A question for those of you who are expert in the black art of electricity -- you know who you are.
The boat I am still struggling to buy has got four battery
banks: two 24 volt service
banks (one for house, one for winches, windlass
, thrusters), and 12 volt starting batteries for each of the main engine
The boat was used as a marina queen/gin palace and is poorly equipped and will require a lot of work to make her ready for roaming the wide blue. Battery
capacity seems ok (and all the batteries are brand new) but the boat entirely lacks an invertor, and has wimpy charging
capacity -- a 35 amp Newman charging
both 24 volt banks through a splitter diode and a 10 amp charger
on the main engine
start battery. No charger
at all on the generator
start battery. And no emergency
This is fine for a marina queen where you can leave the chargers on overnight, but this will suck when you're making passage
or spending a week or so on the hook in some desolate place -- because you won't be able to charge the batteries with the generator in a reasonable amount of time. I'd like to be able to run the generator for no more than a couple of hours in the morning to make water
and charge batteries and then live in peace and quiet afterwards (the whole point of being on the hook, isn't it). So I think I need more charging capacity.
The existing 35 amp charger is a good one, so it seems a shame to throw it away. Here's my question: could I buy an additional charger of greater capacity, maybe even better an invertor/charger, ditch the diode splitter, and use it together with the old charger? I would leave the old charger dedicated solely to the service
bank, and put the new one -- maybe 60 or 70 amps -- onto the house bank. Is there any electrical
reason why this would not work? Will they interfere with each other somehow? The generator is a 6.5kVA unit which ought to be happy with the load -- maximum 70 * 24v plus 30 * 24v plus 10 * 12v = about 2.5kW maximum theoretical load from the chargers, right?
The second question concerns inverters. I have never been on a larger cruising boat without an inverter
, but the guys trying to sell me the boat say there's no good reason to have one unless I want to run an electric
teakettle or something without turning the gas on (which does not seem like reason enough to have one to me). They say audiovisual equipment
can be run with their own dedicated inverters and that I shouldn't bother. Besides computers
and A/V, I can imagine wanting to run power tools, but I guess if you're drilling or sawing away at something you won't mind the generator running. What do you guys think about the idea of going inverter-less?
Last question: is there any inherent disadvantage to combined charger/inverters, compared to separate ones?
Thanks in advance for all your words of wisdom.