A 5kva generator at unity power factor (1.0), the maximum output is 5000 watts (volts x amps x power factor / 1000), but at 0.8 power factor (Some Crommelins generators) it will be 4000 watts. Continuous running power is usually 80% of that maximum output, so 4000w (0.8 power factor) has a continuous 3200w running.