Question 309Electricity & Electronics - Assistant Engineer

The correct answer is B) bad insulation. A low resistance reading when conducting a high potential (megger) test on motor coils would indicate that the insulation between the coils and ground is compromised or defective. This is because good insulation should have a very high resistance to ground, and a low reading signifies a fault or breakdown in the insulation integrity. The other answer choices are incorrect because: A) A high slot discharge factor is not directly related to the insulation resistance measured during a megger test. C) High insulation power factor is also not indicated by a low resistance reading, which points to bad insulation. D) Good insulation would result in a high resistance reading, not a low one.