Hello.
Please help review the following idea / schematic. The main questions - is it actually safe.
What I want to achieve is to charge EcoFlow Delta 2 when the household is connected to grid, and power the household from EcoFlow's inverter during blackouts.
I have a 2 pole mains breaker separating the apartment from grid. So when grid goes off, I turn the breaker off, then connect EcoFlow's inverter output directly to the wall socket and turn it on. When power from grid becomes available again, I turn inverter off, unplug it's output from wall socket, plug the EcoFlow's "charger" cable to wall socket, and, finally turn on the mains breaker.
I want to somehow automate this plugging and unplugging. I am not allowed to change the wiring in the apartment, because it is rented. So I cannot use Automatic Transfer Switch there.
The idea is to use 2NC-2NO 25A Contactor driven by a Controller (Isolated AC-DC converter + MCU + Relay).
When Controller is powered off, the EcoFlow charges from mains thru the normally closed contacts.
When I turn on the EcoFlow's inverter it starts powering the Controller. If Controller detects there is no mains (using Optocoupler) - it turns on the coil of contactor, and the latter one disconnects EcoFlow's charger and connects the household mains to the inverter. Of course, I need to switch mains breaker off before that.