Rectifier Regulator Schematic and Specifications

This is typical of most RR used on carburated Hondas, not sure of the FI versions.

When the demand loads for current are low and the dc bus voltage goes higher than the setpoint voltage, then the internal control triggers the SCRs (gated diodes) to dump the alternator voltage directly to ground-- thru the big green wires to the frame terminal lug.