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  #30   IP: 69.140.244.202
Old 08-12-2013, 12:03 PM
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You can do something like this:




Quote:
Originally Posted by BadaBing View Post
I am seriously considering upgrading my alternator. I’m currently running on a rewound 35 amp atl. Over the past 7 years I have added lots of comfort add-ons that eat up power, stereo, wheel pilot, forward looking sonar, VHS radio, a 3000 watt inverter and the monster consumer, a 2 Gal 11 Amp draw (120 v) water heater. ( 3 large marine batteries #1 a single , #2 2- house)
On a very long sail, over the course of a day, switching back and forth between batteries and refreshing them with a charge I can reheat the water heater for the next nights anchorage.

However, it is a long process as the inverter draws the batteries down, ALL, in about a half hour and it takes another 2-3 to replenish them.
Solution? Speed up recharge tome with a larger alt. ( I considered a Honda or Yamaha 2000 gen. but am leaning far away from that option) After reading the above thread . Moyer's newly offered 70-120 alt seems to be about the best choice and the largest that the A4 could reasonably drive.
After reviewing the wiring for the T30 and the posted wiring schematic offered by Mr. Moyer ( THANK YOU) It looks like adding a larger atl is like having a clogged aorta, pushing more blood won’t help if we have a clog.
The Alt charge wire is a 8ga. Wire and runs a loop, from the alt to the ign switch, to the amp meter, and back to the battery switch, where the wire size jumps up to 4 Ga. (?) battery terminal wire. The 8Ga. length, not counting the small circuit size in the switch and gauge is well over 20’, likely closer to 35’.

It occurs to me that I (we) are attempting to push larger and larger volume and pressure of current through a very small wire, sort of like pushing a 3” fire hose through a ½ water pipe.
The result, so I am thinking, is that the Alt. works much harder to PUSH the current and the wire restricts how much can actually be pushed through it.
Ill going to run a couple tests on my idea but I wanted to share the thought with you all.

My thinking is upgrade to a 70-120 Alt. and to shorten the run from the alt to the battery, actually down to 3-4 ‘ directly to the battery switch, use a larger gauge 6?? Possibly 4) charge wire and see if I can add on a remote type amp meter so that the charge current does not need to pass through the ignition switch and the amp meter. Sort of a double bypass surgery. I think this will improve charge rates and reduce load on the alternator.
Any thoughts?