What must be measured to prevent current leakage effectively?

To effectively prevent current leakage, insulation resistance is the key measurement. Insulation resistance refers to the resistance offered by the insulation materials that separate the live conductors from each other and from the ground. High insulation resistance indicates that the insulation is intact and functioning properly, preventing unwanted paths for electrical current that could lead to leakage.

When insulation deteriorates due to age, environmental factors, or mechanical damage, it can allow current to pass through the insulation, which can be hazardous, leading to shock risks, equipment damage, or fire hazards. By measuring insulation resistance using a specialized instrument like a megohmmeter, you can evaluate whether the insulation is suitable for safe operation.

Other measures mentioned, such as phase sequence, earth fault loop impedance, and continuity testing, do serve significant roles in electrical installations. However, they do not specifically address the prevention of current leakage in the same direct manner as insulation resistance testing does. Understanding and maintaining proper insulation resistance is essential for ensuring electrical safety and system integrity.