What is the minimum value of the permitted test result for the insulation resistance test of a three-phase, 400V, mains cable?

What is the minimum value of the permitted test result for the insulation resistance test of a three-phase, 400V, mains cable?

• A. 2MΩ
• B. 1MΩ
• C. 0.5MΩ
• D. 3MΩ

Answer: (B)

The minimum permitted value for the insulation resistance test of a three-phase, 400V mains cable is 1MΩ. This standard ensures that the insulation of the cable is sufficient to prevent electrical leakage and maintain safety. Insulation resistance is critical in ensuring that electrical systems operate safely and effectively, as inadequate insulation can lead to faults, electrical shocks, and equipment damage. The specified minimum of 1MΩ is a widely accepted standard that provides a baseline for acceptable insulation resistance. Values below this threshold indicate the potential for insulation failure, which is not acceptable for reliable and safe electrical installations. Therefore, ensuring that insulation resistance meets or exceeds this value is essential for electrical safety and compliance with regulations.

The minimum permitted value for the insulation resistance test of a three-phase, 400V mains cable is 1MΩ. This standard ensures that the insulation of the cable is sufficient to prevent electrical leakage and maintain safety. Insulation resistance is critical in ensuring that electrical systems operate safely and effectively, as inadequate insulation can lead to faults, electrical shocks, and equipment damage.

The specified minimum of 1MΩ is a widely accepted standard that provides a baseline for acceptable insulation resistance. Values below this threshold indicate the potential for insulation failure, which is not acceptable for reliable and safe electrical installations. Therefore, ensuring that insulation resistance meets or exceeds this value is essential for electrical safety and compliance with regulations.