Almost all boats have batteries (and some have kilowatt AC inverters to boot..) - many cruising boats carry house banks in the same range as ours...
So is the extra battery power in say a worst-case scenario like the contactor fusing, a serious concern? I can see in feshwater it would be - where a human body is a conductor - but in saltwater I'm more of an insulator...But I do have a physical cutoff I can reach from the cockpit.
Getting "bit" is always scary, but I would think a fire is a much more likely scenario for any of us.
Nigel Calder has a good article in this months Sail about the need for better fuses when dealing with high-discharge battery banks like li-ion and his favorite TPPL's.
I'm working out how to fuse my "buddy banks" per Myles's recent post - two good batteries ganging up on a shorted mate didn't sound like a recipe for happiness.
-Keith
--- In electricboats@yahoogroups.com, "Myles Twete" <matwete@...> wrote:
>
> Here's the thread: http://forum.woodenboat.com/showthread.php?t=115277 .6
> posts, 4 posters.
>
> -mt
>
>
>
> From: electricboats@yahoogroups.com [mailto:electricboats@yahoogroups.com]
> On Behalf Of Rob Johnson
> Sent: Sunday, May 30, 2010 3:57 PM
> To: electricboats@yahoogroups.com
> Subject: Re: [Electric Boats] Safety weekend
>
>
>
>
>
> On the wooden boat forum , there is a thread at the moment on safety in
> electric boats .
>
> One bloke posted of rescueing someone whose electric powered boat was
> swamped , and of copping an electric shock , and being afraid of battery
> acid spilling around.
>
> Maybe you experienced people should check in , and maybe comment.
>
> Regards Rob J.
>
>
>
> _____
>
> From: aweekdaysailor <aweekdaysailor@...>
> To: electricboats@yahoogroups.com
> Sent: Sun, 30 May, 2010 3:29:21 PM
> Subject: Re: [Electric Boats] Safety weekend
>
> It's the controller - and yes it just starts ramping down the amperage to
> cool off, but that can happen at inopportune times. I added a fan today and
> that helps - I've got a Sevcon PMAC mounted on 3/8 alum plate which in turn
> has a heatsink - all connected with that gooey thermal grease. I have a spot
> infrared sensor and it was showing about 200F on the face of the controller
> when it went into shutdown.
>
> I think the 'sensor' on my motor overheating is molten copper being thrown
> about ;) (it's the Mars brushless)
>
> And BTW...it wasn't all seriousness today - after I got some good work done
> I went out and had one of the best sails I've had in months! T-shirt &
> shorts in 15kts steady (a far cry from last weekend)
>
> -K
>
> --- In electricboats@yahoogroups.com, James Massey <jcmassey@> wrote:
> >
> > G'day Keith, All
> >
> > At 04:02 AM 30/05/2010, Keith wrote:
> > >We've lost 3 good sailors here in CA recently, so I'm spending the
> > >weekend upgrading my safety profile. <snip>
> > >I still can't sustain > 60amps without overheating, so that's a concern.
> >
> > Which component/components can't sustain 60 amps? I'd assume only the
> > controller or motor could overheat and tell you (anything else would
> > just melt down and stop)?
> >
> > Care to give a basic system description, or do you already have it in
> > hand? (If you have it in hand already, please describe your mods).
> >
> > A controller usually just goes into a shut-down mode, but motors are
> > often suffering by the time their thermal switch comes on, so if it's
> > the motor you'll probably want to do something about it soon.
> >
> > What are the options to add cooling?
> >
> > Regards
> >
> > [Technik] James
> >
>
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
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