What is the main goal of the insulation resistance test?

The primary objective of the insulation resistance test is to check for insulation failure. This test is designed to evaluate the effectiveness of insulation in electrical systems, ensuring that it can prevent current from leaking to earth or to other conductive materials. By applying a high voltage to the insulation and measuring the resistance, technicians can determine whether the insulation is intact or if there are any weaknesses, such as cracks or moisture ingress, that could lead to a breakdown.

A high insulation resistance reading indicates that the insulation is functioning correctly and providing adequate protection against accidental contact with live parts. Conversely, a low resistance value can signal impending insulation failure, allowing for corrective actions to be taken before any hazardous conditions develop. This testing is critical for maintaining safety and reliability in electrical installations.

While other options listed may relate to aspects of electrical testing, they do not specifically address the core purpose of evaluating insulation integrity, which makes this option the most relevant choice.