1 Scope
This part of IEC 60947 covers low-voltage arc quenching devices, hereinafter referred to as AQDs, which are intended to eliminate arc-faults in low-voltage assemblies (typically
low-voltage switchgear and controlgear assemblies in accordance with the 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, connected to the main circuit, 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:
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• sensors intended to detect arc-faults;
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• devices intended to trigger the functioning of the arc quenching device;
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• devices intended to interrupt arc-fault current;
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• special requirements for AQDs for use in explosive atmospheres (e.g. ATEX).