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Baterry Charging System
Hello, Hoa - and after reading your question, my head started hurting, too! <g>
Your questions, lumped together & with the expected end goal of a workable & reliable electrical system on a hard-working cruising boat, is complex stuff. That''s why trying to pull it all out and ''paste'' into a set of plans for your boat is so daunting. OTOH, that''s what it takes to do it well...and right. (If you''re not using Calder''s book, Boatowner''s Mechanical & Electrical Manual, I''d suggest you get it; outstanding value & best single resource I''ve found. But apparently books are somewhat the problem vs. the solution).
Here''s my two cents, all of which will be overly simple & needs to be adapted to your needs:
1. Do an energy budget. List all that gear & likely use X amps needed (estimate where you con''t have hard data), and end up with an amp/hr/day requirement for your boat. It''s rare for boats with the gear you outline (golly, that''s a lot of stuff for a 3-4 month cruise! I''d reconsider the list...) to need less than 100 amp/hrs/day and 150 amp/hrs/day wouldn''t be surprising if your reefer is 12V.
2. You only want to use the ''top'' 50% of your house bank, to insure you aren''t damaging the batteries. You won''t routinely charge your house bank more than 85%, even with a smart regulator, because the charging rate reduces enough to make the charging unproductive. So...you need a bank large enough to give you the needed daily amp/hrs with 35% of its capacity for each day you don''t wish to charge. E.g. my daily energy load is about 80 amp/hrs (I have a very efficient icebox & reefer system) and I wanted to go 2 days (without wind to power my windcharger) without charging. I ended up with 4 Trojan T-105 6V batteries that were inexpensive, readily available, high quality, and wired in series/parallel to provide 440 amp/hrs. And that just about fit my equation (440 X 35% = 154 amp/hrs of useable energy while on the hook).
3. How will you supply your 110V power? Let''s assume an inverter - then you can install a Link 2000R which will manage the inverter, make it into a smart charger when plugged in, and it will also count & ''manage'' the data related to your energy system. An external regulator plugs right into it, which in turn you will need to manage your new/hi output alternator. Alternator choice is governed by several performance variables but also by the 1/2" belt that is most likely the largest your engine''s pulley can accept.
4. What I haven''t mentioned are all the little pieces that are no less important when upgrading an electrical system to its new, demanding performance level. Big, clean cables to connect up the big stuff; proper breakers and/or fuses to keep the boat from arc-welding itself when something comes lose; careful wire runs so you can keep things clear in your mind & accessible to your hands & tools. This is one clear indication of how complicated a cruising-capable electrical system upgrade can be when done well. It also helps explain why this key performance system is expensive and time-consuming to install.
Let me make a suggestion: call Jack Csenge or one of his small crew at Jack Rabbit Marine in CT (203 961-8133). Jack has sold electrical ''systems'' for many years, his approach is straightforward and understandable, and his prices are fair. Moreover, he''s there to help you over the rough spots after the gear is purchased and you are having an install problem. There may be a similarly helpful business in your local area; but they won''t be better than Jack.
Good luck! We''re returning to Trinidad by jet in a few days, afterwhich we''ll be looking for you. What''s your boat''s name?
Jack (usually aboard WHOOSH, a Pearson 424 Ketch)