AC abd DC essential busses remain powered by the emergency generator even if you manage to reset one of the main generators. The is done to protect the AC and DC essential systems. However what powers the emergency generator changes. In the emergency elec config the RAT powers the blue hydraulics, which powers the emergency generator. If you get a generator back on line and it powers everything normally, then the blue hydraulics would be powered by the blue electric pump. But the RAT would remain deployed and engaged, so if the generator tripped off again you wouldn’t have to wait 8 seconds for the system to reconfigure.