I now have configured a Multiplus 5 kVA with a grid tie inverter on the output aka "Ac Coupled" . It is running firmware 433 and ESS. The grid tie meter has an ET112 associated with it to measure its output as the inverter does not communicate modbus to GX device - all good . When I get a grid failure , the multiplus immediately goes to max allowed frequency - the frequency set to "disconnect PV inverter" . When the PV inverter comms back on line it syncs to the multiplus however with 0 power output ( as expected as Multiplus is at disconnect frequency ) . Multiplus never comes back to nominal frequency even when there is a high load on the battery. Now if disconnect the ET112 RS-485 link just prior to the grid disconnect this does not happen and the Multiplus connects to PV inverter at full power and nominal 50 Hz frequency as desired. It appears as the ET112 perhaps is still sending power information to the multiplus briefly after the grid disconnect and the multi tries to command it to shutdown ?? Will a firmware to latest fix this? I'm reluctant to change firmware as system is otherwise stable
