RE: [PSUBS-MAILIST] More Batteries....power configuration?

["Alec Smyth" <Asmyth@changepoint.com>]

I'm not an expert on this, but here's my understanding. If I'm off,
somebody please correct me.

Choosing series or parallel does not change the amount of energy stored
in your batteries, so in principle there is no difference in range,
speed, or duration. However the currents carried will change
significantly, as Amps * Volts remains constant.

Therefore a series battery bank (i.e. higher voltage) lets you use
smaller conductors. That means cheaper cable, and saved weight. If going
through the hull, the conductors on a penetrator might not be able to
carry the currents you would need at low voltages. The downside of
series arrangements is of course that you have to pay more attention to
electrical insulation, as you get into ranges that are a potential
health hazard.

Rgds,

Alec



-----Original Message-----
From: steve [mailto:steve@kobol.worldonline.co.uk] 
Sent: Monday, April 28, 2003 4:22 PM
To: personal_submersibles@psubs.org
Subject: Re: [PSUBS-MAILIST] More Batteries....power configuration?

Hi All
i have a question, how do you decide how the power systems are
configured on
a sub?
I was wondering if anyone can tell me why there are different voltages
used
and what benefits / disadvantages there are.
for instance, say my sub has 10 x 12v 110AHr batteries as its main power
source, if they were all connected in parallel, i potentially have over
1000AHrs to play with.
Why would i want to connect the batteries to give a higher voltage at a
lower current capacity?  does a motor running at 48v work more
efficiently
than a motor running at 12v or is it something more technical than that?

to put it simply, if most (or all) of the on-board systems will run on
12v
is there any benefit in running thrusters at a higher voltage?

Steve Bosworth
UK

----- Original Message -----
From: "Garry Muir" <garry.muir4@virgin.net>
To: <personal_submersibles@psubs.org>
Sent: Monday, April 28, 2003 9:23 PM
Subject: [PSUBS-MAILIST] More Batteries


> Hi Folks
>
> Try this URL for battery specs and US prices has most makes including
> Optima
>
> www.batteryweb.com/manufac.cfm
>
>
> Reagrds, Garry
>