An EMS aka power management system goes between the breakers and the loads, it shuts down one or more appliances as to not over load the source of shore power
In a factory install the EMS is not inline after inverter output, or with inverter powered on loads
All this discussion of EMS and inverter, comes from diy inverter install, wanting to plug shore cord into inverter for easy whole house outlet use
When using OEM install with dedicated inverter outlets on pass thru, or sub panel, the EMS is before the inverter NOT after, the EMS does not operate when dry camping using inverter power
For diy whole house , when dry camping and plugging shore power cord into the inverter, turn OFF the EMS