I'd think that to keep the resistance down, you'd need very thick cables to
run from the back to the solenoid. If you're going to add this much weight,
you may be better off putting the battery on top of the pax footwell and
adding some dead weight in the back - more reliable electrically and more
adjustable (both position and amount of weight)
Peter
----- Original Message -----
From: <rparigor@suffolk.lib.ny.us>
Sent: Saturday, January 21, 2006 7:16 AM
Subject: Europa-List: Battery rear for aft CG?
>
> I have heard mixed feelings on mounting battery on foot well or aft to get
> a more aft CG.
>
> I ground some numbers tonight.
>
> I used:
> ****a 62 inch CG, then calculated upset from this point
> ****used both a PC 545 (12 pounds)and PC680 (15.4 pounds)
> ****Considered the cables from the footwell to buss and motor needed on
> all three scenarios so did not penalize footwell mount
> ****used three positions on each battery: 1) top of right footwell, 2)
> right rear baggage bay, 3) right just aft of baggage bay bulkhead
> ****weight of wire used was for #4 copper clad aluminium wire, but under
> no scenario if #4 pure copper wire was used would it add more than 1 pound
> (less actual) The #4 copper clad aluminium wire is larger in diameter than
> copper #4:
> http://www.periheliondesign.com./fatwires.htm
>
> Bottom line, battery on right footwell and adding lead to forward lower
> front face of sternpost to achieve same aft CG as rear mounted battery
> adds between 7 and 9 extra pounds for a given CG!
>
> Range from 7 pounds first to 9 pounds:
> 545 / right rear baggage bay (~ 7 pounds lighter overall)
> 545 / right just aft of baggage bay bulkhead
> 680 / right rear baggage bay
> 680 / right just aft of baggage bay bulkhead ( ~ 9 pounds lighter overall)
>
> Above includes the added weight and longer run of 2 cables and its effect
> on CG.
>
> I did not include weight of lugs or battery mounting, if I did it would
> make case for aft mounted battery only look better.
>
> Comments please.
>
> Ron Parigoris
>
>
>
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