[C320-list] 4D Batteries

[Arthurpiotrowski]

Hello everyone and thank you for your input, great discussion. My question is about a separate battery kept for emergency use. I have one as well, group 27, with jumper cables stored nearby on the boat. I never had to use it, i think I would just connect it to one of my 4D battery in parallel to jump it and be able to crank the engine. Any concerns here?

-Art Piotrowski 
C320 #330

Sent from Artur’s phone

> On Apr 14, 2024, at 9:57 PM, Troy Dunn via C320-list <c320-list at lists.catalina320.com> wrote:
> 
> The short answer to your original question is simply no.  It is unrealistic
> to expect a single 4D battery to power your energy needs for more than a
> day or so at anchor.   A typical 4D is going to give you about 110 Ah of
> usable energy at 50% depth of discharge.  The typical fridge is going to
> draw about 2.5Amps per hour on average (obviously a lot of factors here).
> Add in all your other basic comforts like lights, and radio, etc and you
> will be pushing the limits of both 4D batteries and risking a call to
> TowBoat US for a jump start.  Our current setup gives us  232 Ah of usable
> house bank energy and that is just enough to get us through 2 days at
> anchor assuming we were fully charged when we left the marina and a 4-5
> hour sail with no alternator use.   (we have a seperate group 27 battery as
> a reserve for emergencies only).    Unable to answer your question about
> best 4D.   For me the best 4D is not having one on the boat.    But that’s
> a debate for a different post.
> 
> Troy Dunn
> Hull #514