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Lew Hodgett Lew Hodgett is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 348
Default Amps, etc.

Skip Gundlach wrote:


We've already got massive batteries. The issue is properly keeping
them charged. At 750 nominal (less aging) AH, we can go for a long
time with no charge input.


A 750AH bank will require an alternator that can put out about
110A-115A at engine idle to properly recharge them.

This will require a dual belt drive such as is required to drive a
Leece-Neville machine.

If you don't need a dual belt drive with your present alternator, you
have the wrong alternator.

If you discharge this bank by 40%, you have consumed 300AH which must
be replaced with 1.25*300 = 375 AH.

To replace 375 AH you will require 375/115 = 3.3 hours of engine time.

It ain't rocket science.

Nobody said wet cell batteries were efficient, but they are mobile.

Yes I must confess.

In my misspent youth, worked on the engineering team that designed the
great-great-great-great-grandfather of the L/N 4800.

Lew