When an high voltage system insulation test value is suspect or recorded during an annual survey, a polarization index test is performed. What is the polarization index?

Correct Answer: Option C — The polarization index is the ratio of the insulation resistance taken at ten minutes to the insulation resistance taken at one minute.

Under USCG National Maritime Center examination standards, the accepted correct answer is: The polarization index is the ratio of the insulation resistance taken at ten minutes to the insulation resistance taken at one minute..