How would you perform an insulation resistance test (Megger) on an aircraft circuit and interpret a reading?

How would you perform an insulation resistance test (Megger) on an aircraft circuit and interpret a reading?

• A. With power on and equipment connected; measure resistance between two conductors; low reading indicates good insulation.
• B. Apply a voltage between conductor and another conductor; read current; high current indicates good insulation.
• C. Use a megger to measure insulation temperature.
• D. With power off and components released; apply test voltage between conductor and ground; read insulation resistance; high reading indicates good insulation; low reading indicates leakage.

Answer: (D)