Protection of Small Low-Voltage Conductors Against High-Level Faults

Abstract

In the majority of existing low voltage electrical distribution systems, there is lack of appropriate protection of small conductors (No. 3 AWG and smaller) against high fault currents. The reason for this is that a great number of electrical engineers are not following the necessary steps to ensure this protection, or they don’t have the necessary tools to evaluate the withstand ratings of small conductors. Deficient protection of small conductors against high-level fault currents could have devastating consequences. This article gives a step-by-step method to determine if a small conductor in a low voltage distribution system is properly protected against high-level fault currents.