Question 34Electricity & Electronics - 1st Asst/Chief

The correct answer is B) BOTH lube oil piping connections AND exciter bearings that make a connection to the alternator outboard bearing pedestal must also be insulated. The reasoning behind this is that to prevent shaft currents in an alternator, it is necessary to insulate not only the outboard bearing pedestal, but also any other conductive paths that could allow the shaft currents to flow. This includes the lube oil piping connections and the exciter bearings, as they can provide a conductive path for these harmful currents. The other options are incorrect because option A does not require insulation of the exciter bearings, option C does not require insulation of the lube oil piping connections, and option D incorrectly refers to the inboard bearing pedestal instead of the outboard pedestal.