Conductors in parallel

From Electrical Installation Guide

Conductors of the same cross-sectional-area, the same length, and of the same material, can be connected in parallel.

The maximum permissible current is the sum of the individual-core maximum currents, taking into account the mutual heating effects, method of installation, etc.

Protection against overload and short-circuits is identical to that for a single-cable circuit.

The following precautions should be taken to avoid the risk of short-circuits on the paralleled cables:

• Additional protection against mechanical damage and against humidity, by the introduction of supplementary protection
• The cable route should be chosen so as to avoid close proximity to combustible materials