54 is a passage
making boat. The only way I could get my wife to sell the house and throw the lines was to buy a boat with modern conveniences. Hence we have a trash compactor, ice maker, dishwasher, etc. connected to the Prosine
2.0 inverter/charger. Point being that we use a lot of amps! All batteries discussed are brand new are 12volt Lifeline 8D AGM’s with 255amps each.
First things first, none of this discussion involves the 4D engine
. It is independent of the two “HOUSE” banks and the “BOW” bank (serves the windlass
and bow thruster only). The 2 8D’s on the “BOW” bank are currently not accessible for “HOUSE” usage. They get charged as an independent bank from the Prosine charger
(and maybe the engine
too, never checked).
We live aboard now and will spend the next several years cruising; the BVI during this winter and the Med for several summers after. I’m thinking about bringing my “BOW” battery
bank [510amps] to the rotary battery selector position #2 so that I have the option to combine it with my “HOUSE” bank [1020 amps: currently broken into 510 amps on #1 of the rotary dial and 510amps on #2 of the rotary dial that I leave in the “BOTH” position].
Yes, that means a total of 1530amps of house batteries. It just seems wasteful to have two huge 8D’s sitting there in the “BOW” bank being used so infrequently. That seems like over kill to me, especially when you consider that a) the engine is always running when both are in use and b) we typically run the engine for at least 30 minutes leaving or entering harbors.
I believe that Nigel Calder says that your batteries in a bank should be located near each other. Does this remain as important for giant 8D’s and adequately sized cabling? For small batteries it seems more critical.
Bank “Bow” located in the bow
Bank #1 is located in the aft cabin
(45’ aft of the Bow batteries)
Bank #2 has one 8D midships and the other 8D 20’ aft near Bank #1 (violating Nigel but seems to have been no problem so far)
1) Should I combine banks #1 and #2 into just #1 on the rotary dial AND bring “BOW” bank onto #2 of the rotary dial?
2) Any harm in using the “BOTH” position so that I have access to all 1530amps at all times while sailing or moored even though the batteries will all be at different distances from the panel and source of charging
? (except when I know I need to use the windlass
or bow thruster I will isolate so that the ensuing voltage drop of those huge loads does not knock the Raymarine
3) The bow thruster and windlass are direct wired to the “BOW” battery bank (with fuses) and will work on any setting of the rotary switch. Is there some sort of “Diode” (one-way current
flow) type device that I could put in-line with the “BOW” bank so that even while in the “BOTH” position, the bow thruster can’t draw from the 4 8D’s on the “HOUSE” and knock the Raymarine
devices offline? That would save me from every having to remember to move the selector switch off of “BOTH”.
Another big advantage of having the 1530 amp battery capacity would be that I could reduce my daily DOD (depth-of-discharge) before charging
and therefor get more life cycles from the batteries.