DANSK DSF/FPREN IEC 60947-9-1 PDF

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)