XW Pro won’t AC couple

Most offgrid apps do not need to rush into this. Let the Grid people test it for us 

That does not make sense to me. Curtailment of AC coupled inverters is not usually an issue in an AC coupled situation when on the grid,  because the infinite load of the grid can take any output of a GT inverter. My Skybox does have a limit on the amount of kW that can be sent to the grid and that setting can be set lower. I did that as a test and the Skybox did curtail the micros and a Solaredge inverter both of which were AC coupled to the Skybox.

When I cut the breaker and put my Skybox into essentially off grid mode I observe a lot more curtailment especially when my batteries are in CV mode and the charging current is tapering. In that case there was no grid to absorb the output of my GT inverters.

My point is that I think the Schneider tech guys have it backwards in terms of when curtailment is going to be an issue. It is going to occur more often when not on the grid. At any rate it sounds like adjusting the charging parameters may be a work around. Another one would be to put some load on the system and see if they are being curtailed. 

I should have been more clear about what did not make sense. I do agree with you that AC coupling off grid is nuts. What I was referring to was Schneider's response, but maybe you have more insight. Were all the GT inverters you tested UL1741SA? I assume you were testing AC coupling for Schneider in an off grid environment? To me that is where the issues would arise since curtailment should not be an issue when on the grid for the reasons I suggested. However when the grid is down, that is when a person who invested in a hybrid inverter to leverage his GT solar investment needs AC coupling the most. I thought Schneider would see that as an important issue and to me an off grid environment would be the easiest way to simulate a grid down environment. 
I am assuming that the issue Apex is having is curtailment of the micros for unexplained reasons? We haven't heard back from Apex if changing the voltage made things better or whether adding loads reduced the curtailment. 
In the meantime the smoke has cleared in the Sonoma Valley and solar production is back to normal. The worst day was September 9th when I got less than a kiloWatt of production and ran the A/C fan half an hour on the hours to clean the air inside. It was so dark the street lights came on at 3PM, I should update one of my ealier posts with the latest iteration of my build. I got a new pack of Lithium batteries and have been running my critical loads panel in self consumption mode for two months. My hat it off to you guys who do this every day and don't have the luxury of flipping the interlock to the grid like I do when I need to reboot the inverter or rearrange some cells. 

I spent a week in the fifties camping around Dinky Creek and Shaver Lake. My daughter spent two weeks at a camp near Huntington Lake Then in the nineties I got a tour of the Big Creek system from SCE. Beautiful country, I am glad you are safe, 

 Apex said:

...... The XW was holding the micros in curtailment at 61.5 for the whole day. Tech support has never address this detail as of yet. 

When you say the XW was holding the micros in curtailment do you mean the micros were off? Did you notice any difference at different frequencies or did the XW just maintain frequency at 61.5?

The question I asked and never heard the answer to is whether the micros have UL1741SA compliance which I believe is similar to CA Rule 21? What model are the Chilcons? I did some research and Chilcon says Model CP-720 micros are Rule 21 compliant. 
I understand the connection between the XW and the micros with regard to curtailment is the issue. The question I had is whether the micros curtail by going off line and then go through a 3 to 5 minute reboot or whether they are compliant with Rule 21 and UL1741SA and can modulate down incrementally as frequency goes up and modulate up as frequency goes back down. If the micros can not modulate with frequency then no firmware upgrade on the Schneider side can fix that. In that case it would be a limitation of the micros. They will AC couple but it will be clunky as my hypothesis would suggest if the issue is on the micro side. 
That is why I asked Dave if the tests that he did were with UL1741SA or Rule 21 GT inverters. It sounds like they must have been Rule 21 because he said there were no issues.

I hope my hypothesis is not correct that the issue may be on the micro side and that you find a solution. Hopefully the XW can use frequency to adjust the Wattage output of the micros. 

Okay, what you are telling me is the micros were modulating. That dumps my hypothesis so you are on to the solution with the XW and why it was curtailing the micros that much. Thank for clarifying and satisfying my curiosity. 

Dave Angelini said:

... What happens if you turn on loads to DC?     ..........

I would try AC loads as well but perhaps that is what Dave implied. The issue is to me is, what is causing the XW to raise the frequency to curtail the micros? The AC coupling algorithm is complicated and may be different among hybrid inverters. Does your XW have a setting for the size of the battery pack? On my hybrid, when the grid is down, the battery is the only buffer so size may influence the algorithm as will  AC loads and DC voltage settings relative to DC voltage.