Having an alternator onboard is an excellent alternative to an AC diesel, AC gas, or DC generator, but your standard alternator will not suffice. This Alpha Alternator is ideally suited for use as a powerful second alternator, allowing you to rapidly finish charging and turn the engines off when moored. It produces direct current (DC) for your 12V onboard system to charge batteries (starter, service, or bow thruster) fast and complete through its 3-step charge characteristic. This alternator can be installed on any engine type. A charge regulator Alpha Pro is included and achieves maximum yield from minimum engine hours. A loss in voltage due to wiring and/or battery isolator is automatically compensated for. Using a battery isolator in conjunction with an Alpha alternator makes it possible to easily charge 2 or 3 separate battery banks simultaneously.