Alright lots of info there, here's a couple things:
You won't be able to curtail because the M215 don't support it. In other words you can't slowly raise the grid freq 1hz at a time to lower the solar output by x% per hz. You can still however trip using freq shift, meaning that if the freq goes to 62.5hz they'll shut off. This is good to keep in mind while looking at inverters since curtailing is more expensive than just AC freq trip.
is 11kW the max you've ever seen or the average? You'll want to know the max it outputs for the next calculations, for example here are mine
View attachment 493768
I used the table above to calculate the charging rate for each module and cell to ensure I wasn't charging the cells at a rate higher than they were designed, to figure out if I would need cooling during charging and the size of my fuses (after figuring out the max usage of my loads). You'll also want to know the max solar output to figure out what size inverter you'll need.
Here's my parts list for the major components, I already had things like RPI, contactors, etc.
Interconnect Pannel $206.03 Amazon 6/1/19
ATS $232.68 Amazon 6/1/19
Hose to drain battery coolant $10.50 Lowes 5/22/18
BMS $2,495.00 EVTV 5/17/29
Four Module Harness for BMS $59.95 EVTV 5/17/29
Four Module Extension Harness for BMS $59.95 EVTV 5/17/29
Sigineer 12kW $2,695.00 EVTV 5/17/29
Surge Protector $119.95 EVTV 5/17/29
Surge Protector $119.95 EVTV 5/17/29
60kW Battery Pack $11,200.00 eBay 5/17/19
Pack wall mounting hardware $30.37 Lowes 6/11/19
Hydraulic Crimper $35.95 eBay 6/2/19
Module Level Fuses + Holders $82.54 OnlineComponents 6/11/19
AC Relay for ATS $11.99 Amazon 6/11/19
Bus Bars $133.13 Alro Metals 6/4/19
Insulator, 20mm Hgt, M6 Thread $33.27 Galco 6/6/19
Line Splice $70.24 Amazon 6/11/19
Wire Cutter $17.65 Amazon 6/11/19
Vise Brake $34.95 Amazon 6/11/19
Q280 Breaker (2) $60.00 Amazon 6/11/19
Q250 Breaker $9.91 Amazon 6/11/19
The main issue I see with your current setup is that you have a supply side interconnection, so islanding your home during a power outage will also disconnect your solar since that is on the meter socket itself, Would you happen to have a diagram of your circuit? I want to make sure I'm reading your post correctly, even a hand drawn one will do.
You also mentioned not being worried about UL, keep in mind that a lot of AHJs require UL listing when submitting your plans, if FL requires it I'm sure CA does as well.
I wasn't aware of there being an ability to "curtail" solar inverters using the frequency. Where is this specified and does the Sunny Boy 7000 implement this capability? I was aware of the ability to shut off any UL1741 inverter by raising or lowering the frequency above or below the limit. It seems almost abusive to use that capability to cycle the inverters every 5+ minutes plus charge time. I was a system designer and shutting down system power that frequently just seems like a rough way to limit charging.
Another thing that bothers me is both my solar inverters produce 240V and not true split phase 120V. That suggests that home 120V appliances cannot really use solar inverter power since they draw power between neutral and one 120V phase which my inverters do not support. That suggests solar power cannot be used by the home except real 240V appliances. The home would only be able to use true split phase 120V/120V to neutral and the system inverter must support split phase with flexible loading on either phase. Is my thinking correct? Tesla's PW2 inverters claim to produce flexible split phase with the load on either 120V phase.
The charging problem: I don't see a charger power supply in your list and the one you specified in an earlier post is no longer available. Solar inverters are current sources. They won't naturally provide less than 100% of the available solar power less inefficiencies. They will increase their forcing voltage to try and force current into a grid load. If they cannot Force 100% of their current onto a load, they will increase their voltage until they shut down due to overvoltage. That is not good when one is trying to limit both the maximum charge current into the batteries and stop charging one the battery is full.
So I'm not sure how your actual charging system works. An off the shelf power supply doesn't provide the constant current needed for Lithium batteries plus must be stopped at the maximum voltage and switched to a voltage source and then stopped. What capabilities do the Tesla BMS's offer? Does Tesla provide specs on that? I see
"BMS $2,495.00 EVTV 5/17/29" but I don't understand how one goes from raw AC to a proper Lithium charger with the appropriate current limit, overvoltage limiting, undervoltage cutoff, low temp cutoff etc being done by a coordination of a powersupply and the Tesla BMS, EVTV and solar inverter curtail or 60HZ 5 minute shutdown cycles. I need to look at it closer.
Doesn't it mean the maximum power output of my solar inverters at say 11KW must not EVER exceed the maximum charger current of the battery pack ( or there must be a way of throttling the inverters such as the frequency control you mentioned). But my Sunny Boy solar inverters were producing 6.6KW yesterday afternoon which was a sunny day just past the lowest sun day of the year. So wouldn't the battery pack size be set roughly at my 11KW or 11KW+4KW= 15KW per day full output since that's the most KWHRs I can charge in a day. That suggests my battery size is about the size of 60KHWHrs of a full Tesla battery pack since I can produce about 70KWHrs on a sunny summer day.
I need to measure how much power I can get away with over night to see what my lower limit is. The PG&E power shut offs this year were 3 days each and we rarely have cloudy days in August thru November. That would set my lower battery size that will "get me by". Since I can only produce about 6-7KW peak in November, that would suggest a battery size in the 30-40KWHrs size since a larger battery would have little value in November or during winter storms when the power outages are most likely. One can buy 5KW Tesla modules for about $1000 on EBAY which would require about 6 or so for $6000. Two Tesla PW2's would be 28KWHrs with 10KW continuous power output.
The Tesla PW2 design moved my 2 Sunny Boy's that are line side fed to a 200A panel on the house side of the Gateway which acts as an ATS. My thinking was to move it inside my ATS also. That would eliminate your concern. 200A panels are cheap.
The quote I have from Tesla pairs my 2 Sunny Boy systems with each of one a 200A panels and 1 Powerwall 2 each. They said this was done to avoid the 120% panel current limit rule. They left my Enphase M215 system outside the Gateway so that it isn't used for charging the PW2's. It only acts as a Grid Tie system and backfeeds Grid power while PG&E power is present only.
I have separate diagrams for my 2 systems. I have a hand done diagram of my entire system I sent to Tesla, I'll post next. I used to use a SMA RS485 monitor for my system which no longer works after 11 years. I only had one Sunny Boy failure in 11 years. So I stopped watching my system production years ago. Before my solar I had a $900+ per month PG&E bill. Now I get about $500/year check. So my system saved nearly $10k per year over 11 years it paid off during the third year. I occasionally walk out and look at the power production on the Sunny Boy panel. I checked it a few times last summer around 1PM or peak sun and say power in the 5.3-5.5KW range. Its possible it exceeds 11KW on the perfect day after I clean the panels but not by much.
If I choose to not use my Enphase based system and use less batteries such as 30KWHrs, I could use the curtail method if Sunny Boy 7000's support it. That would seem less "gross" than the shut it off for 5 minutes or more approach. I'm getting lost in details and need to get my diagram and go back and study yours.
I left and looked at your diagram:
I see the inverter charger is connected to grid only power on your service entrance panel. How would the charger get solar power for a power outage longer than one day. It appears not possible for your inverter charger to recharge off solar production each day while in backup mode. Its AC input is grid only and not connected to your house loads panel where the solar power would appear each day while the grid power was down. It would appear the Sigineer Inverter acts as both an inverter with frequency control and as your charger supply. I will look at its capability. I see Sigineer appears to have a number of products that look like possible fits to this problem. How does the"
BMS $2,495.00 EVTV 5/17/29" coordinate between the Sigineer Inverter/charger and the Tesla custom BMS's on each module?