What is the maximum load for a conductor not to exceed the table value multiplied by what factor?

The maximum load for a conductor is determined to ensure safe and efficient operation, preventing overheating and potential failure. The value that should not be exceeded is typically calculated by applying a certain factor to the ampacity values provided in standard tables. In this context, the factor of 0.8 is used to represent a safety margin.

Using a factor of 0.8 means that the maximum continuous load on a conductor should be 80% of its rated capacity. This 20% reduction accounts for various conditions such as ambient temperature, conductor bundling, and other installation factors that could affect the performance of the conductor over time. By adhering to this factor, the electrical system is protected against overloads and the risk of overheating is significantly reduced, thereby ensuring safety and longevity of the electrical installation.

In contrast, applying a higher multiplier would suggest allowing a continuous load that could exceed the conductor's safe operating limits, which is not advisable from a safety and reliability standpoint.