To perform an insulation resistance test of...

To perform an insulation resistance test of...

Question 1 of 270705eccefa4bacbc34ba4d483ff

To perform an insulation resistance test of an individual electric motor winding, where should the megohmmeter leads be connected?

Question 1 of 27070

Q

To perform an insulation resistance test of an individual electric motor winding, where should the megohmmeter leads be connected?

🔍 Key Concepts

• Purpose of an insulation resistance (megger) test on a motor winding • What part of the motor is considered ‘ground’ or ‘earth’ in this context • Difference between testing between conductors vs conductor to ground

💭 Think About

• Ask yourself: When checking the insulation quality of a winding, what exactly are you trying to see leakage to? Another conductor, or ground/frame? • Which connection choice actually tests if the winding is safely insulated from the metal parts a person could touch? • Eliminate any options that only measure resistance within the copper winding instead of between the winding and its surroundings.

✅ Before You Answer

• Verify which part of the motor is the metal, non-current-carrying part that should not have continuity to the winding. • Check which choice creates a test path from the live winding to that metal part to measure insulation resistance. • Make sure the selected option is consistent with standard practice: megger tests are usually done between conductor and ground, not just between two points on the same conductor.