BS EN IEC 60947-9-2:2025

1 Scope This document covers internal arc-fault control devices, hereinafter referred to as IACD, which are intended to:

detect internal arc-faults in low-voltage switchgear and controlgear assemblies, by processing (at a minimum) the optical effect of an internal arc-fault, and
operate mitigation device (either external or combined)

in order to minimize the effects of the internal arc-fault (see Figure 1). For the purpose of this document the terms "light" or "optical" covers more than visible spectra. They may cover also, for example, infrared or ultraviolet electromagnetic radiations (see Annex D). For combined-type IACD, this document is considered in addition to the relevant product standard for internal arc-fault mitigation devices (IARD per IEC TS 63107:2020 ). Compliance to the relevant product standard is mandatory and cannot be claimed by testing to this document alone. NOTE 1     Low-voltage switchgear and controlgear assemblies are usually described by <span class="std" data-id="d2471e912" data-type="unda...