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Growatt 48V 6000T or 12000T do AC Coupling and Frequency Shifting with Grid tied system?

bhoth

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Hi All, I am ready to pull the trigger on a Growatt 48V 6000T or 12000T but I want to confirm it does AC Coupling and Frequency Shifting with my grid tied system.

I just had installed 22 REC 360 Watt panels with Enphase IQ7+ micro inverters and this system is grid tied. I want to make sure these Growatt 48V 6000T or 12000T will work. I also plan on ordering 16 Lishen 280ah 3.2 volt cells to run for the 48volt side.

Please let me know if the Growatt setup will work.

Thank you in advance!
 
I can't say for sure about Growatt..... but I have some questions about your set-up.

Are you wanting to use the Growatt to to keep the grid-tie system running if grid power goes down? If so, how will it be wired in? How will you ensure that there is no power feeding back to the grid when the grid is off?
 
I can't say for sure about Growatt..... but I have some questions about your set-up.

Are you wanting to use the Growatt to to keep the grid-tie system running if grid power goes down? If so, how will it be wired in? How will you ensure that there is no power feeding back to the grid when the grid is off?
I picked up the Growatt 12000T today from watts247.com (Ian is an hours drive from me so I drove down and picked one up). I will be using the Growatt 12000T to keep the grid tied system running when the power is off.

I did find out the 12000T does do AC Coupling but does not do Frequency Shifting. Ian did tell me that even though the 12000T does not do frequency shifting it still has the ability to stop charging the batteries when they become full.

Once I confirm power is off on the grid, I will for now walk outside to my main panel and kick off the main switch to the grid. Then I will kick the Growatt from standby to on. The Growatt will trick the Enphase Combiner into thinking the grid is back on and will kick back on to make power from the solar panels. When I see lights on at my neighbors house, I will turn the Growatt back to standby, wait for the Enphase combiner to kick the panels off, then turn the grid main switch back on.

The Growatt on the AC side will be connected directly to my 100 amp critical needs panel via an 80amp 240 volt breaker in my basement. The Growatt on the DC side will be connected to 16 Lishen 280ah cells to make 48 volts rated for 13.44kw.
 
Once I confirm power is off on the grid, I will for now walk outside to my main panel and kick off the main switch to the grid. Then I will kick the Growatt from standby to on. The Growatt will trick the Enphase Combiner into thinking the grid is back on and will kick back on to make power from the solar panels. When I see lights on at my neighbors house, I will turn the Growatt back to standby, wait for the Enphase combiner to kick the panels off, then turn the grid main switch back on.
Wow. Be careful!!! If you accedentally get the Growatt on at the same time the grid is on.... it could get really ugly. You should have some kind of a transfer switch that does not allow both to be in the circuit at the same time.
 
Why didn't you go with the 6000T since your solar AC is ~6,490-Watts (295-Watts AC x 22) ? Is 280Ah at 48-Volts enough storage? Why 16 instead of 15 3.2V cells since 15 is 48-Volts exactly? Will the Growatt inverter in standby allow you to run your system in grid-tied mode? Will the Growatt inverter use both solar AC and storage DC simultaneously to power your home? Sorry for all the questions, but this sounds very interesting. I have a grid-tied Enphase 20,000-Watt AC system.


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Why didn't you go with the 6000T since your solar AC is ~6,490-Watts (295-Watts AC x 22) ? Is 280Ah at 48-Volts enough storage? Why 16 instead of 15 3.2V cells since 15 is 48-Volts exactly? Will the Growatt inverter in standby allow you to run your system in grid-tied mode? Will the Growatt inverter use both solar AC and storage DC simultaneously to power your home? Sorry for all the questions, but this sounds very interesting. I have a grid-tied Enphase 20,000-Watt AC system.


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15S could potentially work depending on the specific inverter but 16S is standard so it'll be much easier to find a BMS for
 
bhoth, did you ever get your growatt to successfully AC couple with your enphase uinverters?
 
I did find out the 12000T does do AC Coupling but does not do Frequency Shifting. Ian did tell me that even though the 12000T does not do frequency shifting it still has the ability to stop charging the batteries when they become full.
Both those statements mean grid must be present.

I would not call that an AC couple-able inverter and it would be better advised (and safer) to connect PV GT inverter directly to AC grid input.
 
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Any updates on this? I have two Growatt SPF 3000TL 48v units, a 21Kw solar setup with Enphase IQ8s, and 9kWh of lithium ion batteries. I am looking for someone, or even another forum/post of anyone who has successfully gotten their enphase system to run with the growatts when disconnected from the grid.
 
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