Polarizing a generator, at the regulator terminals, involves a simple procedure that ensures the generator and regulator read the same electrical polarity signal. In simple terms, the generator needs to remember how it was wired after it has been disconnected or replaced. If the regulator was recently replaced, the system still has to be polarized, since a disconnection has separated the system components. Failing to polarize can trip a generator or charging light in the system, and burn out the wiring circuit. Any repair person who has changed or disconnected the wires to the regulator, generator or alternator, needs to take a moment and polarize system.
Make sure your tractor sits in park or neutral, with the emergency brake fully applied. Remove the ignition key. Make sure your battery has a full charge.