GoodWe GW8KN-ET hybrid PV inverter cold start-up from Pylontech Force H2 battery in off-grid mode

How to start the inverter using only battery power, without PV or utility grid power. 0:00 - system overview 1:10 - preparing to start 1:44 - pressing start button won't work 2:59 - battery black start 4:19 - start-up in SolarGo app 8:58 - overview of SolarGo app