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How do you propose to AC couple without complying with the UL spec of the GT Inverter? Hybrid is a loose definition so you can call it "grid forming inverter" but the procees of doing it safely implies more than just providing a sine wave. It requires firmware implementation that is not trivial. AC coupling is understood and used commonly to refer to that process. The GT inverter changes its output in response to voltage and frequency variations in a specific way. Have you AC coupled to a GT inverter sucessfully?
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Question for @mudhole? What kind of inverter do you have? I thought you mentioned it had generator input. If so, is it capable of operating off grid?9 kW solar, 42kWh LFP storage. EV owner since 2012Comment
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Of course, you know that a -41 SMA inverter has a built in off-grid capability called "Secure Power Outlet". Most installers will include it as it just entails a regular 20amp recepticle wired into the inverter and a switch to activate this mode when the grid is down. Provides up to 15amps of power as long as there is enough sun on your array to support it...BSEE, R11, NABCEP, Chevy BoltEV, >3000kW installedComment
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Actually you are making an incorrect statement and may have an illegal system if you live in the USA. To be legal in the USA your solar equipment must carry a UL certification or the POCO & AHJ will not approve it. Sure if you live up in the wilderness and the nearest town is miles away you can try to get away with anything you want but it may not be safe or legal should you try to sell the place.Comment
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You are evading the question. Setting the profile on an inverter is not the same as installing an inverter that does not meet code. You are trying to suggest that there is a utility that will allow someone to install a GT inverter that backfeeds the grid and which is not UL compliant. I agree with @SunEagle that there is not such a utility in the USA.9 kW solar, 42kWh LFP storage. EV owner since 2012Comment
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Not sure what you are talking about. I am certainly not suggesting there is an utility in the US that would allow connecting non-UL GTI to their grid. The discussion is about using GTI when not connected to utility grid. My comment about some UL GTI is to indicate the possibility to potentially set different profile when using the GTI while not connected to the utility grid.Comment
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I misinterpreted your statement when you said, "Not all GTI enforce UL GTI specs so it depends on the GTI."
Have you actually AC coupled a GT inverter to to a non UL inverter off grid or are you speculating on the possibility? If so what make and model? What profile did you use?9 kW solar, 42kWh LFP storage. EV owner since 2012Comment
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that is great to know, i wondered how they would buffer for clouds etc...if i would have really thought about this i should have deduced that as well...so i would go DC, to AC (secure outlet), back to dc, then to AC...LOL I basically wanted it to keep a chest freezer frozen...I guess i could just sit next to it and cut it on and off as clouds pass, LOL...Comment
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the RSD modules that allow secure power from sma inverters are said to be no longer made. Tigo said their current RSD MIGHT WORK, but they will not test it for you. best bet is to install a carport or pergola that does not require RDS devices if you really really want this feature, otherwise you are out of luck.Comment
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SMA has been all over the map on rapid shutdown and Tigo devices. The older SMA 2014 RSD box allowed secure power to be used, but not a good device if you really wanted 3 MPPT.
SMA inverters with Secure power with TIGO devices was going to work in SMA literature right before the -41 upgrade. But now, secure power is available on -41 inverters but not with SunSpec rapid shutdown devices. They have pulled all their literature claiming secure power will work with rapid shutdown and/or optimizer devices. I know secure power works with -40 inverters work with TIGO TS4-R-O optimizers, but I don't find it very useful because, so far, my catastrophes happen when the sun isn't shining.
I have re-read this entire thread and I can't figure out whether or not the OP used rapid shutdown devices in the design.Comment
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