What signifies that insulation performance has degraded over time?

Decreased resistance signifies that insulation performance has degraded over time because it indicates that the insulation material is allowing more electrical current to flow through it than it should. In electrical systems, proper insulation is crucial for maintaining safe and efficient operation. Good insulation should have high resistance, meaning it effectively prevents electrical current from leaking through unwanted paths.

When resistance decreases, it can suggest that the insulation has been compromised due to factors such as age, temperature fluctuations, moisture ingress, or physical damage. This degradation can lead to increased risk of electrical faults, such as short circuits or electrical fires. Therefore, monitoring resistance levels and noticing a drop is essential for assessing the health of electrical insulation and preventing potential safety hazards.