1) can this system be 60 and 50 hertz? Or both? If both, can we change it in the field or is Hertz to be specified upon ordering?2) amperage?3) internal resistance in ohms?4) weight?5) shipping weight?6) water proof? Or water resistant?7) is the generator's torque load dependent? In other words, is the generator easier or hard to turn when the battery is discharged?Country:United States
