter Fan BoyConclusion

If I didn’t make it clear, I’m a Fronius fanboy, but for good reason. Fronius has a solid history and an impressive Austrian manufacturing facility. The Australian team reflects the culture that Gunter Fronius began and his granddaughter continues. Austrian perfectionism shines through in the build of their inverter. If needed to find fault, you could speculate that external fans, inbuilt screens, and Smart Meters may have issues in the future, but after seeing how Fronius does their accelerated testing, I think we’re pretty safe with the fans and screens. The Fronius Primo lines up every version you would want, crowned by the versatile 5kW Primo SC. While the smaller Fronius Symo can be restrictive, those restrictions can be overcome by using a 10kW Fronius Symo. Fronius Solar Web is the best and getting better, and the smart meter is the icing on the cake.

Update – Fronius has released a new series of inverters, The “Gen24” and the “Gen24 PLUS” You can read my review of the Gen24 PLUS here. These new inverters have some really cool features and if I was installing solar at my house today, this is the inverter I would be using. 

If you are looking for a quality solar system in South East Qld, contact us.

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116 Comments on Fronius Inverter Review

Davina2022 said :Guest Report 2 months ago

Hi Stephen, yes an inverter shield designed with ventilation could help reduce the noise.

    Devina Rogers said :Guest Report 9 months ago

    Hi Josh, Mark recently did a blog about heat pumps, you'll find the answer about using a relay with it in the video:

      Mike said :Guest Report 9 months ago

      Hi I have a promo 5.0-1 just installed but having a problem with getting daily info from the app . The inverter is connected to internet with a extender. Would wifi roaming help or do I need to get the premium edition. Mike.

      • 3363
      Stephen said :Guest Report one year ago

      Hi, I have a Fronius Symo 10Kw inverter. It gets quite noisy in the day. I was wondering if there's anything you'd recommend to reduce the noise a bit? (apart from replacement with a different model or moving it). I build my own PCs and I know there's a big difference in fan quality and that some fans are much quieter than others. I was wondering if the Symo fans are a standard size and if they could be swapped out for some premium fans that might be a little quieter? I was also considering installing a large inverter cover (large for better airflow) and covering with MLV (mass-loaded-vinyl) or a similar matierial to help reduce the noise. I don't mean covering completely, but still leaving gaps for ventilation. Any ideas are welcome.

        Elliot said :Guest Report 3 years ago

        Hi Martin. The answer to that is dependant on which model of Fronius inverter and which solar panels you're using. It is definitely possible if the right combination is used.

          Mark C said :administrator Report 3 years ago

          HMM. I don't like your chances of the frequency of the off grid system being stable enough. Also, where would you feed your power back into if you home is not using all the power. There is a reason the Fronius Gen 24 costs so much. Have a read my Fronius Gen24.

            Mark C said :administrator Report 4 years ago

            Hi Geoff. If you have a 10kW inverter it will only get to 10kW (or maybe about 10.2kW?) regardless of how many panels you have installed.

              Geoff said :Guest Report 4 years ago

              Hi, I have a Symo 10kw system fed by a 13kw solar array. I am trying to understand the output. If my system is producing 12kw and I am consuming 2kw does that mean I am still exporting 10kw? If so can I increase my 10kw export limit?

              • 2250
              Matthew said :Guest Report 4 years ago

              I have a grid connected primo 8.1. No battery backup. Can I get the Fronius Primo to run during the day time, full sun (during an extended or permanent blackout or perhaps move to offgrid situation) If I physically disconnect the feed in supply power and replace this with my own 12 v to 240v 800 watt inverter?

              • 4551
              Mary Grima said :Guest Report 4 years ago

              Can we put Fronius inverter on outside east facing wall. Noise of fan can be too loud. Also can we put in a box e.g. electric meter type box (With vents) to keep out of weather

              • 2170
              Martin said :Guest Report 4 years ago

              Hi, I would like to know how many solar arrays can be connected to a Fronius single phase inverter (5kw). I want to put 3 Arrays onto the roof to optimize the hrs of sun impact. Thank you Martin

              • 6155
              sam said :Guest Report 4 years ago

              My Primo inverter dead in under 5 years. waiting for replacement. what i was told the installer only can remove so i have to pay someone to remove and put a new one. I was hoping this last more than 10 year claim (like all other appliance). I still have Galvo going ok. Not sure if it will break also!

              • 33412
              martin newman brown said :Guest Report 4 years ago

              Impressed with the review for Fronius. I am think about another inverter having go from a NEDAP (Dutch) inverter that lasted about 6 3/4 years. Purchased a used SMA SB4000TB-21 from eBay last September 2019 (now having the common fault "PE Conn". So need a new one with a 10year warranty. Only snag I am in England, UK. But Fronius is in the frame to purchase. Keep Well!

              • MK42 7SQ
              Josh corley said :Guest Report 4 years ago

              Hi mark amazing write up love the work. I currently have 20 lg 330watt panels on a fronius primo 5 into. I have room for 26 panels and am looking at upgrading is it possible with the snap inverters to simply add the panels and swap the inverter to a 8.2 unit with out having to swap the base plate. Secondary since I have the smart meter can I use the 5kw inverter for a South facing array and use export limiting. Thirdly my small hot water system is about to hold my family back if I go a heat pump system can I still use the relay to control it or not recommended due to the compressor? Thanks in advance mate

              • 4740
              Mark C said :administrator Report 4 years ago

              Hey Nicholas. Yes and it's probably simple. but it depends on which inverter you were using before. EG, if it was Solar edge - then it will be difficult.

                Nicholas collins said :Guest Report 4 years ago

                Can you tell me if I can retrofit a new 5kw fronius prima to my 2013 trina multi 250w honey pv panel cheers Nicholas

                • 2800
                Mark C said :administrator Report 4 years ago

                Hi Peter, sorry for the delayed reply. I blame COVID! For a 13.2kW solar array, go with a 10kW symo. (If you haven't already gone ahead, avoid Jinko. Their warranty process is pathetic.)

                  Mark C said :administrator Report 4 years ago

                  Hi Bill, the Fronius Primo noise is from the fan - it's fairly loud in the middle of the day, you would want it outside or away from living areas. It's transformerless, so no noise from a transformer.

                    Peter said :Guest Report 4 years ago

                    Hi, Im looking at installing 40 x Jinko 330w panels, I have 3 phase power, what would be the fronius inverter that you would recommend to adequately run my system?

                    • 3844
                    Bill Donald said :Guest Report 4 years ago

                    Fronius Primo 8.2.1 Is the noise it makes just fan noise, or is there a hum, like from a transformer? It'll be on a timber wall. Fan noise probably won't be a problem, but transformer hum could transmit through the wall structure.

                    • 7276
                    Mark C said :administrator Report 4 years ago

                    Hi Oleg, this is a relatively complicated design question that I'm about to write a blog on. To work it out, multiply the operating current of the panels by 2. (figure should be about 19amps) make sure that is not more than about 1 amp higher than the max operating current of the inverter (In short, you'll need the Fronius 5kw "SC"), Then you'll probably be right assuming you are near Brisbane or further from the equator. The worst that will happen is you will clip a bit of power at lunchtime.

                      Mark C said :administrator Report 4 years ago

                      Hi Vinod, It's not superior, but it is effectively the same.

                        Oleg said :Guest Report 4 years ago

                        Hi Mark, How many panels of the size 330 kW could be paralleled to Fronius Primo inverte 5.0 kW if panels decided in three groups on the roof. Considering panel system design as 6.6 kW what will be the minimal number of panels in a group. for the best sufficient performance. Is it Ok to parallel 6,6 and 8 and get good result? Thanks Thanks

                        • 4152
                        Vinod Lumb said :Guest Report 4 years ago

                        I am looking for Fronius 5 kw primo Australian model inverter I am being told by a solar installer that international model is superior than Australian version and as Australian version is not available they are offering International model. Please advise

                        • 3148
                        Rob R said :Guest Report 4 years ago

                        Hi Mark, I'm an electrical contractor with limited knowledge on PV systems. I have been trying to get the right advise regarding replacing an inverter at my home & after reading your review you sound like the right person to ask. I currently have a single phase Orion 5Kw inverter which has died. I have 24 north facing panels in 3 rows of 8 with each row wired back to 3 individual isolators mounted beside the inverter which is located directly above the house DB, the system is about 10 years old. I have been told to replace the whole system (which I found ridiculous), but I have also been advised to use a Fronius inverter. I would like to add more panels at some stage to allow for the installation of battery storage, so with this in mind I have the following questions: Can I & should I change to a 3phase inverter? Which Fronius inverter should I use? Thanking you in advance for your help. Regards Rob

                        • 4520
                        Mark C said :administrator Report 4 years ago

                        Hi Ian, The Fronius international is fine for this. The higher current input in the SC isn't needed.

                          Ian said :Guest Report 4 years ago

                          Hi Mark, Can I have 10 North facing and 9 East facing 350 Watt panels connected to a Fronius International? Would the Fronius SC be a better set up or a waste of money?

                          • 4580
                          Mark C said :administrator Report 5 years ago

                          Hi Dane, Yes you can install 7.5kW on a 5kW Fronius, but you can't claim STC's (the rebate) so, in reality, no you can't. However.... this rule is for solar systems without batteries. If you have a battery installed, then there is a loophole and you can oversize as much as the inverter manufacturer allows.

                            Dane said :Guest Report 5 years ago

                            Hi Mark The Primo SC 5kw has a max PV Input of 7.5kW. Does mean you can install more than 6.6kW of panels? This is what an installer has suggested although he mentioned the govt rebates only apply up to 6.6kw. Thanks

                            • 6230
                            Mark C said :administrator Report 5 years ago

                            It might get a little bit over 8.2kW (possibly 8.3kW?), but I don't think I've seen them get much higher. And yes it would flat line at that figure.

                              Neville Nicholas said :Guest Report 5 years ago

                              Thanks Mark for your reply so quickly. I guess then from what you're saying the symo 8.2.3 can output more than 8.2kwt but it straight lines at 8.23. It's happened on a number of occasions according to the fronius web. So not sure why. Many thanks. Neville

                              • 3904
                              Mark C said :administrator Report 5 years ago

                              Hi Neville, It's normal to oversize an inverter by 33 percent - so I wouldn't necessarily say you've been duped. The inverter can do the job. You might lose 1 percent production annualized (accounting for winter and rainy days etc). Unless you were told that an 8.2kW inverter had a switch that would make it output 10kW. Then you've been duped!

                                Neville Nicholas said :Guest Report 5 years ago

                                Hi Mark, have a fronius 8.2.3 symo installed with 10.25kt panels which peaks out at 8.23it's. Was told the inverter could do the job. Is there a switch in the set up to allow it to be increased to 10kwt or was I dipped. Thanks Neville

                                • 3904
                                Mark Cavanagh said :administrator Report 5 years ago

                                Hi Bob. Your Fronius is not drawing from the grid. I'm not sure what would lead you to believe this, so not sure how to explain. You probably need your installer to explain your monitoring, and how solar works.

                                  Mark Cavanagh said :administrator Report 5 years ago

                                  Hi Scott, Sorry I didnt answer that part. I would assume that it has a 12 amp power stack. But it just clicked with me that your panels are so old. The current is almost definitely less than 6 amps per panel, so your design sounds fine.

                                    Paul Dale said :Guest Report 5 years ago

                                    this was a great read - thank you

                                    • 3038
                                    bob karaszkewych said :Guest Report 5 years ago

                                    Why does my Fronius Solar system only draw power from the grid and not use solar energy during the day?

                                    • 3500
                                    Scott said :Guest Report 5 years ago

                                    Thank you for your reply Mark, I really appreciate you taking the trouble to help. Are you saying that the Primo 4.0-1 has an 18 amp power stack? I just assumed as it wasn't on the list in your article, that it must be 12 amps, and that's what concerned me. I did look at the specs and noticed a few variations between the 4.0-1 and the 5.0-1, but I didn't have the knowledge to understand them. If I have misunderstood your reply and we do have a 12 amp power stack, is that suitable for our panels (24 X Sharp 180W 24v NU-SOE3)? I'll ask the installer for our monthly output estimate.

                                    • 2484
                                    Mark C said :administrator Report 5 years ago

                                    Hi Scott, What your installer says makes sense in theory, but from looking at the spec I think you would have the same build of inverter -it's just labelled different. I'm not sure why he would have changed inputs of the inverter - it sounds he would need to use both strings (MPPT's). Your installer should have given you a monthly estimated output - and you should be able to work out if it performing as expected from there.

                                      Scott Lambert said :Guest Report 5 years ago

                                      Hi Mark, We have 24 nine-year-old Sharp panels in 4 strings facing north rated at 4kW. Our Fronius 5kW inverter died recently. The installer quoted for a 5kW Primo, but I have just learned that he installed (and charged us for) a 4kW unit. I learned this when the installer came to check the system because it was producing about 30% less than it was before. The installer changed the wiring (from 1 input to 2, I think) and now it's back close to normal, but still a little lower as far as I can tell. When I asked the installer why he changed to a 4kW unit, he told me the 5kW unit is harder to drive, and we would get a lower output from that. Having read your article, I'm concerned that we should have a 5kW inverter as we have 24 panels. I'd be very grateful for your advice.

                                      • 2484
                                      Mark C said :administrator Report 5 years ago

                                      No need to unlock. It will output 5kW if the panels are producing thi. When I say parallel strings, I mean you can have 2 string into each input - or 4 string total. But that depends on the power stack. However, your installer may have set a "power factor setting" that limits the inverter to 4.5kW. This is totally different. Read the bottom section of my recent "voltage rise" blog to understand this.

                                        Jarek said :Guest Report 5 years ago

                                        I have two strings, but how to unlock this?

                                        • 41-923
                                        Mark C said :administrator Report 5 years ago

                                        Hi Jarek. In Australia, the only difference is a stamp. It's called nominal (or nameplate) output of 4.6 and it's just to keep compliant with the regulation of some countries who have a max limit of 4.6kW (nominal). In fact, they produce 5kW. So it's not even software. It's a label. The difference between some models of 5kW Fronius inverters is the PowerStack - the ability for the inverter to handle parallel strings. That's explained more clearly in my Fronius blog (with photos of what to look for internally). It's likely that both models that you are dealing with can only handle one string - or 12 amps.

                                          Jarek said :Guest Report 5 years ago

                                          Hi Mark I have Fronius Primo 4,6-1 installed this year in Poland. Now I know that with spending 50 $ more i could buy 5,0-1, but I didn't. I've read that Fronius is offering in Poland 5,0-1 with a maximum power decreased to 4,6 kW. Is that possible only with software? If it is possible in that way, is it possible that 4,6 and 5,0 are the same inverters and the only difference is the software correcting maximum output power? I'm asking because maybe I can "unlock" my extra power :) in 4,6. Do you think it's possible?

                                          • 41-923
                                          Mark C said :administrator Report 5 years ago

                                          Hi John, I think it's up to the installer to get your solarweb to work. Can you get back onto them?

                                            John said :Guest Report 5 years ago

                                            I have yet to get the solar web thing to work. What gives?

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                                            Mark C said :administrator Report 5 years ago

                                            Hey Christina, NO. All Fronius inverters are made in Austria. They may be getting mixed up with SMA.

                                              Christina said :Guest Report 5 years ago

                                              Hi Mark, I have been told by a solar installer that Fronius Primo inverters are manufactured/assembled in CHINA. Could you please tell me if this is correct. Thank you, Christina.

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                                              Mark C said :administrator Report 5 years ago

                                              The benefit you get from having a bigger inverter won't be huge, but considering all are facing north, it would be worthwhile. But it shouldn't cost much to upgrade to a 6kW Primo. If you have three phase, I would suggest you go with a symo inverter just to minimise the impact of voltage rise.

                                                Ronald said :Guest Report 5 years ago

                                                Great post Mark. We have 6.5 kW Q-cells facing north, two strings, single phase, and a 5 kW Fronius 5.1 installed. Have requested full 6.5 kW power supplied, and have been offered either Fronius 6.2 ?? or a Fronius Symo 7.0. Your thoughts would be much appreciated. Regards, Ronald

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                                                Mark C said :administrator Report 5 years ago

                                                Hi James, yes it does. The 20kW also has an external fan, and the 20kW fan would be fairly noisy - so choose a location where daytime noise won't disturb anyone.

                                                  James said :Guest Report 5 years ago

                                                  Hi Mark! Awesome post as always! Does the (Australian) Symo come with an integrated DC isolator like the Primo? (im looking at the 20) Thanks

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                                                  Mark C said :administrator Report 5 years ago

                                                  Hi Raju. The Fronius Primo isn't "battery ready" in the sense it doesn't have a battery charger in it. But you don't need a battery ready inverter for the Powerwall - because the Powerwall has its own battery charger in it. So the Powerwall will work with any standard inverter. Another way of understanding this is the Powerwall is AC coupled - not DC coupled. AC coupled connects to the output of the inverter (240v AC). DC coupled connects to the input of the inverter - or the DC power from the panels.

                                                    Raju said :Guest Report 5 years ago

                                                    Hi Mark, great blog, very informative! I'm about to sign up to a 6.6kw system with a Primo 5.0-1 'International' inverter. I was told that this inverter is battery ready (specifically, plug and play compatible with Tesla powerwall 2 and Sonnen). Is this actually the case? I have read some conflicting views on Google. Thanks so much. Raju

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                                                    Mark C said :administrator Report 5 years ago

                                                    Hi Ali, Go the 10kW inverter. With 29 Panels you'll have to parallel one string so you will be limited on the current input of the inverter. But also go the 10kW because there is no good reason to oversize an 8kW inverter with 10kW of panels. It shouldn't cost too much more to do it right. Also, get the smart meter. While it's a bit expensive on three phases, it is definitely worthwhile if you want to understand your consumption and how to further reduce your power bill.

                                                      Alli said :Guest Report 5 years ago

                                                      Hi Mark. I am interested to hear what you would believe is better (and why). We have been quoted for LG 345W Neon2 Panels x29, Fronius Primo 8.2kw inverter and a Fronius smart meter. And then for LG 345W Neon2 Panels x29 with a Fronius 10kw 3Phase INVERTER and no smart meter. I am having a hard time understanding what would be better or what the difference is and would appreciate your wisdom!

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                                                      Mark C said :administrator Report 5 years ago

                                                      Hi Natasha, first, if it's to save money on your power bill, don't install a battery. It does depend on your feed-in tariff, but I don't know anywhere in Australia where it makes good economic sense to install a battery. If it's because you want backup power in a blackout, (emergency power supply, EPS) I'd go with a Tesla PowerWall. Don't assume you have EPS with every battery - you have to specify what you want EPS. If you get a battery, I'd also recommend your install more panels so you can fully charge your battery on a cloudy day - minimum 6.6kW.

                                                        Natasha said :Guest Report 5 years ago

                                                        Hi Mark, We have a 5kw Fronius Primo inverter & 5.2kw of Jinko panels. I’m wondering if/what options are available for a battery to be installed? Thanks:) Natasha

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                                                        Mark C said :administrator Report 5 years ago

                                                        Hi Peter, I may be wrong but the 8.2 has 1 external fan and 1 internal fan (from memory). The internal fan disperses hot air around so the heat sink can collect it. The external fan blows through a chamber that is connected to the heat sink. It does a great job of expelling the air from the heat sink. No filters needed. If you got a heap of leaves on top of the inverter heat sink area you would need to get clean the leaves off (not that I've seen that happen). The 10kW and larger symo inverters have 2 external fans. That's what the test function is there for - it's just not used on the smaller inverters. (Either that or the larger inverters have more powerful fans and have 2 speeds) I don't believe there is a test for the internal fan. Fronius solar web has all the information you need to analyse if it is derating - but I wouldn't put much weight on instantaneous outputs, there are too many variables!

                                                          wayne said :Guest Report 5 years ago

                                                          Hi Mark Thanks for informative without fear or favour blogs. With renos finished i am about to resolarise. I was going Fronius hybrid for batteries later but have taken your advice on that. I am now looking at Primo 5.0 or Symo 5.0. Primo SC would allow 20 west facing panels (LG?) paralleled on one input, I could then add 8-10 east facing panels later. Whereas Symo would allow 3phase but use 2 inputs. On the one hand I would prefer using the 3phase but being able later to utilise some cheap second hand panels and harvest some morning sun would be attractive. What do you think? Thanks Wayne in Fremantle

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                                                          Peter said :Guest Report 5 years ago

                                                          Hi Mark, Great post! Few questions related to the article: 1 - Fronius 8.2kW (18A) has 2 fans and an internal fan. I assume external 2 fans drive air through back wall heatsink (dust is less/no issue just compress air clean?) and internal through electronics. How do you clean it in a dusty area and how often. Are there sufficient HEPA (or other) filters to protect electronics (especially internal fan?)? 2 - On same 18A 8.2kW Primo model you can test fans. Display suggests that you can test Fan #1 and Fan #2. If I perform tests Fan #1 nicely ramps up but when trying to test Fan #2 it is quiet (Even with an ear on it just before sunset). It seems to me that the 2 external fans are on same circuit board (hence both Fan Test #1.) How is it? Is Fan Test #2 for 3 phase or different models than 18A Primo Fronius 8.2kW? Is it possible to hear the internal fan at all? 3 - Finally. We were testing Fronius for few days (3-4) on analogue meter and it was gearing up to 8.26kW display reading at lunch. Once Energex installed Smart Meter the Inverter was running hotter (I think) and 7.2 was maximum we saw. How can you check or know if Fronius is derating or not?

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                                                          Mark C said :administrator Report 5 years ago

                                                          Hi Alex, yes you could do the fit part using the relay in the inverter that we used to use for hot water control. Doing the second part seems a bit like you would need to reinvent the wheel though!

                                                            Alex said :Guest Report 5 years ago

                                                            Hi Mark. Great Blog! I have a 5kW Fronius Primo and am looking to expand by getting another Primo and a Fronius Smart Meter to do export limiting. I was wondering if it would also be possible to add a battery via the inverter input terminals? During the day if the excess power was more than 2kW then a relay would turn on and an EV battery pack would be charged up using an AC level 1 charger. During the night a contactor would switch the solar panel terminals with the battery terminals allowing the battery to feed the inverter, so long as the battery had a cut off voltage, the export limiting could be changed to zero kW and the inverter output could be limited to handle the battery current draw. Could this work? Thanks.

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                                                            Mark C said :administrator Report 5 years ago

                                                            Hi Geoff, Assuming it does not affect your feed-in tariff, I would go with a Fronius 5kW AUS inverter.

                                                              Geoff said :Guest Report 5 years ago

                                                              Love the review Mark, I am told I need to replace an 8 year old SMA Sunnyboy due to a mother board failure? I have 22 panels each being 225kw so a total 4.9KW in panels, The SB was a 4 KW inverter, and didn’t seem to last. Is a Fronius Primo 4.0 the best choice as a replacement or should we go larger with the Fronius Primo 5.0 AUS. Thanks in advance

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                                                              Mark Cavanagh said :administrator Report 5 years ago

                                                              Hi Sean, No there would be no benefit in getting the SC if you don't need to parallel. Standard fronius inverters have wifi and lan integrated, but you can buy a "light" version, without the datamanager card. You would only do this if you have multiple inverters on one site. In this case, the inverters can share one datamanager cared.

                                                                Mark Cavanagh said :administrator Report 5 years ago

                                                                Hi Gibbon, that's correct.

                                                                  Mark C said :administrator Report 5 years ago

                                                                  Hi Viki, the Goodwe would work as well because each panel would be about 30 volts. But you can't compare the two inverters. Fronius is better by a mile.

                                                                    Mark C said :administrator Report 5 years ago

                                                                    Hi Sue, We don't install in Melbourne but I'd recommend Gippsland Solar. Fronius and Sunpower is the best pick for sure, and Gippsland partner with both products.

                                                                      Sue said :Guest Report 5 years ago

                                                                      Hi Mark, thanks so much for your illuminating blog! I'm investigating solar in Melbourne, with single phase and have been recommended a 5K string inverter (including Delta or Fronius) with 16 -17 panels (Sunpower or LG) and also a Solaredge system with a 4K inverter and 16 LG panels. On the basis of your review, I think it best to avoid Solaredge. But which is best? I have unshaded west and east orientations, and a small north face with an antenna. Do you do any installations in Melbourne?

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                                                                      Sean said :Guest Report 5 years ago

                                                                      Hi Mark, A couple of questions about the Primo 5.0-1 and SC version: 1) If I am installing 2 strings with 2 MPPTs (8 panels East and 14 panels West, 6.6kW), would there be any benefit of spending extra for the SC version to get 18A stack capability? Will the standard INT version with 12A stacks be sufficient? Or would the added stack capacity translate to higher reliability? 2) Do all Primo 5.0-1 supplied by Fronius Australia to solar installers have wifi and LAN capability integrated? Or do I need to spend extra $ on the DataManager V2 card? Cheers! Sean

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                                                                      Vicki said :Guest Report 5 years ago

                                                                      Hi Mark - I've just read your great review on Fronius inverters. The Primo was recommended to me because of it's low startup voltage (80W) which might solve the problem of only having 5 panels on a string. I have limited roof space on a NE-facing roof and can only get 5 panels on it (and 7-8 on the NW). The Goodwe inverter I'm being pressured to buy has a startup voltage of 120V - which I understand may or may not work with 5 panels. The salesman says no problem. Could you please give me your thoughts on this, and possibly also on the panels you would use with the Fronius to get around this issue? Many thanks!

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                                                                      Gibon said :Guest Report 5 years ago

                                                                      Hi, Thank you for reply. Does that mean that i will not be able to monitor (produced, consumed, supplied to the grid power) the inverter anyhow, even if connect LAN cable?

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                                                                      Mark C said :administrator Report 5 years ago

                                                                      Hi Gibbon, No the light version does not have the data manager card. The light was made for using multiple inverters on one premise. Interlink the inverters and it shares the 1 datamanager card.

                                                                        Mark C said :administrator Report 5 years ago

                                                                        Hi MZ, yes you can connect multiple inverters together for compliance and for monitoring.

                                                                          Mark C said :administrator Report 5 years ago

                                                                          Hi, I'd suggest you go Fronius every day of the week. But also look up the history of the company. How long have they been in business? ABN lookup, reviews, are they electrical contractors and CEC Approved Retailers etc.

                                                                            Vivek said :Guest Report 5 years ago

                                                                            Hi Mark, I have been quoted 6.6kw system with Seraphim Eclipse panels and Solaredge inverter by a company in Melbourne but i am confused as another company with $100 difference quoted for the same size Suntech panels with Fronius Primo 5 inverter. My main requirement was that i wanted a battery ready system if i was to install a battery in future. And also a reliable system like everyone else. Thanks

                                                                            • 3750
                                                                            Gibon said :Guest Report 5 years ago

                                                                            Hi Mark, can you please let me know if it is only difference between LIGHT version is that it has no WiFi connection or there is some other parameters difference from full vers? If i connect FRONIUS LIGHT with internet cable to internet will it be the same features as full version with WiFi?

                                                                            • 4007
                                                                            MZ said :Guest Report 5 years ago

                                                                            Is it possible to connect multiple fronius inverters together? Means for 10kW can I connect two 5kW inverters? It doesnt mention this in any spec sheet.

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                                                                            Mark C said :administrator Report 5 years ago

                                                                            Hi Scott, Energex regulations say that multiple single-phase inverters must be interconnected so that if one shuts down, the others shut down. That can't be done across brands. It would probably be most cost-effective to install 15kW symo inverter and add the existing panels (minus the optimisers) to the new inverter.

                                                                            • 4007
                                                                            Scott said :Guest Report 5 years ago

                                                                            Where an existing SolarEdge SE5000 is on one phase, can Fronius inverters x2 be connected to the other two phases for a home with three phase power? I have sufficient roof space for about 50 more panels. Given I have the SolarEdge, I would need to add two more split core current transformers high acc to the existing measuring device behind the switchboard.

                                                                            • 4306
                                                                            Mark C said :administrator Report 5 years ago

                                                                            Hi Dave. The Fronius Primo 5.0 - 1 is not a hybrid inverter (meaning it does not have a battery charger inbuilt). The saleman would have misled you if they said it was battery ready ... however, you can still connect it to an AC coupled battery like the Tesla. AC coupled batteries like Tesla has the battery charger built into the battery rather than making the charger part of the inverter. It simplifies communications, so is not a bad option for reliability.

                                                                              Dave said :Guest Report 5 years ago

                                                                              Hi Mark why do say the Hybrid is dead in the water? I have a Fronius Primo 5.0-1 Aus. I thought it was a hybrid as it is ready to connect batteries. I do not know anything about solar but I know i just got 3 months worth of power free. cost me $322 and they gave me $323 for returned power. Any info would be great. Regards Dave.

                                                                              • 4034
                                                                              Mark C said :administrator Report 6 years ago

                                                                              Hi Neil, Yes, that's electrically possible, but in Qld it's illegal. The whole purpose of having a controlled load is so the utility can reduce demand in peak periods - and setting it up your way would defeat that objective. But... I believe in other states it is allowed.

                                                                                Neil Pierce said :Guest Report 6 years ago

                                                                                Can you use the smart meter to operate a no volt contact to switch on when your solar system is feeding surplus in to the grid and then switch off when it is not? If you can, then I believe that, along with utilising a couple of contactors, an On-relay and an Off-relay is the solution to controlling solar to only power your hot water when you have excess solar power to use. So when you aren't feeding in, then drop off the contactor sourcing Peak Tariff and pull in the contactor sourcing Low Tariff. When you are feeding in at a set level, then drop off the contactor sourcing Low Tariff and pull in the contactor sourcing Peak Tariff. It could be simplified by not using timers and instead us a mechanically interlocked reversing contactor.

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                                                                                Mark C said :administrator Report 6 years ago

                                                                                Hi Ian, NO!!! The Fronius hybrid is dead in the water. Get advice off someone local (look up my 5 simple background checks) to see if it is even worth considering batteries. I'd say no if you were in QLD, and just install a simple Fronius Symo.

                                                                                  Ian cowan said :Guest Report 6 years ago

                                                                                  Hi mark I have been looking at a fronius 5kw 3 phase inverter. I was wondering whether it is better to go with the hybrid option for an extra $2000 for future battery storage.

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                                                                                  Mark C said :administrator Report 6 years ago

                                                                                  Hi Jake, I recently blogged about SolarEdge failure rates in this blog. - I don't recommend them anymore. Instead, use Tigo, explained in this blog:

                                                                                    Jake said :Guest Report 6 years ago

                                                                                    Hi mark, I'm over looking at inverters and panels. Currently looking at purchasing Qcel G4 Q peak 300w cells x 20 with a Fronius 5kw International inverter. I was happy with my choice untill I read your blog about shade and fronius not being the best choice. I believe you directed the person to the Solaredge inverter instead. My place is very shaded to the west, I think we would average 5 hrs per day. What do you think?

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                                                                                    Mark C said :administrator Report 6 years ago

                                                                                    Hi Abish, yes Fronius do a light version.

                                                                                      Mark C said :administrator Report 6 years ago

                                                                                      Hi John, No a Symo needs 3 phase to work. You may be able to use 2 Fronius primo inverters and interlock them - depending on local regulations.

                                                                                        Abish said :Guest Report 6 years ago

                                                                                        Have you got a model called Fronius primo 5kw light With no WIFI OPTION

                                                                                        • 4211
                                                                                        John R said :Guest Report 6 years ago

                                                                                        G'day Mark. I have a 2 phase supply to my house. 1 phase running light and power, the other running heating and hot water. Would a Symo connected to the 2 phases be the best way to go? Cheers, John

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                                                                                        Mark C said :administrator Report 6 years ago

                                                                                        Hi Adam, If you don't have long mains cable (a long driveway with underground cable) and you live in town, a primo 5 will be fine. If you have flickering lights and voltage issues, it's worth going for a Symo 5. It should only be a few hundred dollars more.

                                                                                          Adam said :Guest Report 6 years ago

                                                                                          Hey guys, Iv got the option between the Primo 5 and the Symo 5. Both on a 6.55kw system on Canadian panels. What do you recommend? Advice is most appreciated.

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                                                                                          Mark C said :administrator Report 6 years ago

                                                                                          Hi Peter. you can certainly hear them when the inverter is running at full power. You probably wouldn't want it installed in your office. It looks like you are local to us - come into our showroom and we can make the fan run and you can judge for yourself!

                                                                                            Mark C said :administrator Report 6 years ago

                                                                                            Hi Dennis. If it a Fronius 5.0-1 you are fine. The power factor is just a curve ball :). The 1.33 oversize is on the nominal output, ie: 5000W

                                                                                              Peter said :Guest Report 6 years ago

                                                                                              This was a good read and is pushing me towards installing a Fronius on my house. Have you had issues with the fan noise these generate? It seems to be a polarising issue - some saying it is horrid, others saying they can barely hear a thing.

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                                                                                              dennis said :Guest Report 6 years ago

                                                                                              Thanks for the review on the Fronius 5.0.1 and 5.0.1 AUS , Its a mind field out there, I just bought the 5.0.1. I am a bit confused when the Data sheet from Fronius web site says the unit is rated at 5000w , but the rating plate on the actually unit notes its 4500w @ .9 PF , can you still install 6600w of panels on this unit and claim the rebate for 6600w or is it restricted to 6110w like the AUS unit ?

                                                                                              • 2234
                                                                                              Mark C said :administrator Report 6 years ago

                                                                                              Hi Hannes, Thanks. Yeh oversizing doesn't hurt it. In Australia, we can't oversize more than 33 per cent unless we have installed a battery.

                                                                                                Hannes Fischer said :Guest Report 6 years ago

                                                                                                Hi Mark, nice post. I normally oversize up to 50% my primos, without any problem reported in the last 5 years :) Actually Fronius warrants their Primos 50% oversizing... but... to be honest I don't think you would do them much harm oversizing, even more, let's say up to 100%, since they limit the max current and power output.

                                                                                                • 17580000
                                                                                                Mark C said :administrator Report 6 years ago

                                                                                                Hi Arian, Yes. If you have gone solarEdge, you can't change your inverter to Fronius. If you want to go Fronius, you'll need to disconnect all Solaredge optimisers. It seems your installer has the right idea, assuming regulations don't restrict you from doing 10kW of the inverter and a 5kW battery Charger (in the Powerwall).

                                                                                                  Adrian G said :Guest Report 6 years ago

                                                                                                  We have a 7 kW solar system on order: 22 x LG Neon2’s, SolarEdge SE6000H inverter, SolarEdge 370 optimizer, Powerwall2. To run our home and charge an EV. We are now looking at an EV with a 65kW battery so our installer suggests adding 8 more LG Neon2’s and a Fronius Primo 3.0-1 inverter. Is this a good idea ? Why wouldn’t we drop the SolarEdge SE6000H and go with a single Fronius Primo 8.2-1 inverter ? Is there an issue with the SolarEdge optimisers not working with Fronius gear ? Appreciate your advice.

                                                                                                  • (NZ) 0144
                                                                                                  Mark C said :administrator Report 6 years ago

                                                                                                  Hi Loom. Solar panels for residential installs are normally 60 cell. they range from about 250w to 310 watt. They are about 1-meter x 1.6 meters. Sunpower and LG have panels that are small but have up to 360W output - but they are really expensive. The 335-watt panels you are using are probably 72 cell, so they are longer by the height of 1 cell. These 72 cell panels are great for commercial installs, but we find them too difficult for residential installs. So it probably depends on if you find the panels too big and heavy to handle.

                                                                                                    Mark C said :administrator Report 6 years ago

                                                                                                    Hey Steve, Thanks. I'm in a taxi on the way from Jerusalem to meet SolarEdge in Tela Viv as I type. I also met with them a few days ago. This is also going to be a fun one to blog about :) I never thought about bridging the Fronius inputs - interesting. SolarWatt will be great if they get it integrated with Fronius. I've been talking with Nino and am hoping a better interaction with Fronius will happen soon enough. Thanks for your comments Steve!

                                                                                                      amod said :Guest Report 6 years ago

                                                                                                      Hi, I am amod from loom solar India, In our country we use normally 335 watt bigger size panel of Mono Crystalline, is that correct or we should use small size. I am unable to find answer for it.

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                                                                                                      Mark C said :administrator Report 6 years ago

                                                                                                      Hi Tracy. To answer directly, I like Canadian Solar for an entry-level product but am not a fan of Trina at all. If you have shade issues, go for Solaredge, but make sure the company you choose is well versed in Solaredge and ask them for a copy of the Solaredge site design, and make sure they give you access to the individual panel monitoring. It's easy to get Solaredge wrong. (I'm actually in Israel at the moment meeting with SolarEdge). If shade is not a big issue, go Fronius. But more importantly than the product is the company who installs it. Read this blog and do your homework on the company if you haven't already.

                                                                                                        Mark C said :administrator Report 6 years ago

                                                                                                        Hi Will, yes, that's right. But that's probably not the biggest concern. The bigger advantage of DC coupling being able to utilise more of the solar. For example, put 8kW of panels on a 5kW inverter that is DC coupled to a battery. At lunchtime, the battery could charge at 5kW while sending 3kW through the inverter, so you don't clip the production. With AC coupled you would clipping the production to 5kW.

                                                                                                          Steve said :Guest Report 6 years ago

                                                                                                          Hi Mark, Nice blog on Fronius, must have been a great trip to see where they're made and get a first hand view. Being an Electrical Contractor myself it's great to see other sparkies share my point of view in products when it comes to reliability and longevity in the solar industry. With the Primo 5 INT (and all dual input snapinverters for that matter) it is possible to simply parallel the 2 inputs at the inverter terminals by simply bridging DC+1 and DC+2 together to give max of 24A for Primo 3 - 5, or 36A for 5 AUS - 8.2. Just have to make sure you turn off MPPT tracker 2 at set up (it's actually in the installation manual). With regard to the batteries have a look at Solarwatt Matrix, a great German made DC coupled modular battery system which connects between the panels and the inverter. There are min voltages to be wary of to make sure the batteries charge, and max input current of 20A, but apart from that can be retro fitted to virtually any PV system (no need for extra inverters). Your looking at better round trip efficiency too, 92% compared to 89% for the Powerwall 2. Fronius are, or were, looking at making their smart meter compatible with the Matrix BMS, talking to Rod at the last installers night in Perth, they're having compatibility issues with sampling rates, so hopefully they can sort it out soon and will work seamlessly. Regards Steve.

                                                                                                          • 6020
                                                                                                          TraceyT said :Guest Report 6 years ago

                                                                                                          Hi Mark, I'm in Perth so we get as much sunshine as you guys in Qld. I'm looking at two quotes for installing Solar but it's hard comparing when they are using different panels and inverter's. I have read your reviews on the inverter's and I'm still confused as you've given great reviews for both the ones I've been quoted. Are you able to advise? Quote 1 is 12 x Canadian Solar panels 300W with the 3.0kw Solar Edge HD Wave inverter Quote 2 is 12 x 305w Trina Solar Honey M panels with the Fronius inverter, what are your thoughts? I see on your website you sell both inverters so I guess you rate both but what about the panels. I don't have high consumption but I would like to add a battery in a couple of years. Any thoughts?

                                                                                                          • 6154
                                                                                                          Will said :Guest Report 6 years ago

                                                                                                          Hi Mark, Using a AC coupled battery means taking AC, that has already been converted by the inverter from DC, back to DC again to charge the battery right? The overall efficiency would therefore suffer compare with DC coupled which take straight DC to charge the battery? Cheers, Will

                                                                                                          • 3305
                                                                                                          Mark C said :administrator Report 6 years ago

                                                                                                          Hi Mike. The short answer is no. If you buy a Fronius Primo now and want to get a battery later, then you would either swap your inverter for a hybrid inverter, or you would install a AC coupled battery (like Tesla PowerWall). Installing an AC coupled battery is probably more practical. Getting a Battery ready inverter now, (for a battery that you may buy in 2 years) is like buying a phone charger today for a phone you may or may not buy in 2020.

                                                                                                            Mark C said :administrator Report 6 years ago

                                                                                                            Hi Will. If there are too many panels to put in a string, you would need to parallel otherwise the voltage would get to high. (EG 16 panels north, and 6 east). Or if panels are facing different orientations (eg 8 east, 8 west and 6 north.). This blox explains it a bit better.

                                                                                                              Mike Chapman said :Guest Report 6 years ago

                                                                                                              Will Fronius make a board swop for the Primo when you want to install batteries in due course?

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                                                                                                              K. Markham. said :Guest Report 6 years ago

                                                                                                              Great review and well written, its nice to have my choice validated by someone who knows what they are talking about.

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                                                                                                              Will said :Guest Report 6 years ago

                                                                                                              Hi Mark, Why not just split the 24 panels into two strings of 12 each since the Fronius 5kw comes with 2 MPPTs? I know it is not as simple as that and there must be a good reason why someone would want to put all 24 into one MPPT. Appreciate if you can explain the details. Thanks heaps! Cheers, Will

                                                                                                              • 3305

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