AC or DC Genset

[DJW]

We are looking at a 42' Maple Leaf with a DC Genset system. It has a Yanmar 3 cylinder diesel setup to run 2 200 amp alternators into a 10 golf cart battery bank with a 2500 watt inverter/charger to provide all the ac. The DC genset also drives a dive compressor. Our current boat has a 6kw Northeren Lights AC Genset. Our Northeren Lights genset has worked flawlessly since new in 97 and only has 300 hours on it. This is the first time I have seen a Genset set up to provide only DC and am not quite sure what to think? This boat has a one peace washer/dryer set up to run off the inverter with the genset running as well as a water maker. The main engine also has a 200 amp alternator. Any thoughts pro or con on this setup would be greatly appreciated

 

[Gord May]

inefficient ?

The DC Genset (2 x 100A @ 12VDC = 4800 Watts) has approximately 75% the capacity of your 6kW (@120VAC) Northern Lights.It’s generally easier (read cheaper) to add a DC Battery Charger to an AC Generator set-up, than it is to add an AC Inverter to a DC Gen-Set - so I’d generally prefer the “conventional” AC Generator.You don’t mention the DC Alternator output regulation, which will affect the Battery Charging algorithm the set-up provides. A good regulator is ESSENTIAL.This is NOT a blanket condemnation of DC Generators.A 10-Battery House Bank (1050 total a/h ?) is fairly large, and could probably support an even larger Inverter (say up to 3 or 3.5 kW).FWIW,Gord