Alternator Output??

[cabrillojim]

Does the Xantrex battery monitor show charge amps whether on shore battery charger or engine alternator? Should it show the sum of charger and alternator current when both are active?

The boat has 6 Gp 31 AGM, 100 AH, 12 Volt house batteries and 1 GP 31 AGM 12 volt engine battery. When running off shore power and battery charger, the Xantrex shows 50 amps (battery charge at 85%) while charging. This current level matched the level shown in the  battery charger output display.

With battery charger off, and running the engine at 2000 RPM, the Xantrex only shows the drain, not the net of charge and drain current. I expected the Xantrex to show 50 amps since the battery charge state was 85%.

Does this mean that either the regulator or alternator are not properly functioning? It is a Balmar 100 amp alternator and Max Charge regulator.

[hoppy]

It all depends on how the boat is wired up. The difference you see could be caused by the alternator cable bypassing the shunt for the Xantrex and going directly to the battery.

For diagnosing the electrics, I found a clip on multimeter totally invaluable.

[cabrillojim]

I will take a look. The wiring diagram shows the alternator positive connected to the engine battery / house battery splitter. I assume the negative is to a common ground. I assume that if that connection is downstream from the shunt, then the Xantrex will not see the current, correct? I need to look at the wiring diagrams and the actual wiring. Thx...Jim

[cabrillojim]

It was a simple fix. The alternator was not outputting any current. One wire between the alternator and the regulator was disconnected. It was the regulator on / off circuit. Reconnected it, and voila! Stuff works. The tachometer functions properly, and the Xantex show current into the batteries from alternator or battery charger.