Amp Meter/Volt Meter Oscillation
The Question –
Battery SN 40858991 was installed 4/4/17 @ 3159.69 hrs, removed 4/16/17 @ 3162.86 hrs. Induced amp meter and Volt meter oscillation. (And panel lights) Old battery worked perfect when re installed. Why?
The Answer –
This is the old-style magnetic coil relay voltage regulator that is not fast enough to dampen the overvoltage charging that happens with an RG battery that has lower internal resistance than a flooded battery that has fewer plates per cell.
The older voltage regulator recognizes the battery is going OVER the CP limit and shuts the generator or alternator off, but the battery not being fully charged voltage starts to drop below the normal charging voltage , then the voltage regulator senses it, and the magnetic coil relay contacts close and the fast charge starts again until the battery goes over voltage again.
These events are rapid within seconds, but all electrics either go off and on, or lights flicker as the ammeter is fluctuating from charge to discharge and back and forth.
Two ways to fix the problem - replace the old voltage regulator or alternator control unit with a solid state, or go back to using an old fashioned flooded electrolyte battery.