Technically vapors are an issue. All battery types - wet/sealed/gel/AGM - are subject to ABYC venting guidelines. There are some solutions - venting the battery enclosure or having vented caps for wet cell directed overboard somehow.
Ed On Nov 19, 2015 12:50 PM, "Robert Boyer via CnC-List" <cnc-list@cnc-list.com> wrote: > I DO use AGMs--so, vapors are not an issue. I have some space just > forward of the mast under the settee but close to the boat's centerline > that might work for battery storage--I have to check out the dimensions but > this would remove weight aft and add it close to the center of gravity. > > Bob > > Bob Boyer > S/V Rainy Days / Annapolis MD > 1983 C&C Landfall 38 - Hull #230 > email: dainyr...@icloud.com <dainyr...@icloud.com> > blog: dainyrays.blogspot.com > > "There is nothing--absolutely nothing--half so much worth doing as simply > messing about in boats." --Kenneth Grahame > > On Nov 19, 2015, at 11:54 AM, Marek Dziedzic via CnC-List < > cnc-list@cnc-list.com> wrote: > > Bob, > > as you said, the current from the house batteries should never be high, so > the wires should not be an issue. However, if you calculate your load at 30 > A and select appropriate gauge of the wire (for distance), make sure that > you install an appropriate fuse (probably not larger than 50 A) (I would do > it right on the terminal, but ABYC says, within 6 or 7 in from the > terminal) to protect that wire. Such fuse would probably allow for one > quick start of the motor (it would not allow for cranking a cranky motor). > But if you want to be able to use your house batteries for cranking, you > have to allow for at least 80 – 100 A in that cable (i.e. appropriate > gauge). Keep in mind that if you install bigger cable, your voltage loss > would be less, so you would have more energy available to you lights and > instruments (instead of heating the cabin). > > One other thought. I am not sure if putting batteries under the V-berth is > the best idea. As much as you could, you should avoid placing heavy objects > far away from the centre of gravity. In heavy weather the heavy bow would > be your enemy, not a friend. > > And finally, at least theoretically, you should not install the normal > lead-acid batteries in the cabin (where they are not vented directly > outside). If you want to install batteries below, you should use the gel or > AGM batteries. This, in turn, leads to a more complex charging system > (especially, if you are going to use AGMs). > > just a few ideas to consider > > Marek > 1994 C270, “Legato” > Ottawa, ON > > > *From:* Robert Boyer via CnC-List <cnc-list@cnc-list.com> > *Sent:* Thursday, November 19, 2015 11:24 AM > *To:* cnc-list@cnc-list.com > *Cc:* Robert Boyer <dainyr...@icloud.com> > *Subject:* Stus-List Changing weight distribution in Landfall 38 > > I am equipping my boat for 8 months per year of cruising in the Bahamas. > I have added a 19-gallon auxiliary diesel tank where my holding tank was > located (under the navigation seat) which adds weight aft. I currently > have 4 group 27 batteries which will be eventually upgraded to Group > 31's--these also are located aft. > > I have been considering moving 2 or 3 batteries from the aft cockpit > locker to some dead space under the v-berth. This would take some weight > from the aft and add it forward. (My boat currently sits about 2" high at > the bow and maybe 1 inch low at the stern with no one aboard but full fuel > tanks.) > > I could configure the batteries such that the new forward bank could be > the house bank and the starting bank (which I could probably reduce to 1 or > 2 batteries) could remain aft. My problem is sizing the cables that would > run from the forward batteries to the aft controls. As I see it, these > cables would never carry more than 30 amps (maximum charging from my solar > panels) unless I needed them for starting (in the event of a dead starting > battery). > > Does anyone have any comments or suggestions on this matter? > > Bob > > Bob Boyer > S/V Rainy Days / Annapolis MD > 1983 C&C Landfall 38 - Hull #230 > email: dainyr...@icloud.com <dainyr...@icloud.com> > blog: dainyrays.blogspot.com > > "There is nothing--absolutely nothing--half so much worth doing as simply > messing about in boats." --Kenneth Grahame > > > > _______________________________________________ > > Email address: > CnC-List@cnc-list.com > To change your list preferences, including unsubscribing -- go to the > bottom of page at: > http://cnc-list.com/mailman/listinfo/cnc-list_cnc-list.com > > > _______________________________________________ > > Email address: > CnC-List@cnc-list.com > To change your list preferences, including unsubscribing -- go to the > bottom of page at: > http://cnc-list.com/mailman/listinfo/cnc-list_cnc-list.com > > >
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