Re: Hehr 190 AMP PowerlineAlternator
Reply #7 –
I suspect that he has the wrong alternator; or at least the wrong type of voltage regulator. His previous alternator was wired to "sense" battery voltage through a wire from the isolator and bypassing the diodes (avoiding the diode voltage drop of .6vdc which would make the regulator overcharge the batteries).
"Alternator guys" have most of their experience with big trucks and cars which do not have isolators. Those are all wired up with jumpers. Even the 4-post alternators commonly come with a jumper between the field connection and the alternator output connection. This jumper should be removed and the sense wire connected to it instead.
I think I would take that alternator back and ask them for a 4-wire Hehr or Leece Neville alternator of appropriate size. Or at least make absolutely sure that this was going to work right.
Craig