Hi,
No answer possible without knowing the size of the battery bank in amp-hours.
No one in their right mind attempts to charge past 90% while running a generator, unless they have no choice.
I would look at the Champion inverter generators rather than Honda or Yamaha.

"The chart above shows the amount of time it took a PD9155 (55-amp) converter set to three different output voltages to recharge a 125 AH (Amp Hour) battery after it was fully discharged to 10.5-volts.
mdprowash wrote:
Thanks again! I replaced the converter last year with a Progressive Dynamics 45A smart charger.. so it probably does a good job. The Genius on 6v mode does 7.25v - 3.5A
My next question.. If I bought a "blue or red" 2000 series generator.. I would need to use an adapter for the 30 amp cord to plug into one of these generators.. is that okay? If I brought my batteries down to close to 50 percent... how long would it take for one of these generators to charge them to near full capacity?