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Larry Larry is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 5,275
Default BatteryLink ACR for house & start bank

"Bob" wrote in news:1171063108.136706.100980
@v33g2000cwv.googlegroups.com:

What do you think about the BatteryLink ACR? Anybody have one? Up
side? Problems?
Baffeled BOb



Bob, drop by any Waste Marine and buy this:
http://www.westmarine.com/webapp/wcs...oducte/10001/-
1/10001/251401/0/0/battery%20switch/All_2/mode+matchallpartial/0/0

I turned it into a more manageable web address:
http://tinyurl.com/ysmmuy
click on this one to go to west marine.....

Now, connect one post with #2 battery cable to the + lead of the house
batteries. Connect the other post to the + lead of the starting
battery....

Unlike your A-Both-B battery switch, this switch is NOT dangerous to
switch with the engine running which is why I advocate adding it. It
does not cause the alternator to become disconnected from the battery
banks and zap your electronics, like the A-Both-B switch WILL, not might.

I assume your house negative and starting negative are both connected to
the engine block.

It matters not where your alternator is connected with this jumper switch
in the circuit. As long as your main battery switch is NOT set to OFF,
in a normal boat installation, it matters not whether the house is
connected to A or B or BOTH as this switch will bypass those settings
when it is closed.

Crank the engine off the starting battery, first, especially if the house
batteries are discharged. Then, switch this new switch to ON, which
simply puts the house batteries in parallel with the starting battery.
Now, with the alternator FIRMLY connected to BOTH sets of batteries, one
alternator charges them all quite nicely without blowing $100 more doing
the same, exact thing with some "gadget" you know is gonna fail.

UNLIKE the "gadget", this switch also, because it's rated for lots more
amps than you ever have available, creates a fixed-mounted "JUMPER
CABLE" to crank the engine off the house batteries + starting battery in
any worst-case-scenario you might encounter...like a dead starting
battery.

How is your house batteries banks wired to the A-Both-B switch? Are they
all just wired in series-parallel to A and the cranking battery to B like
most boats? I don't like that because if you shut the boat down and walk
away, bank 1 house batteries are STILL hooked to bank 2 house batteries
making a circuit-for-disaster if one of them has a shorted cell. Buy
another A-Both-B-Off switch while you're at Westmarine, so we can
separate these house banks AND switch out the dead bank instead of
sitting in the dark at sea. Leave this switch in BOTH until you switch
the boat off, then switch it to OFF, also to separate the house
batteries. If bank 1 goes dead for some reason, you can leave the new
switch in B and still have half your house batteries to live on until you
can fix it....instead of the hard parallel circuit always connecting the
good bank to the bad bank, discharging it all or melting them.

Don't try to get cute mounting these switches. Mount the ON-OFF switch
as close as you can to between the house bank COMMON (the new house
switch) and the starting battery by the shortest route. So, you have to
open the lazerette to switch it, big deal. Mount the new house battery
switch on the house battery box with just a new short jumper to each
bank. Westmarine has jumpers, measure how long you need when you plan
where the switch should go.

There, now you leave the house battery separator to BOTH, the old battery
switch to the house batteries (which is now a wire from here to the new
house battery separator switch), not BOTH I hope if B is the starting
battery. Close the new ON-OFF paralleling switch after you crank the
engine, but DO NOT MOVE THOSE OTHER A-BOTH-B-OFF SWITCHES AFTER THE
ENGINE IS RUNNING! All batteries are in parallel for charging. You can
open the ON-OFF switch after 30 minutes of recharging from the engine
start if you like, but it's not really necessary. The batteries take
care of who gets how much current by themselves very nicely.....fancy
regulator or not. Just remember to set the ON-OFF paralleling switch to
OFF just as soon as you shut off the engine to prevent discharging the
starting battery when you're discharging the house batteries....don't
forget. A little sign by the engine switch or throttle isn't a bad
reminder...or where you hang the engine key up for storage, either.

There, you have what's Lionheart had before my captain bought me another
alternator for the engine.

The same ON-OFF switch parallels two big golf cart batteries in series in
my stepvan to run my electronics shop....with two red AGM starting
batteries to crank the big 6.2L GM diesel that drives it. It has worked
flawlessly (even if I forget the switch occasionally) for several years.
I can even crank the beast off the golf cart monsters when the AGM
batteries fail by simply setting it to ON, the built-in jumper cables..
(c; Paralleling AGM with Golf cart wetcells has had no effect on either,
charging or, when I forget to open it, discharging....well, except they'd
all be dead, eventually if I kept loading them. My 3KW Honda EU3000i
genset powers the 40A Amel manual battery charger Cap'n Geoffrey gave me
out of Lionheart, which is hooked to the house batteries, permanently.
I'd just crank the genset, set the Amel charger to STUN and cook them all
until it would crank...an inconvenience at worst...(c;

Because the current to run the boat DOESN'T go through this extra
paralleling switch, the ON-OFF between + battery posts, it matters not if
you switch it at any time. It doesn't open the alternator circuit, at
all. It's just a jumper cable.

Everything on the boat doesn't have to include some expensive computer
nanny babysitting you. KISS is a good motto for boats.

Larry
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