Export Limiting | Know Your Solar | Episode 1

[@Janmabhoomi-Kosam]

does these gen24 plus model only works with BYD battery systems? I have wired 12v lipo4 batteries i 4S config for 46v system can I connect this to Fronius? Each battery has BMS built in already.

[@Riceman-o1p]

I have a goodwe solar inverter coupled to a battery based inverter system with 14.5 kWh of energy storage. I decided not to pull a permit and the utility does not know about my solar system so I do not want to export any power. However, when I set my solar inverter to Zero export I get 50% less solar energy production per day even though my batteries are relatively empty and can take all of the solar that I could possibly give them. It seems like it's too sensitive and it curtails power output too often and it's simply is not behaving well with my battery based hybrid inverter. When I turn off the zero export function, then I get twice the daily solar energy production and all of my excess goes into my battery. So that is fine in winter but in summer I will have a problem because I have too much production.

[@robertm2170]

My Solax X1 Boost inverter still gets hot and hums even though I have reduced the export limit. My observation of the two string outputs suggests to me that it allows String 1 to operate at maximum output and that it reduces the String 2 output so that the export limit is adhered too. ie. I don’t think it operates on both strings equally so that the circuitry on String 1 works much harder. Your thoughts?

[@mcelectrical]

Yeh, this is common that it will just reduce one string when ramping down.

[@pi1325]

What is the difference between soft limit, hard limit and limit per phase?

[@pi1325]

Can i set the fronius symo gen24 export limit to 0? I dont want to send any energy tonthe grid for the moment

[@peterkrause7700]

Hi Mark. We hace a 10kW system in NSW. I believe our export limit is 3Kw. Can you explain a curious question of mine. The display on invertors are syaing they have produced 45 kWh for the day. How does that relate to 3kW? or is it simply that 3kw is 3KWhr for the day? I hope not. Great video thank you. :)

[@mcelectrical]

Hi Peter, this blog post may help clarify it further for you: www.solarquotes.com.au/blog/confusing-kw-with-kwh/

[@deanwilson7027]

So what happens to the energy that is not exported. Do the solar panels just heat up, with no where for the energy to go. And if so what impact does that have on the solar panels e.g reduce the life of the panel ?

[@mcelectrical]

Interesting question. The inverter just runs less efficiently. The inverter will change the voltage so the combination of voltage and current creates less power. (Look up I V curve.) It’s kind of like running your car in 3rd gear when driving 60k - it uses more energy to go slower. However unlike car, the inverter and panels do not work harder when this happens, so no damage to either.

[@arrowtlg2646]

@@mcelectrical Energy has to go somewhere right? Does it just heat up instead?

[@offgriddreaming5403]

Hi Do you know if the following is possible? I have a 13.2 KW grid tie system with sungrow inverter. Can i limit the export on the grid inverter and ac couple a 6kw hybrid inverter? Given that I only get 5c kw feed in anyway. Thanks

[@mcelectrical]

Hi dreamer :) In short, yes you can send wasted power to the battery. Many ways to do it. Potentially the best way for your system is to replace your Sungrow with a Tesla Powerwall 3 (assuming you are single phase)

[@SamfordFlyers]

Great video that clearly explains the benefit of using the energy above the 5kW export limit Mark (which is essentially “free power”, as there’s no lost FIT opportunity cost). I’ve got a question that’s a bit difficult to explain without an image, but are the Fronius Solar web daily use graphs accurate during periods that export limiting occurs? The current graphs show export less than 5kW during periods of low self-consumption, whereas the export should be 5kW and the self-consumption occur from the ‘free energy’ above the export limit threshold…. ?

[@mcelectrical]

Hi Jon, Hard to say without looking at the graphs, but the problem may be due to 5 minute interval monitoring.

[@SamfordFlyers]

@@mcelectrical Thanks Mark ….. I’ve now established, following an email to Fronius, that we can’t access what I described as “free power” above what I thought was the regulator imposed 5kWh export limit. Given that we’ve got a 5kWh inverter, it’s actually a “generation limit”, rather than an “export limit”….. the inverter limits the amount of power that can be used. Different story with a larger inverter though….

[@pi1325]

My fronius gen24 8kw sends equal amounts of energy to all 3 phases, even if only on L1 requires energy. And if i need 2kw on phase 1, the fronius will send 0.8 kwh on each phase, thus reducing consumption of L1 to 1,2kwh and feeding the grid through L2 and L3. How can i prevent it to send energy to other phases? I have a fronius 5ka smartmeter. The system has soft limit control of 0w, set by me. If i switch to hard limit trip, it will produce nothing. If i switch to limit per phase, it will produce arround 0,3kw divided to each phase. No matter on which phase there is demand, the other 2 phases will inject energy to the grid Something is not right.

[@mcelectrical]

This is how inverters work, a balanced load. In Australia, the metering will account for this, so you won’t be billed or paid for power in this senario.

[@pi1325]

@@mcelectrical but if u have a restriction from the energy company to not send more than 3 kwh energybinto the grid, then that is not ok. I doubt thisbisnhow it works. Also, if i need 2 kwh on L1 and i get only 0,6kwh on thatbphase, then the inverter is useless. It just means it is literally useless, because i use 0,6kwh on phase 1 and i get the rest from the grid and i pay for it....

[@g-whiz286]

If the system employs a battery bank, rather than throttling back the inverter, are there any inverters that divert the excess solar energy into battery charging?

[@mcelectrical]

Yes! Every solar/ battery system will do this. Your battery is just seen as a load, so your solar will always go to the battery instead of exporting.

[@whereswa11y]

@MC Electrical one feature you might want to highlight is the ability of the Gen24 to charge the battery from additional power sources inside the home network. IE my old panels, were charging the battery on install day before the new panels were even on the roof. So cool. However the animation , with the bubbles going in and out is broken for the case when power is coming FROM the house to the inverter, and the click on house message is also wrong. it states... "The consumption is 2.71 kW (Ohmpilot: 0 W) which is supplied entirely by the grid." which is not true. It is supplied by additional sources to the inverter.

[@mcelectrical]

Yes! Agreed, that is a pretty cool feature. It won't keep your old inverter online in a blackout, but during normal operating conditions, it can use that power to charge the battery rather than export it.

[@salvadorw.empent2778]

Hey Mark I'm new on your channel I have a question that maybe you could help me out with ,I've got a ABB TRÍO-20.0 TL-S2X-400 It has export limiting configuration and Dynamic feed in control. What I'd like to know is if this Inverter could be configured with a smart meter for zero export?

[@mcelectrical]

Welcome :) I’m sure it could. (Smart meter is the fronius branding, so it’s just called a consumption monitor)

[@robertm2170]

Can you use export limiting to reduce the amount of load on the inverter so that it does not heat up as much or reduce the humming sound?

[@mcelectrical]

Hi Robert, I would imagine that would work. Export limiting is done by running the inverter at a less efficient mpp. But it sounds a bit concerning that your inverter is running so hot or humming so loud! What brand is the inverter?

[@robertm2170]

@@mcelectrical It is a Solax X1 Boost 5Kw inverter. I had it installed two days. What I have observed is that when the solar panels are producing more than 5Kw the casing of the inverter is hot to touch and it starts to hum. With regards to a export limit the settings on the inverter are behind a 4 digit password. I understand that settings are protected by this password as most settings should not be altered by the user. So if I want this done then I would need to convince the installer.

[@Swenser]

@@robertm2170 did you get your password. Think default is 2014.

[@kleeblattsamuel]

Hi Sir, is it possible to use a export limiting inverter at Zero export and charge with it a electrical Vehicle without going through additional batteries?

[@mcelectrical]

Hi Kleenblat, yes, you’re ev becomes the load, so it should charge direct from Solar. You may want to look into “ChargeHQ” so you only use your solar to charge your ev.

[@oldcynic6964]

Question, sir: Is it possible to set up an arrangement in which some piece of gear, (say. a pool heater) gets power only when there is excess generation? ie in your example above, the solar generates 8kW, the house takes 1or 2kW, the maximum of 5kW gets exported, and whatever is unused gets routed to the pool heater. Or is that all too complicated ?

[@MrEuan616]

You could also do this with the inbuilt I/O control on the Fronius Inverter and use a relay to trigger the pool heater. Its less precise than the methods Mark has mentioned as you can only use on/off but could be useful if you are constantly exporting more than the pool heaters power.

[@1989cranston]

Ive been told that export limiting isnt a thing on a 3phase installation? or is just 5kw per phase? i got quotes for a 9.9kw solar system, there was some confusion about my house being single or 3phase and i was quoted with a single phase inverter but told about the current limiting, once i advised about the 3 phase they said no worries we will use a 3 phase inverter and you also wont be current limited for export. is this correct?

[@mcelectrical]

Hi Nick, that's correct in Qld, and in most parts of Australia I believe. Usually you can get up to 5kW export per phase.

[@1989cranston]

@@mcelectrical thanks for the reply mate. Enjoy your solar content

[@PeterMann683]

​ @mcelectrical Hi Mark, how can you tell what export limit is on your system? I have a Gen 24 Fronius Primo 5.0 inverter.

[@mcelectrical]

Depends where you live, It’s probably not export limited. Simple way if you have a smart meter is to look at your solar monitoring. Has your solar been limited on a sunny day just follow your production curve? Eg, production curve follows consumption curve in middle hours of the day on a sunny day.

[@restfulplace3273]

Nice work. More electricians need to be online

[@silcozot]

and more solar installers that have no clue about how this works

[@coconutpalm1631]

Funny how they won't impose an equivalent import limit on you though. Phase imbalance will occur on imports too as does voltage rise (though in the import direction it is "voltage drop"). So according to their reasoning (lies), pulling more than 22 amps from the grid on a single phase connection is the max unless the grid is to suffer (bullshit). The networks have been getting away with this export limiting fraud for years despite very little of their reasoning for it being grounded (no pun intended) in physics. It is also hilarious that they blame solar for high street voltages yet during the late evening peaks the voltages are just as high if not higher (this is consistently the case where I live, a metropolitan suburb).

[@mcelectrical]

Some of the rules don’t seem to make sense from an outside perspective, but the network isn’t generating or selling electricity. Their job is just to look after the stability of the grid. So while some rules might seem illogical, i would put it down to incompetence before I called it fraud.

[@jmx318]

I just got approved for 15kw of inverter at my home but only a 1.5kw export limit, what a joke 😂

[@mcelectrical]

Time to get a big battery!