"Calif Bill" wrote in message
.net...

"Chuck Gould" wrote in message
oups.com...

Calif Bill wrote:


This is a small boat, not a trawler. Either battery will start the
boat.
If the switch is on 1 then the battery connected to 1 on the switch will
start the boat and run all the electronics. Like wise on 2. Both will
connect the batteries in parallel. Both hooked up. Run the switch in
#1
for a while and then next time run it in #2. If you run it in both, and
you
have a battery failure, you may end up with no starting battery. One
bad
battery adn one dead battery. None, just disconnects both batteries for
storage. I find it much better to add another switch and install a
battery
combiner. Run the starting battery on 1 and all the electronics on 2.
Then
when you are running both batteries will charge and when not running,
only
the electronics battery will be drawn down.

Fine, as long as both batteries are "deep cycle" rated. People who
install a light duty
"starting battery" and then discharge it subtantially for house use (as
would occur with the practice you describe) will be buying new
baterries a lot more often than needed.


Lots of the small boats use the combo starting/ deep cycle battery for
both sid3s. But the main point, is they do not have a house battery setup
and a starting battery setup. The switch connects which ever battery
selected to the output of the switch and the output of the switch is wired
to the motor.


Yep! I have 2 batteries on my 20 footer, both wired to run all 12v DC
accessories and provide power to the starter. I normally switch to the 2nd
battery (deep cycle) when we are swimming off the boat for the stereo and
marine radio (weather alert), then switch back to number 1 for starting and
running.

I had 3 batteries on our 32 footer........1 house and 2 starting.

A word of caution to Charles....unless you are sure your battery switch is
ignition protected NEVER switch between batteries when the engine is
running.

" JimH" not telling you @ pffftt.com wrote in
:

A word of caution to Charles....unless you are sure your battery
switch is ignition protected NEVER switch between batteries when the
engine is running.



That's not the problem. NEVER SWITCH THE SWITCH WHEN THE ENGINE IS RUNNING
to protect the electronics, in the engine and out! The switch opens
between posts, allowing the alternator's HIGH VOLTAGE PULSES normally
absorbed by the battery charging to put over 20V pulses on your expensive
equipment!

BOTH is just like a set of jumper cables in a car. Unless the house
battery is really discharged too far, go from house battery to BOTH, not 1
so you can recharge both starting and house batteries on the way home....a
headstart for the AC charger to complete the long trickle.

By the way, unless the ride home is 10 hours long, you'll NEVER recharge
the house batteries in just 30 minutes to the boatramp. Batteries charge
slowly. Capacitors charge quickly.... Connect 2-6A automatic shutoff
charger to them when you get home or at your slip. NO Battery recharges at
30A for 30 minutes....just not possible.

Larry
--
Halloween candy left over.....
Is there a downside?