fusible link questions

[KD6JDJ at aol.com]

The fusiable link has two purposes, firstly to protect the alternator   
from over loading, and to protect sensitive electronic equipment
installed in the engine. The battery can still be over charged with out
blowing the fusilble link.

  What am I missing here???
  I assume that the alternator + is connected to the battery + using 1 wire.
  I assume that the wire is big enough to deliver ALL the current that the
produce. The windings in the stator will establish that current limit.

  When would a "systems designer" connect vonerable(spelling?) sensitive
electronic devices to any part of that ? 

  I suggest that the biggest 'practical' wire be used to connect the
alternator to the battery. If I am wrong with this 'advice' , please inform
me. But please bring some facts , or at least some actual experiences.


   Jerry