The voltage at the armature terminal of a 6V generator can be anywhere from 1/2 volt to 7.5 volts, and still be within normal performance range. A properly polarized generator, with no wires connected to it will produce about 1/2 volt due to "residual magnetism". Once current begins to flow through the field windings the voltage will rise to about 6.5 volts before the cutout relay points close. Depending on the state of charge of the battery, correct generator output can vary from 6.5 volts to 7.5 volts, and still be within normal range. Unless both voltage and current flow are monitored, any measurement will be an educated guess. The state of charge of the battery has more influence on what the generator does than the regulator. The function of a regulator is simply to prevent overloading of the generator, or overcharging of the battery.
Jerry
