Jack Klarich
Gold Member
This is for y'all running older VW engines with generators
The generators should be polarized each time there is a break in the charging system
Why do generators need to be "polarized". Auto generators need some magnetism to get started. This "residual" magnetism remains in the Field pole pieces even after the engine has stopped.
The next time the generator starts up, the residual magnetism creates a small voltage in the Armature windings. Not enough to charge the battery, but enough to allow the Field windings to draw current. As the Field current increases, the pole pieces create even more magnetism. That makes even more voltage in the Armature, and the cycle continues until the
generator is capable of producing maximum output.
What happens though to a generator which has been stored a long time or is freshly built? The residual magnetism may have decreased to the point where it can no longer get the generator started producing voltage. In the case of a new generator or one which has been mis-treated, the residual may even be of the wrong direction (North and South poles reversed).
Polarization is a simple process used to restore the Field pole residual magnetism and ensure the magnetic direction is correct.
The generators should be polarized each time there is a break in the charging system
Why do generators need to be "polarized". Auto generators need some magnetism to get started. This "residual" magnetism remains in the Field pole pieces even after the engine has stopped.
The next time the generator starts up, the residual magnetism creates a small voltage in the Armature windings. Not enough to charge the battery, but enough to allow the Field windings to draw current. As the Field current increases, the pole pieces create even more magnetism. That makes even more voltage in the Armature, and the cycle continues until the
generator is capable of producing maximum output.
What happens though to a generator which has been stored a long time or is freshly built? The residual magnetism may have decreased to the point where it can no longer get the generator started producing voltage. In the case of a new generator or one which has been mis-treated, the residual may even be of the wrong direction (North and South poles reversed).
Polarization is a simple process used to restore the Field pole residual magnetism and ensure the magnetic direction is correct.
