Bruce in Bangkok wrote in
:

Well, first of all you need a "Larry Lesson" on how batteries charge
as your 110 amp alternator is just a waste of money.



No, no! Everyone knows a boat battery can be charged in 3 minutes if you
buy a big enough alternator!

Don't let logic, battery chemistry and me upset it.

On Fri, 18 Jul 2008 15:42:40 +0000, Larry wrote:

Bruce in Bangkok wrote in
:

Well, first of all you need a "Larry Lesson" on how batteries charge
as your 110 amp alternator is just a waste of money.



No, no! Everyone knows a boat battery can be charged in 3 minutes if you
buy a big enough alternator!

Don't let logic, battery chemistry and me upset it.

I had a 1988 mustang ragtop that had about ten interior lights and a
small battery. If you left a door slightly ajar, the battery would be
completely, 0 volts, dead in 45 minutes or so. A ten amp charger would
put in enough juice to start it in ten seconds. Then comes the charge
from zero at the maximum rate. Needless to say, that battery didn't
last long.

Casady

On Jul 18, 8:42*am, Larry wrote:
Bruce in Bangkok wrote :

Well, first of all you need a "Larry Lesson" on how batteries charge
as your 110 amp alternator is just a waste of money.

No, no! *Everyone knows a boat battery can be charged in 3 minutes if you
buy a big enough alternator!

Don't let logic, battery chemistry and me upset it.

In practice high output alternators make a big difference getting up
to about 80% charge. That can be very, very useful. It may be that
you have some logic and battery chemistry in your text books but I
live on my boat and go voyaging a bit. High output alternators are a
good thing.

Bummer about the Smart Car. AFIK, they aren't importing the diesel
version because in CA you can't buy diesel cars w/less than 7k miles
on them. As they say the road to hell is paved with good
intentions... But, what you really want is a diesel plug in
hybrid...

-- Tom.

On Fri, 18 Jul 2008 11:36:32 -0700 (PDT), "
wrote:

On Jul 18, 8:42*am, Larry wrote:
Bruce in Bangkok wrote :

Well, first of all you need a "Larry Lesson" on how batteries charge
as your 110 amp alternator is just a waste of money.

No, no! *Everyone knows a boat battery can be charged in 3 minutes if you
buy a big enough alternator!

Don't let logic, battery chemistry and me upset it.

In practice high output alternators make a big difference getting up
to about 80% charge. That can be very, very useful. It may be that
you have some logic and battery chemistry in your text books but I
live on my boat and go voyaging a bit. High output alternators are a
good thing.

So do Larry, Peter and myself. (Well, larry doesn't live on one, he
just voyages).

Frankly, in my experience a 110 amp alternator and a 440 A.H. battery
bank is overkill,


Bummer about the Smart Car. AFIK, they aren't importing the diesel
version because in CA you can't buy diesel cars w/less than 7k miles
on them. As they say the road to hell is paved with good
intentions... But, what you really want is a diesel plug in
hybrid...

-- Tom.

Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

On Jul 18, 4:46*pm, Bruce in Bangkok
...
In practice high output alternators make a big difference getting up
to about 80% charge. *That can be very, very useful. *It may be that
you have some logic and battery chemistry in your text books but I
live on my boat and go voyaging a bit. *High output alternators are a
good thing.

So do Larry, Peter and myself. (Well, larry doesn't live on one, he
just voyages).

Frankly, in my experience a 110 amp alternator and a 440 A.H. battery
bank is overkill,
...

Well, I've got two 110 amp alternators on a 510 AH bank and I think
that's about right. My experience is that I can bulk my batteries
quickly with my 110's. Sometimes I top them off with solar and
sometimes I work them in the 80%-50% range. Every week or so they get
a full charge and that does take a long time, but still less time than
it would with a 60 amp unit. YMMV.

-- Tom.

" wrote in news:7f8aa6de-0499-4d2c-
:

Well, I've got two 110 amp alternators on a 510 AH bank and I think
that's about right. My experience is that I can bulk my batteries
quickly with my 110's. Sometimes I top them off with solar and
sometimes I work them in the 80%-50% range. Every week or so they get
a full charge and that does take a long time, but still less time than
it would with a 60 amp unit. YMMV.

-- Tom.



Tom, how are you measuring these percentages? Are you using a hydrometer?

On Jul 18, 9:28 pm, Larry wrote:
" wrote in news:7f8aa6de-0499-4d2c-
....
Tom, how are you measuring these percentages? Are you using a hydrometer?

Zen. Well, I have an Ample Power computer but it only gives a general
feel. I've got AGM's so a hydrometer is out. Anyway, I didn't mean
for the percentages to be taken very exactly. When the batteries are
low I can throw a couple hundred amps at them for 15 minutes or so and
the absorption drops off pretty slowly. I figure until the rate is
down to 60 or so I'm saving charge time over what I'd be doing with a
normal alternator. One of the joys few joys of lead acid is that you
don't need to top them off each time you charge them. Every week or
so is fine. My feeling is it takes much less time to get charge the
bank to a 15 amp acceptance with the 110's over what it would with a
sixty...

-- Tom.

" wrote in news:1bbb3540-d522-4939-
:

When the batteries are
low I can throw a couple hundred amps at them for 15 minutes or so and
the absorption drops off pretty slowly.

200A x 12V = 2,400 watts.

No danger of overheating and warping AGM plates with only 2.4 kilowatts
forced into them at all. You should crank up the charging even further.

SARCASM OFF

If you ever get a chance to look around inside a sailboat where the battery
has exploded, don't miss this lesson in humility.

It's amazing how the middle spoons in a neat stack of "stainless" spoons is
pitted and eaten just like the ones on the ends, in a closed drawer,
outside the battery box, on the other side of the boat from the exploding
battery. Even the bellcrank on the rudder post had acid damage on it.

You gotta see it to become a believer.....

......and stop cooking lead acid batteries for life!

On Fri, 18 Jul 2008 18:18:33 -0700 (PDT), "
wrote:

On Jul 18, 4:46*pm, Bruce in Bangkok
...
In practice high output alternators make a big difference getting up
to about 80% charge. *That can be very, very useful. *It may be that
you have some logic and battery chemistry in your text books but I
live on my boat and go voyaging a bit. *High output alternators are a
good thing.

So do Larry, Peter and myself. (Well, larry doesn't live on one, he
just voyages).

Frankly, in my experience a 110 amp alternator and a 440 A.H. battery
bank is overkill,
...

Well, I've got two 110 amp alternators on a 510 AH bank and I think
that's about right. My experience is that I can bulk my batteries
quickly with my 110's. Sometimes I top them off with solar and
sometimes I work them in the 80%-50% range. Every week or so they get
a full charge and that does take a long time, but still less time than
it would with a 60 amp unit. YMMV.

-- Tom.


During your bulk charging stage what voltage are your batteries
reading and how many amps are you charging at?


Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

On Jul 19, 12:23*am, Bruce in Bangkok
wrote:
...
During your bulk charging stage what voltage are your batteries
reading and how many amps are you charging at? ...

I generally cycle the batteries on passage where I try to get away
with one hour of charging a day. We support two 12 volt, air cooled
compressors (fridge and freezer) and the auto pilot and nav lights,
RADAR, radios &c. Our solar array is usually partially shaded while
under way so we have less input there.

Keeping in mind that no two days are alike and I'm not working off of
data logs or anything: In the morning we generally see ~12 volts or a
little less on the batteries (they are always under load) and the
acceptance rate plus load is more than 200 amps. The voltage rises
slowly to 14.2~14.4 (depending on what the temp is). After about and
hour I typically shut down the engine and the acceptance plus load at
14ish is in the low teens. For the first third or so of that the
charge rate is greater than 50 amps. My take is that I'd kill
standard sized alternators pretty fast asking them to go full out for
half an hour (integessing the extra time to 50 amps) plus another 45
min of topping off and it would take more time to get to the same
charge rate. Down the list a ways you mention a cat that charges its
batteries 3 hours a day. I would find that intolerable. It seems to
me that the trick to reducing charging time is to have a good sized
alternator and know when to stop charging. It's unusual to be
offshore for more than a week without a day of calms and on those days
you can top the battery off while getting a propulsion boost form the
motor. YMMV.

-- Tom.