Dear daniemare
Please be noted that Growatt sph series output can connect to grid like grid tie pv inverter, in addition they have battery backup function to switch to in case of network mains power outage.
But Growatt spf series are off-grid hybrid integrated (charger/inverter) that can be charged from different sources (like mains power, diesel, battery, PV; thats why called hybrid) but its output can not be connected to live grid