UNE-EN IEC 60947-9-1:2021

This document covers low-voltage arc quenching devices, hereinafter referred to as AQD, which are intended to eliminate arcing faults in low-voltage assemblies (typically low voltage switchgear and controlgear assemblies according to IEC 61439 series), by creating a lower impedance current path, to cause the arcing current to transfer to the new current path. This new current path is maintained until a short-circuit protection device (SCPD) interrupts the short-circuit current.

AQDs are installed in low-voltage assemblies, in derivation from the main distribution path, preferably as close as possible to all primary power sources.

Their rated voltage does not exceed 1 000 V AC or 1 500 V DC.

This document does not cover:

sensors intended to detect arcing fault;

devices intended to trigger the functioning of the arc quenching device;

devices intended to interrupt arcing fault currents;

special requirements for AQD for use in explosive atmospheres (e.g. ATEX).