Larry wrote:
Stephen Trapani wrote in news:snwki.452
:

So I hook the alternator and AC charger to the common terminal of the
big battery switch, ditch the extra wire the PO had coming off of each,
and I have terminal 1 on the big battery switch go to the starter
battery and 2 terminal go to the house battery. Is that right?



There is a problem hooking it up this way. If you EVER screw up and plug
in the charger with that switch in the OFF position, the full open
circuit voltage of the battery charger, somewhere around 20-25 pulsating
VDC, will be applied to everything connected to the COMMON side of the
switch....without the battery regulating the maximum voltage of it. This
will blow every electronic gadget hooked to it on a live circuit....EVEN
IF IT IS NOT TURNED ON! Electronic gadgets use electronic switching, not
real power switches, those push button on gadgets. It will destroy them

So call me crazy (and cheap!), but could I let a dab of 5200 harden on
the switch so it can't be turned to off? Would everything be safe then?

Thanks everyone for the help!!

Stephen

Stephen Trapani wrote in news:%JRki.613$n_
:

So call me crazy (and cheap!), but could I let a dab of 5200 harden on
the switch so it can't be turned to off? Would everything be safe then?

Thanks everyone for the help!!

Stephen



No. The reason for the switch is to make the boat "safer" during periods
of disuse or storage (misuse??). You can do the same thing by
disconnecting a battery post.

Hook the house to the house battery.
Hook the starter to the starting battery.
Put this switch in between the + terminals with battery jumper wires:
http://tinyurl.com/2qbjp7
$25 plus the cables.

You can switch it on or off any ol' time you like, even with the engine
running. All it does is act like a jumper cable jumpering one battery +
terminal to the other, letting the alternator connected to the starting
battery charge both house and starting in parallel. No matter where the
switch is positioned, house stuff is always connected to the house
battery and starting stuff is always connected to the starting battery.

The reason to use heavy wire with so heavy a switch is the "jumper cable
effect", allowing you to switch it on to crank the beast from the house
batteries....unless, of course, they are dead.

The contactors I previously posted do just what this switch will
do....but will NOT let you go off for a couple of months leaving the
batteries paralleled, killing them all in the process.

You can eliminate the A-B-Both-OFF switches if you like. That also keeps
the wife from switching the house to the starting battery when the lights
start to go dim and you're not watching her....(c;



Larry
--
While in Mexico, I didn't have to press 1 for Spanish.
While in Iran, I didn't have to press 1 for Farsi, either.
It just isn't fair.

On Tue, 10 Jul 2007 02:34:01 +0000, Larry wrote:

Stephen Trapani wrote in news:snwki.452
:

So I hook the alternator and AC charger to the common terminal of the
big battery switch, ditch the extra wire the PO had coming off of each,
and I have terminal 1 on the big battery switch go to the starter
battery and 2 terminal go to the house battery. Is that right?



There is a problem hooking it up this way. If you EVER screw up and plug
in the charger with that switch in the OFF position, the full open
circuit voltage of the battery charger, somewhere around 20-25 pulsating
VDC, will be applied to everything connected to the COMMON side of the
switch....without the battery regulating the maximum voltage of it. This
will blow every electronic gadget hooked to it on a live circuit....EVEN
IF IT IS NOT TURNED ON! Electronic gadgets use electronic switching, not
real power switches, those push button on gadgets. It will destroy them

So, I don't advocate doing it. I advocate using an isolator for both.
The diode isolators are fine. Connect the alternator to one and the
charger to another...SEPARATELY... There are 3 terminals....BATTERY 1,
BATTERY 2, SOURCE (the alternator on one and the charger on the other).
This will CHARGE both batteries from whatever charging source is running,
even both, WITHOUT inadvertently parallelling the batteries because one
of the diodes will be reversed biased when one battery tries to load the
other when running on batteries.

The other way to do it is with continuous-duty 12VDC and 115VAC
contactors available from auto parts places more cheaply. These look
just like a starter relay, except they have coils made for continuous
duty (always on).


Larry,

Re these 12 VDC continuous duty contractors available from the auto
parts with the capacity to carry starting amperage. Can you elaborate
a bit as I could sure use some of these..


A whole bunch snipped.




Larry

Bruce in Bangkok
(brucepaigeatgmaildotcom)

--
Posted via a free Usenet account from http://www.teranews.com

Bruce wrote in
news
Re these 12 VDC continuous duty contractors available from the auto
parts with the capacity to carry starting amperage. Can you elaborate
a bit as I could sure use some of these..



They look just like regular starter solenoid relays except the coil is
larger, draws less amperage to pull in the plunger and have better
internal heat sinking. Starter solenoids use more current because they
are built so cheaply with lots less windings.

These solenoids may also be found in car stereo stores as they use them
for switching the beast power amps the kiddies have in their trunks.
Many are used to power those driving headlights with the big quartz
bulbs, too.

http://www.stancor.com/jsp/relays.jsp

I'm using the Type 70 Stancor continuous duty. It's rated at 80A
continuous and 400A "inrush", like a stalled starter would draw. Both
the battery contactors and electronics power contactor are all these
cheap relays, all sealed up to keep the sea air at bay....

Any little toggle switch (1A) can control large currents remotely with
these cheap contactors. They are sealed, so provide an explosion-proof
solution to switching battery bank monsters in the bilge.

They do draw power for this convenience....about what a cabin light
draws...1/2 to 1A off the batteries, unlike a big switch at no drain, so
you must disable them at storage time.

Larry
--
While in Mexico, I didn't have to press 1 for Spanish.
While in Iran, I didn't have to press 1 for Farsi, either.
It just isn't fair.

On Tue, 10 Jul 2007 12:45:44 +0700, Bruce
wrote:


The other way to do it is with continuous-duty 12VDC and 115VAC
contactors available from auto parts places more cheaply. These look
just like a starter relay, except they have coils made for continuous
duty (always on).


Larry,

Re these 12 VDC continuous duty contactors available from the auto
parts with the capacity to carry starting amperage. Can you elaborate
a bit as I could sure use some of these..
....
Bruce in Bangkok
(brucepaigeatgmaildotcom)

Here's a cheesy sketch of a 3 position switch capable of driving a
winch etc in either direction using beefy contactors such as the
Stancor 2 pole make contactors.... No current taken in the OFF
position.

http://www.flickr.com/photos/brian_w/803117449/

Here's the Stancor URL that Larry mentioned...
http://www.stancor.com/jsp/relays.jsp

Brian Whatcott Altus OK

On Tue, 10 Jul 2007 02:34:01 +0000, Larry wrote:

Stephen Trapani wrote in news:snwki.452
:

So I hook the alternator and AC charger to the common terminal of the
big battery switch, ditch the extra wire the PO had coming off of each,
and I have terminal 1 on the big battery switch go to the starter
battery and 2 terminal go to the house battery. Is that right?



There is a problem hooking it up this way. If you EVER screw up and plug
in the charger with that switch in the OFF position, the full open
circuit voltage of the battery charger, somewhere around 20-25 pulsating
VDC, will be applied to everything connected to the COMMON side of the
switch....without the battery regulating the maximum voltage of it. This
will blow every electronic gadget hooked to it on a live circuit....EVEN
IF IT IS NOT TURNED ON! Electronic gadgets use electronic switching, not
real power switches, those push button on gadgets. It will destroy them

So, I don't advocate doing it. I advocate using an isolator for both.
The diode isolators are fine. Connect the alternator to one and the
charger to another...SEPARATELY... There are 3 terminals....BATTERY 1,
BATTERY 2, SOURCE (the alternator on one and the charger on the other).
This will CHARGE both batteries from whatever charging source is running,
even both, WITHOUT inadvertently parallelling the batteries because one
of the diodes will be reversed biased when one battery tries to load the
other when running on batteries.

The other way to do it is with continuous-duty 12VDC and 115VAC
contactors available from auto parts places more cheaply. These look
just like a starter relay, except they have coils made for continuous
duty (always on).


Larry,

I thought I sent this a day, or so, ago but it never turned up on the
web so I'm re-sending it.

Re these 12 VDC continuous duty contractors available from the auto
parts with the capacity to carry starting amperage. Can you elaborate
a bit as I could sure use some of these to wire my power up/down
anchor winch.


Much bunch snipped.




Larry

Bruce in Bangkok
(brucepaigeatgmaildotcom)

--
Posted via a free Usenet account from http://www.teranews.com

Bruce wrote in
news
Re these 12 VDC continuous duty contractors available from the auto
parts with the capacity to carry starting amperage. Can you elaborate
a bit as I could sure use some of these to wire my power up/down
anchor winch.


You don't need continuous duty for anchor winch contactors. Any 12V
starter solenoid will work just fine. Last time I looked, Ford was still
using them on their cars...(c; That should make them really cheap.

The only difference between a 350A starting solenoid and a 350A
continuous-duty solenoid is how the coil is wound...and cooled. Both of
them will crank a diesel from the house batteries. The starting solenoid
will overheat after about 30-40 minutes of being "on". The continuous
duty coil is larger with better cooling, costs a little more to produce.

I'm using a 200A, continuous-duty solenoid to power the entire electronic
suite bus on Liohheart. It draws about 1/4A to power its coil, which is
left on for days at a time at sea. A red light over its power switch
lights up the cabin at night and reminds my captain to shut off the
electronics throughout Lionheart when he goes home. Only the emergency
VHF (an Icom M59) and the Icom M802 HF radio are separately wired. Push
the "electronics power knob" in and the boat shuts down, en masse. Works
great.

You won't overhead starter solenoid coils running the winches up and
down.....

Larry
--
While in Mexico, I didn't have to press 1 for Spanish.
While in Iran, I didn't have to press 1 for Farsi, either.
It just isn't fair.

On Wed, 11 Jul 2007 11:33:12 +0700, Bruce
wrote:


Re these 12 VDC continuous duty contractors available from the auto
parts with the capacity to carry starting amperage. Can you elaborate
a bit as I could sure use some of these to wire my power up/down
anchor winch.

The winch manufacturers sell special contactor packages for this
purpose.. I expect that these things are mechanically and/or
electrically interlocked so that they will not put a short across the
battery if you try to raise and lower the anchor simultaneously. Such
a situation _is_ possible if you aren't careful how you wire up
individual contactors.



--
Peter Bennett, VE7CEI
peterbb4 (at) interchange.ubc.ca
new newsgroup users info : http://vancouver-webpages.com/nnq
GPS and NMEA info: http://vancouver-webpages.com/peter
Vancouver Power Squadron: http://vancouver.powersquadron.ca