"Doug Dotson" dougdotson@NOSPAMcablespeedNOSPAMcom wrote:
"Rosalie B." wrote in message
.. .
"Doug Dotson" dougdotson@NOSPAMcablespeedNOSPAMcom wrote:

One big house bank and a separate starting battery is best for a number
o reasons.

We have two house banks, and no starting battery. I think there are
advantages each way.

Not really.

Well you have said what you prefer, and I have said what Bob prefers.
Are you saying that Bob has no logical reason for using two house
banks? If so, that is very annoying and rude of you. If not, then
you need to work on being more tactful.

With two house banks, we can be sure that we won't use up all the
battery capacity overnight, and will have plenty of power to start the
engine up in the morning.

Same with 1 hourse and one starting battery.

Not really.

Since most of our battery use is NOT for
starting the engine, it doesn't make any sense to have the type of
battery which is basically only good for that type of use.

Yes it is since a house bank is deep cycle which is different than a
starting battery.
Using a deep cycle battery to start an engine is hard on the battery and if
for
some reason the engine is being hard to start, it may not provide enough
current
and will further damagage the bank.

It is
unused most of the time, and is basically wasted power.

Not wasted. Is your EPIRB wasted money? It is guaranteed to be
there when it is needed no matter how forgetful the operator is. The battery
is small and cheap. Mine is 1300 CCA and cost about $70.

This is irrelevant. You might just as well say that the battery
operated searchlight is wasted money because we might never need it.
Or indeed any battery operated item. Doesn't have a thing to do with
starting batteries or house batteries.

And won't the
charging system have to be different for just the one battery, than
for the house bank?

Different, but not complex. A parallelling solenoid is the simplest solution
and
something like The Eliminator or Echo Charge is the optimal solution.


We do have a large number of batteries - each bank is eight 6 volt
batteries. I think it would be hard to find enough space for that
many batteries in one place without putting them into the living
space.

Lost you here. Another point is one large unified house bank will have a
longer
total lifetime that two separate banks. I have a set of 2 8D gels that are
over
12 years old and still doing fine in almost everyday use. The boat has two
8D
AGM that have onlt barely started to loose capacity and are 6 years old.

We have had 8D wet cell batteries which came with the boat in 1998 as
the original house bank, and we replaced them with golf cart batteries
last year. When we bought her, the boat didn't have a second bank
or a starting battery IIRC.

Bob considered the cost and life span of the various types of
batteries, and decided that the life span of the new techie batteries
was not long enough to make up for the extra expense and trickier
charging problems. He figured he could replace the pack of wet cell
or golf cart 3 or 4 times for the cost of one battery pack of the more
'advanced' batteries, which would at best last twice as long. He
doesn't mind watering the batteries and checking on them occasionally.

Bob converted a car to run on electricity and ran it to work for 5
years - in the car he had 16 or 18 six volt batteries plus a 12 volt
battery for the lights and radio.

That's only because the lights and radio needed 12V and the driver motors
run at a higher voltage. Different situation.

Yes I know. But he researched the batteries for the car, and he used
golf cart batteries for that too. The whole car conversion cost less
than $5,000.00, including buying the car to convert.

Doug
s/v Callista


"Mic" wrote in message
...
Do you consider it better to have one or 2 sets of house batteries?

From the material I have read and some practical experience one seems
to be a better answer with a separate battery for the starter or as
the dock side house battery.

I think Nigel Calder goes with the one set of batteries for the house?

http://www.amplepower.com/primer/prefer/index.html

" The Preferred System

The Preferred System consists of a single house bank, and a dedicated
starter battery for all engines. A separate generator battery is
sometimes present. "

"......a two house bank system is no longer necessary. In fact, the
more battery banks in use, the less reliable the system will be, while
also increasing cost and management problems."

"Instead of a 1-2-both switch, a simple parallel switch can be used to
start the engine from the house bank if needed. "

"But, if you make the house bank from parallel batteries a cell
failure in one only knocks out that battery."

"There are other positive benefits of a single house bank versus two."
"...a gain in effective capacity results because the rate of discharge
relative to battery capacity is reduced."


grandma Rosalie