AC Coupling of 2 5KW Deye Hybrid Inverters with own Panels and Batteries - wiring?

[Rthsw]

Hi, i have 2 more or less compatible same type, same power, same Firmware Deye 5Kw Hybrid.
My current problem is the BMS... or better the "No communicating BMS" and low Grid Voltage (Philippines).
The Inverters run until today in tandem/parallel like in the manual.
But because of the non communicating BMS both inverters have different meanings about the SoC (2 bridged No Name 150Ah 48V 15S with S.M.A.R.T BMS), after reaching +/- 80% SoC, Master Inverter 1 is still trying to charge the Batteries, and the Slave Inverter 2 stops production of Solar Energy and starts to discharge the batteries.
E.g. at 12 Noon Inverter 1 ist charging by Solar with 2.5Kw, 2nd Inverter is not using Solar, instead he uses Battery power for Output.
The both Panel sets are side by side and have the same Sun & the same power the whole Day.

I did not get the BMS to communicate via RS232 with the Inverter (maybe just a wiring problem, but i don't have PIN Layout for the BMS RS485), so i ordered 2 new BMS with CAN to replace the existing BMS and to make everything smooth... i hope.

In the meanwhile i want to run the inverters on AC Coupling in UPS Mode with 10Kw AC Peak. Possible?

Why UPS? We have Grid Voltage down to 195 Volt and i want to power the House appliances with 230 Volt 60Hz.
Why Coupling? We have sometimes Demand for 6-7 Kw Peak for two welding machines.

Config:
Every Inverter has one 150Ah/48V/7.5Kw Battery, every Inverter has 8 Panel/4Kw Peak Solar. Grid is single phase 60Hz 230 Volt (More exact: 230V Line to line, little bit like Split phase, but no Zero-potential, so more Single Phase than Split phase "Davao Light")
1st Inverter is attached to the grid, House load is attached to the LOAD Exit, CT is clamped to the Grid Supply cable.
2nd Inverter is attached with his GRID to the LOAD of the first Inverter, CT is clamped to this connection.

My Wish is to have booth inverters giving the same Power to the House, e.G. House demands for 3Kw, Inverter 1 is delivering 1.5Kw to the House LOAD, and Inverter 2 is also delivering 1.5 Kw to the House.
Is this possible? Do in need to change the wiring or the parameters?
I know i can put the 2nd inverter to the GEN Input of the first Inverter, but in this case the output is limited to 5 KW, i am right?
We have sometimes 2 Welding Inverters, Power need goes up to 6 or 7 Kw peak. That's the reason i want to parallel the inverters to have 10 Kw Peak.

It would also be ok to set the 2nd Inverter to put up to e.g. 500 Watts to the "local Grid" or "Micro Grid", and only rise on Load.

 

[timselectric]

They won't share the load equally in an AC coupling setup.
They will react to each other and the loads, instead of working with each other as a single unit.
but it will work, and provide full combined output.

 

[Rthsw]

They won't share the load equally in an AC coupling setup.
They will react to each other and the loads, instead of working with each other as a single unit.
but it will work, and provide full combined output.

OK, i could easily live with a unbalanced output. Do you also know if the described wiring correct this way?
At this moment (it is dark in the philippines now), the 1st Inverter connected to the grid is doing all the work by the grid (Battery is empty now), the 2nd inverter has his Battery at 100% SoC (53 Volt), but don't spend any energy to the Home (to the LOAD-Connector from the first Inverter).
Both are online and healthy. This means i can not use the stored Energy for the night but need to buy it from the grid.
I checked the Time of use, it is active, and Power is set to 2.500 Watt (to keep something like a Balance), and Battery is set to 46V (Current the Battery is at 53V)... but the Inverter 2 don't send to "his Grid" (which is the Load Output of the first Inverter).

 

[timselectric]

OK, i could easily live with a unbalanced output. Do you also know if the described wiring correct this way?
At this moment (it is dark in the philippines now), the 1st Inverter connected to the grid is doing all the work by the grid (Battery is empty now), the 2nd inverter has his Battery at 100% SoC (53 Volt), but don't spend any energy to the Home (to the LOAD-Connector from the first Inverter).
Both are online and healthy. This means i can not use the stored Energy for the night but need to buy it from the grid.
I checked the Time of use, it is active, and Power is set to 2.500 Watt (to keep something like a Balance), and Battery is set to 46V (Current the Battery is at 53V)... but the Inverter 2 don't send to "his Grid" (which is the Load Output of the first Inverter).

The wiring you described is fine.
My Deye is still in the box, so I haven't dug into all of the settings yet.
But you will have to force #2 to sell (export) from battery. And I believe that there are settings for this. I thought that it was in the TOU settings, but not sure.
I Wish that I could help more, but my Deye will be part of phase 3 of my project.
So, it will be a while before I get it up and running.