you really have to have modern test equipment hooked up to know what's going on in these reg/gen systems, they will all act slightly different, especially with respect to what the gauge shows and what the regulator does
the regulators have adjustments to set the 'cut in' and 'cut out' points, and the regulator controls how much of the generator output goes where, depending on the condition of the battery and the demands of the system
at that momentone of the differences between generator and alternator systems is generator output depends on speed - alternators can have higher [or max] output at low speed ...
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