MC9 charging wire route from alternator.

[richard5933]

If all the current into and out of the house batteries is running through that shunt, it should not have taken long for the Victron meter to return to a positive (or at least zero) once the load was applied.

With ours I can push a total of about 150 amps into the house battery bank when I'm running both the 120v charger and the solar array. If the battery bank is full and there is no load, the Victron BMS will show zero amps flowing through the shunt. As I apply a load, the flow will show a negative number for a few seconds, and as long as the load is less than the 150 amps it quickly returns to zero as the solar and/or 120v charger compensate for the load.

Sounds like you were only pulling about 45 amps @ 24v, and your alternator should certainly have been able to keep up with that. From my math it would seem that your alternator is not pushing through very much.

Before you start the swap though, have you confirmed that all the wiring and connections between the alternator and the house batteries are solid and tight? It would be a shame to do the work only to discover later on that a cable had rotted from the inside out and was the cause of the poor current flow.

If you were just a touch closer to Milwaukee I'd gladly swing by and lend a hand, but I don't think I can get 'authorization' for a road trip right now.

[neoneddy]

Before you start the swap though, have you confirmed that all the wiring and connections between the alternator and the house batteries are solid and tight? It would be a shame to do the work only to discover later on that a cable had rotted from the inside out and was the cause of the poor current flow.

Am I sure?... Not entirely.  I guess the shielding  on the main 4/0 wire from the main terminal (rear passenger side) felt like it was loose, like  an unshrunk heat shrink tube over wire.  I figured I was good to there at least because I can start it no problem and the start connects there.

Just ran it again, attached the log.   I took a measurement on the field wire, it was showing 23.3v or so, while the positive was showing 24.4 .  I jumpered the wires as well with no noticeable effect, when I measured, it seemed like both were brought down to 23.3 v range, but it was hard to do it all with only 2 hands.   Sometimes I wonder if my regulator is also bad, but it checked out when I tested it.

[gumpy]

FYI, when I replaced my regulator with a solid state one, I had to run a new field wire directly from the batteries. The one that came from the RJB was not providing a proper voltage to the regulator to give me a stable output. I didn't trouble shoot it because we were in Alaska in a campground at the time. I just ran a new wire and it fixed it. That wire is still there and it's still working.

Also, it seemed like you might have multiple charging sources going on at the same time. Of course, this will confuse the regulator.