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

[Warren Greenway <opensourcesub@yahoo.com>]

There is a huge benefit to running your thrusters at
a higher voltage, as any electric car buf can attest!
Coupling efficiency in motors drops as the voltage
drops, due to the very nature of electro magnetic
fields. We aren't talking about little changes either.
I think Baldor, or some other similar manufacturer of
DC motors has a published chart to demonstrate this.

Warren.

--- steve <steve@kobol.worldonline.co.uk> wrote:
> 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
> >
> 


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