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Dry camping - battery usage - very simple question - hippieforever3 - 12-06-2008 06:24

I'm still struggling with trying to figure out if my batteries are
trashed or somehow I have an inordinately high current drain.

The facts;
4 - 12volt - 85ah marine deep cycle batteries in parallel
Batteries have been fully charged w/ external charger to 14.5+volts
current drain with almost everything off (sleep condition) = 6amps
measured with a good quality clamp ammeter

Question
How long should healthy batteries be able to maintain cranking voltage?

Regards,
GPSGary

Dry camping - battery usage - very simple question - timvasqz - 12-06-2008 07:13

some solenoids are used to maintain conductivity while energised,
some at rest . a 'continious duty solenoid' constantly uses amps to
stay open. if the noid is screwed, it is a bigger amp draw then it
was 25 years ago.

positive lead should come off first battery and negitive off the
last battery in a group.

you can use a good quality multi meter to find a positive charge in
a frame to prove a ground short. clamp the negitive battery with a
good jumper cable and poke around at the frame with a meter between
the other end of the cable and frame.
a digital thermo gun will help find amp loss also. look for heat
relitive to surrounding temps.

GregO'Connor
Tim&Greg
94ptCa
--- In WanderlodgeForum@yahoogroups.com, "hippieforever3"
wrote:
>
> I'm still struggling with trying to figure out if my batteries are
> trashed or somehow I have an inordinately high current drain.
>
> The facts;
> 4 - 12volt - 85ah marine deep cycle batteries in parallel
> Batteries have been fully charged w/ external charger to 14.5+volts
> current drain with almost everything off (sleep condition) = 6amps
> measured with a good quality clamp ammeter
>
> Question
> How long should healthy batteries be able to maintain cranking
voltage?
>
> Regards,
> GPSGary
>

Dry camping - battery usage - very simple question - Gary Smith - 12-06-2008 07:30


Gary,
You are charging the batteries at too high a voltage. 13.8-14.2 would be more appropriate. For my too cents worth (and I'm not a bird owner), you would be much better off with higher amperage batteries, and 6 volt golf cart batteries would be much better for battery life and boondocking. The 6 volt golf cart batteries are true deep cycle by design. Marine/deep cycle are a compromise between regular starting batteries and true deep cycle, and don't perform either function as well as batteries dedicatedfor that purpose.
Gary
SOB
----- Original Message -----
From: "debra@ticogps.com"
To: "WanderlodgeForum@yahoogroups.com"
Sent: Saturday, December 06, 2008 1:24 PM
Subject: [WanderlodgeForum] Dry camping - battery usage - very simple question


I'm still struggling with trying to figure out if my batteries are
trashed or somehow I have an inordinately high current drain.

The facts;
4 - 12volt - 85ah marine deep cycle batteries in parallel
Batteries have been fully charged w/ external charger to 14.5+volts
current drain with almost everything off (sleep condition) = 6amps
measured with a good quality clamp ammeter

Question
How long should healthy batteries be able to maintain cranking voltage?

Regards,
GPSGary


.


Dry camping - battery usage - very simple question - freewill2008 - 12-06-2008 12:02

For a starting point, assume the less-than-new batteries still have
75% of their original 85AH capacity. The total capacity of the 4
batteries would be (4 X 85 X .75) = 255 AH. A good rule of thumb
says that only a 50% discharge should be allowed (voltage at 50%
would be almost exactly 12), so the real available power is 255/2 ~
128 AH. Because the Cat will require about this much power to crank,
there would little reserve power for the coach interior. (Note that
with 4 fresh golf cart batteries - the original BB design, these
numbers would roughly double.)

Suppose the bus were equipped with a separate battery to crank the
Cat (a split battery system). In this case, there should be about
128/6 or 22 hours of battery available for "sleep condition" with the
existing batteries.

These are all "bench racing" numbers. Differing conditions and
interpretations could lead to a bit of change to the bottom line, but
this covers the general idea when the same batteries are used for
automotive and house systems.

Bob Griesel '84 FC31 WLII WA


--- In WanderlodgeForum@yahoogroups.com, "hippieforever3"
wrote:
>
> I'm still struggling with trying to figure out if my batteries are
> trashed or somehow I have an inordinately high current drain.
>
> The facts;
> 4 - 12volt - 85ah marine deep cycle batteries in parallel
> Batteries have been fully charged w/ external charger to 14.5+volts
> current drain with almost everything off (sleep condition) = 6amps
> measured with a good quality clamp ammeter
>
> Question
> How long should healthy batteries be able to maintain cranking
voltage?
>
> Regards,
> GPSGary
>