Testing Medium-Voltage Metal-Enclosed Switchgear for Internal Arcing Faults
|Publication Date:||7 December 2001|
This guide establishes a method by which metal-enclosed switchgear, as defined by IEEE Std C37.20.2-1999 and IEEE Std C37.20.3-2001, can be tested for resistance to the effects of arcing due to an internal fault. This guide applies only to equipment utilizing air as the primary insulating medium and rated above 1000 V ac. It applies to both indoor and outdoor equipment; however, special consideration must be given to the building size and construction for indoor applications (not addressed by this guide).
The tests and assessments described in this guide are only applicable to arcing faults occurring entirely in air within the enclosure when all doors and covers are properly secured. This guide does not apply to arcing faults that occur within a component of the switchgear assembly, such as instrument transformers, sealed interrupting devices, fuses, etc.
Switchgear designs that meet the requirements of this guide will be referred to as arc-resistant metal-enclosed interrupter switchgear or arc-resistant metal-clad switchgear as applicable, or, generally, as arc-resistant switchgear.