If insulation resistance test yields a very low resistance value, what does this indicate about insulation condition?

If insulation resistance test yields a very low resistance value, what does this indicate about insulation condition?

• A. Poor insulation with possible leakage.
• B. Good insulation.
• C. Test invalid.
• D. Insulation thickness increased.

Answer: (B)

A very low insulation resistance reading means there is a leakage path through the insulation. This shows the insulation is not effectively resisting current, which indicates poor insulation condition. Moisture, dirt, damaged or degraded insulation, or contamination can create that leakage path, allowing current to flow where it shouldn’t. It’s a warning sign that the insulation needs attention or repair. The test result isn’t about insulation thickness; thicker insulation wouldn’t cause a low resistance, and the reading isn’t inherently an invalid test—it’s simply telling you the insulation is compromised.

A very low insulation resistance reading means there is a leakage path through the insulation. This shows the insulation is not effectively resisting current, which indicates poor insulation condition. Moisture, dirt, damaged or degraded insulation, or contamination can create that leakage path, allowing current to flow where it shouldn’t. It’s a warning sign that the insulation needs attention or repair. The test result isn’t about insulation thickness; thicker insulation wouldn’t cause a low resistance, and the reading isn’t inherently an invalid test—it’s simply telling you the insulation is compromised.