When multiple conductors are bundled together, what happens to their current-carrying capacity?

When multiple conductors are bundled together, their current-carrying capacity generally decreases. This phenomenon occurs primarily due to the increased heat generated in a confined space. Each conductor generates heat when carrying current, and when these conductors are grouped closely together, the heat cannot dissipate effectively into the surrounding environment.

As a result of this temperature rise, the conductors may reach their maximum temperature ratings more quickly, leading to a reduced ability to carry the same amount of current safely without risking overheating. To counteract this issue, electrical codes often provide derating factors for bundled conductors. These guidelines help ensure that the installed wiring system can handle the electrical load safely without exceeding temperature limits.

Understanding the factors affecting current capacity in bundled conductors is crucial for ensuring safe and efficient electrical installations.