To the OP:
In the pic you posted, the wire from the isolator and the wire from the battery both go to the alternator. They'll be connected together at that point anyway, so there's no difference if you run from the isolator to the alternator, or from the isolator to the battery. You'd just be connecting the isolator to the battery end of the battery-alternator wire instead of the alternator end of the same wire.
One thing to be aware of though is the wire size. You say you have a 3000w inverter - that's HUGE. 3000w / 12v = 250a !!
You need cable as thick as your thumb to support a load like that.
Last edited by dwh; 04-11-2011 at 08:07 PM.
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