Which test helps detect nicked or crushed insulation and checks isolation between parts of a circuit?

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

Answer: (A)

This question is about testing insulation under voltage stress to verify that different parts of a circuit stay electrically isolated from each other. A hipots test applies a high voltage between conductors (or between a conductor and ground) and monitors leakage current. If insulation is nicked or crushed, even a small flaw creates a leakage path that becomes detectable when the voltage is increased, causing leakage current to rise or the test to trip. That visibility of leakage under high voltage confirms that the insulation is still able to keep parts of the circuit properly isolated.

Dielectric breakdown tests push insulation to failure deliberately and can damage it, which is not what you want for routine isolation verification. Dielectric withstanding tests are basically another way to describe high-voltage stress tests, but in practice hipots is the term most commonly used for this purpose. An insulation resistance test uses lower voltage to measure resistance and detects gross deterioration, but it doesn’t stress the insulation the way a hipots test does, so it can miss mechanical damage like nicking or crushing.