--- In [email protected], "Enodreven Yahoo" <enodre...@...> wrote: > > Hi, > > I have been looking at increasing my battery storage and was wondering if > there is a way of determining what size/output my alternator should be. > > My current alternators output is I believe 50 amp and I am thinking about > increasing my battery storage to 4 X 110ah > > any advice would be appreciated > > Brian >
Dear Brian The only way to get anywhere near (and it might not be very near) is to work through a whole set of complicated calculations based on your charging regime, battery use, and various physical equations. I have published a simplified method in either set of course notes on my website (TB-Training.co.uk, but be warned I make some assumptions in the parts that few can totally agree on. Only you can do this because only you know how you use the boat and equipment. It is no use putting a larger battery bank on if the problem is that you do not run the engine long enough to put back in what you have just taken out. All that will do is to make sure it takes a little longer before you hit problems. Likewise its no use putting a larger alternator on if the problem is the battery bank is not large enough to supply your needs. If your 50 amp alternator is charging the smaller bank adequately then it should be a little more effective on the larger bank but I suspect you have problems and are trying to solve them. Please remember the alternator alone (with or without fancy extra charging gizmos) is unlikely to have time during typical boat use to get the batteries to more then about 80% charged and you will then keep loosing 20% of the available battery capacity to sulphation. This is why domestic batteries without auxiliary charging tend to only last about three years. Tony Brooks www.TB-Training.co.uk
