ARCO Marine Zeus A8000-48V 8kW Vortec Alternator w/Case Ground [4606]Zeus A8000 48V 8kW Vortec Alternator with Case Ground The ARCO Zeus A8000 48V alternator turns on at lower RPMs, runs cooler, and provides more power than other 48V alternators that are larger and heavier. This alternator continuously generates over 3kW (55 Amps)at 2,500 RPM and almost 6kW (111 Amps) at 4,000 Alternator RPM. Put in real world terms, a marine diesel engine charging at 1,200 RPM with a 3. 13: 1 pulley ratio is generating just over 5kW