[C320-list] Fuses at the 3rd Battery

[Jeff Hare]

I believe he's referring to a fuse on the charging line leading from the
charger to the battery.  That way if the charger develops a short the fuse
will blow.

As you suspected, you would really not want a fuse in line with the starter.
That cable should be bolted in place at both ends and we "expect" them to
stay bolted in place or bad things are guaranteed to happen.  :)

I mentioned earlier, if you really want to protect the battery and all the
load circuit wiring from all grossly abnormal loads, get a large 250 Amp
terminal block Fuse.  Lead a jumper from the GROUND of your battery bank
through this fuse and then connect any ground return cables the other side
of the fuse.  

This is, surprisingly, safer and much easier than trying to Fuse the
positive side of the battery (given all the things that tend to tap into the
battery positive side). Electricians tend to Look for a Ground anywhere they
can, but are strangely more particular about where they source their power
from.

-Jeff

PS:  As an interesting side note,  I was working on a boat a year or so ago
that had some really bizarre electrical system quirks.  You'd key the mic on
the VHF or Sideband and the chart plotter would reset.

What was happening was that the P/O was careful to feed properly sized +12v
lines from the battery, but just jumpered over to whatever Ground connection
was close to the area, assuming that they all lead back to the same place.
Well, they did.  Just that in one place, they all funneled through a short
8" section of 14 gauge wire.  Apparently an old power hungry piece of
equipment got removed, along with its hefty power and ground wires.  But
that ground had begun serving as the load return for a bunch of other things
added over the years.

Moral of the story:  If you have to add a wire to power something, be sure
to provide at least the same gauge of wire back to a PROPER ground bus, not
just a place that looks like ground to your volt meter.


-----Original Message-----
From: c320-list-bounces at lists.catalina320.com
[mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of
crashley at gte.net
Sent: Friday, February 15, 2008 8:58 AM
To: C320-List at Catalina320.com
Subject: Re: [C320-list] Fuses at the 3rd Battery

One comment, the starting battery shouldn't be fused so low that the starter

will blow the fuse (duh), not sure what that fuse rating needs to be but 40A

sounds a little low.

CRA
Rosebud #882

----- Original Message ----- 
From: "Jon Vez" <jonvez at comcast.net>
To: <C320-List at Catalina320.com>
Sent: Friday, February 15, 2008 5:27 AM
Subject: Re: [C320-list] Fuses at the 3rd Battery


> Bruce,
>
> All batteries should be fused...you can use the same as you did for your
> house bank...
>
> Regards,
>
> Jon
>
> -----Original Message-----
> From: c320-list-bounces at lists.catalina320.com
> [mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Bruce 
> Stanley
> Sent: Thursday, February 14, 2008 10:25 PM
> To: C320-List
> Subject: [C320-list] Fuses at the 3rd Battery
>
> C320 #1084 has 40 Amp fuses, 7" from the 2x4D batteries.........as now
> installed by Catalina.
>
> Question:
> should I have installed a FUSE, 7" from my new 80amp Starting
> Battery?????????
> Should it be 40 Amp?
>
> I followed the 3rd Starting Battery Tech notes (as on the C320IA site), 
> but
> I do not recall installing a Fuse at the Battery.
> I am a bit worried. We will be back on board, this afternoon.
>
> thanks in anticipation.
>
> Bruce Stanley #1084
> Sydney Australia
>
>