Growatt SPF 6000 AC Bypass when Grid is Available

[bt77]

Hi
I just installed a Growatt SPF 6000 ES Plus at a friend's house. The setup is 3.2 kWp solar and a 10 kWh battery from FM-Solar.
We set it up in "SBU" mode as our intention is to feed the house loads first from solar, then from battery (if solar no longer sufficient, like at night), and finally from the grid (if battery is completely discharged).
The weird thing is the system functions as intended in offgrid mode with solar and battery connected (grid breaker open). However, the moment we close the grid breaker in addition, it automatically goes to "AC bypass" mode, basically ignoring the available solar and battery. It just starts feeding the house from the grid. We tried switching to other modes like "SOL" but it's the same outcome. If the grid breaker is closed, it will just use the grid going into "AC bypass" mode, even though the battery is at 50%+ SOC and solar panels producing energy.
I saw other users experiencing similar "AC bypass" issues with other Growatt models. Any idea how to resolve this or why the inverter could be doing this?

 

[Mattb4]

Review the battery voltage (or SOC) settings for transfer to utility and back to inverter.

 

[Brett V]

What's your battery voltage? I have the setting for back to utility at 46.0 volts and the setting for back to battery set at 51.0.

 

[bt77]

What's your battery voltage? I have the setting for back to utility at 46.0 volts and the setting for back to battery set at 51.0

I can try this. But I was thinking if I select "lithium" as battery type and the inverter is connected to the BMS via CAN interface, it would all be automatic (as managed by BMS). Are you suggesting I switch to "user defined" battery instead and set the voltages manually?

 

[Brett V]

I can try this. But I was thinking if I select "lithium" as battery type and the inverter is connected to the BMS via CAN interface, it would all be automatic (as managed by BMS). Are you suggesting I switch to "user defined" battery instead and set the voltages manually?

Does your battery have communications with the inverter? I'm using a battery that does not and have it set to USE

 

[bt77]

Does your battery have communications with the inverter? I'm using a battery that does not and have it set to USE

It does. Actually in the beginning I received the 04 Fault (Communications Error) but later figured it out that I needed to use CAN interface instead of RJ485 and the fault was cleared. So I assume it communicates with the Battery BMS. But I could still give it a shot with "USE". Thanks.

 

[Brett V]

It does. Actually in the beginning I received the 04 Fault (Communications Error) but later figured it out that I needed to use CAN interface instead of RJ485 and the fault was cleared. So I assume it communicates with the Battery BMS. But I could still give it a shot with "USE". Thanks.

I'm not sure the battery type is as important for your problem as the settings for the back to utility and back to battery. I have no experience with a battery that is communicating with the inverter but believe the principle is the same except you are inputting a batter charge percentage rather than a voltage.

 

[Jeromebricolo]

Bonjour, faites une vidéo de tout votre réglage.
ça va aider.