Would this violate any NEC provisions?

Also it should be noted that many(most?) utility meters will count up regardless of which way the energy is flowing (unless you have an older mechanical one). The use of any PV system without the proper utility meter, would need to be coordinated with your base load so that you aren't paying for the electricity you are sending back to the grid.
Are you sure they won't count down if energy flow is reversed? I know of a three phase install that did do that because they had the metering hooked up wrong. Was a CT metered service but after first month of billing I was still doing work at this facility and POCO guy was there doing some work at the transformer one day. He said after first billing they discovered it was going backward and he was there to fix that. I imagine it probably generated an outrageous bill and that is what got the attention to discover what happened.
 
That cord would have an MC4 connector on it to interface with the microinverter, so it would not be a suicide cord. The remaining portion of the mostly cropped out end is consistent with that.

No, MC4s are for DC. The AC plug would be some kind if multi-pin plug. Probably with pins shrouded by the plug, but still.
 
The hidden problem here is that people will put these outside and probably connect them to an outside receptacle with GFCI. GFCI receptacles are not rated for bidirectional current flow. If the GFCI trips and there is voltage on the plug side before the inverters shut down, the GFCI electronics may be damaged rendering the GFCI in operatable. This may end up shutting down the receptacle or if it just burns out the GFCI it may leave the user with an outside receptacle without GFCI protection.
 
I bought one of these inverters about 6 years back when they first came out just to see what it would do.
The one I got was just a 600W inverter it took a 24V DC input so no rapid shutdown requirement.
Every time I unplugged the inverter the cord cap instantly went dead.
I was powering it off a 200Ah 24V battery bank, then I connected it directly to some PV panels
I left it in full sun during summer and no matter what I did the most power I got out was about 250 - 300 watts,
I of course had it plugged it into a single receptacle on a individual branch circuit I had in the garage.
I showed it off to the AHJ and asked what it violated he could not come up with anything,
Next a friend whom works at the local utility and a solar contractor I work for looked at it
they all got a laugh out of it, the utility discussed it I offered to let them borrow it, none were raising the alarms.
I ended up giving it to the solar guy, I suspect its been on his roof plugged in and forgotten about all this time.
 
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The hidden problem here is that people will put these outside and probably connect them to an outside receptacle with GFCI. GFCI receptacles are not rated for bidirectional current flow. If the GFCI trips and there is voltage on the plug side before the inverters shut down, the GFCI electronics may be damaged rendering the GFCI in operatable. This may end up shutting down the receptacle or if it just burns out the GFCI it may leave the user with an outside receptacle without GFCI protection.
Also AFCI breakers. (I mentioned both in post #8.)
 
The hidden problem here is that people will put these outside and probably connect them to an outside receptacle with GFCI. GFCI receptacles are not rated for bidirectional current flow. If the GFCI trips and there is voltage on the plug side before the inverters shut down, the GFCI electronics may be damaged rendering the GFCI in operatable. This may end up shutting down the receptacle or if it just burns out the GFCI it may leave the user with an outside receptacle without GFCI protection.
I'm kind of thinking GFCI won't have much issues. They not rated for bidirectional yet at same time all they care about is equal current each conductor. Legrand GFCI's I am most familiar with - I doubt they would trip. They won't reset if there is no power on line side terminals, but if this inverter needs to see supply side voltage before it will feed anything back that really won't be much of a problem. The electronics are stout. I've seen 120 volt GFCI receptacle (Legrand) supplied by 240 volts and electronics still worked. I don't want to get into that one too much, lets just say a contractor thought he could rearrange things on one my temp services to supply certain 240 volt tools but still used the 120 volt GFCI. Not like it was powered that way for brief time, it been powered for weeks that way before I happened to find out what he did, but it still worked.
 
I'm kind of thinking GFCI won't have much issues. They not rated for bidirectional yet at same time all they care about is equal current each conductor. Legrand GFCI's I am most familiar with - I doubt they would trip.
yeah, but no. Apparently the testing has been done, and they are super not happy.

Google "Balkonkraftwerk" for the German experience with these.
There are only a few million of them: clearly a fad.

There's a guy in the USA trying to get the electrical code altered to get these legal in the USA.
NFPA does not seem interested.
So far he can only sell on Native American reservations which don't need to adopt the NEC, so many don't.
 
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yeah, but no. Apparently the testing has been done, and they are super not happy.

Google "Balkonkraftwerk" for the German experience with these.
There are only a few million of them: clearly a fad.

There's a guy in the USA trying to get the electrical code altered to get these legal in the USA.
NFPA does not seem interested.
So far he can only sell on Native American reservations which don't need to adopt the NEC, so many don't.
Probably has unbalanced current for whatever reason or even high frequency capacitive leakage issues which is also a problem with VFD's when powered through GFCI's.
 
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