Which test assesses whether insulation resistance is sufficiently high?

Which test assesses whether insulation resistance is sufficiently high?

• A. Continuity Test
• B. Dielectric Breakdown Test
• C. Dielectric Withstanding Test
• D. Insulation Resistance Test

Answer: (C)

The test that directly checks how well insulation resists leakage is the insulation resistance test. It uses a megohmmeter to apply a DC voltage between conductors (or between conductors and ground) and measures the resistance in megohms. A high resistance reading means little leakage current and good insulation; a low reading signals leakage paths due to moisture, contamination, or damage, indicating insulation isn’t sufficient. This is different from a continuity test, which only confirms a complete conductive path, and from dielectric breakdown or dielectric withstanding tests, which stress insulation with high voltage to see if it fails, rather than measuring its resistance.

The test that directly checks how well insulation resists leakage is the insulation resistance test. It uses a megohmmeter to apply a DC voltage between conductors (or between conductors and ground) and measures the resistance in megohms. A high resistance reading means little leakage current and good insulation; a low reading signals leakage paths due to moisture, contamination, or damage, indicating insulation isn’t sufficient. This is different from a continuity test, which only confirms a complete conductive path, and from dielectric breakdown or dielectric withstanding tests, which stress insulation with high voltage to see if it fails, rather than measuring its resistance.