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EG4 AC Coupling Fronius

OK, tried to take another look on my personal PC but could not because I ran out of power while moving your PDFs to a virus checked workflow. PDFs are scary. Imgur (you can bulk upload from PC)/pasting them as photos to the forum (works for me on Chrome on iOS) is nicer.

Need to get back to debugging some stuff for work (was looking at your PDFs during my lunchbreak on my phone which presumably is safe enough). I will check again later.
 
Why is grid sell back set to zero? Can you try setting they to 12kw?


How's the battery currently being charged?

Also, there is no sub panel correct? The 18kpv is feeding your main panel via the grid input? Do you have the CTs installed?
So Grid Sell Back set to zero as it was the default setting, and the book says it's a "limitation"

1714332974878.png

Let me change that to 12kw and see what happens.

Yes, CT's installed on the Main Sub Panel
 
Nope Nope, turned Grid Sell Back back to 0. When set to 12, it pulled from the batteries and I was sending 16kW battery + PV to the grid
 
So Grid Sell Back set to zero as it was the default setting, and the book says it's a "limitation"

View attachment 212064

Let me change that to 12kw and see what happens.

Yes, CT's installed on the Main Sub Panel
Ok fingers crossed.

I went back and saw that you have 30kw of DC coupled pv attached directly to the 18kpvs so that's how the battery is charged. So right now are the inverters supporting your main panel loads at all?
 
Crap, I didn’t check and I had to get on the road
C'est la vie 😆

Btw, is there any advantage to AC coupling in your case? You have 30kw of pv already attached. Looks like battery has no problem getting to and staying at 100%

You could connect your froniuses directly to main panel
 
They were attached to the main panel originally. If you look at those pictures, you’ll see that they were on the main grid panel 30 amp breakers when I turned them on the 18 K started having weird issues. It was like the CT were minimizing solar and was not maximizing its output.
 
As for advantage definitely I’m still grandfathered with the net metering program and the state of Louisiana and I get to sell back at equal amount so I can build up a credit overtime and already had the panels so why not
 
I have 40 kW on the on the roof and another 10 kW that I was thinking about adding, but I was pressing my limits associated with roof space
 
I was also planning to add a third battery, but I wanted to see how the performance would be with two initially before I purchased that that third one from signature solar
 
They were attached to the main panel originally. If you look at those pictures, you’ll see that they were on the main grid panel 30 amp breakers when I turned them on the 18 K started having weird issues. It was like the CT were minimizing solar and was not maximizing its output.
Hmm. Very interesting. I wonder what logic the CT could be trying to use to control things.
 
Agreed. If you notice the CT’s are in the GRID subpanel which connects to the as it was easier for me to wire them there. I don’t know if doing so will make that big a difference? Either way, I wonder why the two can’t coexist with them paralleled on the GRID subpanel?
 
So this is the stuff you want to spit nails at Signature Solar when you spend $30K. I turned on Power Backup, as a bad weather and possible tornados are headed to my home and my wife is alone, while I'm traveling for business. I get to my destination and look, and my batteries are drained to 39%. WTF? So I turned on AC Charge to make sure before the storm hits in about an hour, that if power is knocked down, she'll have power...One of the main reason I bought all this stuff. And AC Charge will not turn on. I reverse the direction of the CT and boom, I'm charging. I put them in with the arrows going back to the inverter. There's some crazy tricks to the setup in this thing that need better explanation. Maybe SS can weigh in come Monday, and pray I don't lose power.

1714358097205.png
 
So this is the stuff you want to spit nails at Signature Solar when you spend $30K. I turned on Power Backup, as a bad weather and possible tornados are headed to my home and my wife is alone, while I'm traveling for business. I get to my destination and look, and my batteries are drained to 39%. WTF? So I turned on AC Charge to make sure before the storm hits in about an hour, that if power is knocked down, she'll have power...One of the main reason I bought all this stuff. And AC Charge will not turn on. I reverse the direction of the CT and boom, I'm charging. I put them in with the arrows going back to the inverter. There's some crazy tricks to the setup in this thing that need better explanation. Maybe SS can weigh in come Monday, and pray I don't lose power.

View attachment 212135
Oh boy!

I wonder if the reversed CTs is the source of the ac cooking not working.
 
They were attached to the main panel originally. If you look at those pictures, you’ll see that they were on the main grid panel 30 amp breakers when I turned them on the 18 K started having weird issues. It was like the CT were minimizing solar and was not maximizing its output.

If Fronius GT PV is feeding current to grid, EG4 sees that and may want to adjust its current to hit a desired value.

If you were to snake the Fronius AC wires through the CT so current on Fronius wire pass in the Meter --> breaker panel direction, it's current would then then go through branch breaker, land on main panel, go back opposite direction through CT, cancelling itself. Fronius current becomes invisible to EG4, just as if it landed on grid side of CT instead of breaker panel side.
 
So this is the stuff you want to spit nails at Signature Solar when you spend $30K. I turned on Power Backup, as a bad weather and possible tornados are headed to my home and my wife is alone, while I'm traveling for business. I get to my destination and look, and my batteries are drained to 39%. WTF? So I turned on AC Charge to make sure before the storm hits in about an hour, that if power is knocked down, she'll have power...One of the main reason I bought all this stuff. And AC Charge will not turn on. I reverse the direction of the CT and boom, I'm charging. I put them in with the arrows going back to the inverter. There's some crazy tricks to the setup in this thing that need better explanation. Maybe SS can weigh in come Monday, and pray I don't lose power.

View attachment 212135
Could you DM me your name and email address? I’d like to have our support reach out to you and make sure this gets this taken care of.
 
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Yeah, something isn't right at the basic level with the EG4's. I turned off Grid AC Charge to charge the batteries from PV not charging the batteries which are at 23%. Granted it's still early but the PV power generated should be flowing to the batteries...

1714401401853.png

I wonder if I reverse the CT's again whether it would start, but I'm not. I need someone from SS who actually understands this equipment to instruct me on the commissioning.
 
Yeah, something isn't right at the basic level with the EG4's. I turned off Grid AC Charge to charge the batteries from PV not charging the batteries which are at 23%. Granted it's still early but the PV power generated should be flowing to the batteries...

View attachment 212188

I wonder if I reverse the CT's again whether it would start, but I'm not. I need someone from SS who actually understands this equipment to instruct me on the commissioning.
Looks like there is more load than pv power?

So the pv power is going directly to the loads, plus some from the grid. That's what it looks like to me
 

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