BS EN IEC 60947-9-1:2019

What is BS EN IEC 60947-9-1 - Arc quenching devices about?

BS EN IEC 60947-9-1 is the first part of an international standard that focuses on low-voltage switchgear and control gear. 

BS EN IEC 60947-9-1 covers low-voltage arc quenching devices hereinafter referred to as AQDs, which are intended to eliminate arc-faults in low-voltage assemblies, 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 1000V AC or 1500V DC.  

Note 1: BS EN IEC 60947-9-1 does not cover: 

• Sensors intended to detect arc-faults 
• Devices intended to trigger the functioning of the arc quenching device 
• Devices intended to interrupt arc-fault current 
• Special requirements for AQDs for use in explosive atmospheres (e. g. ATEX) 

Who is BS EN IEC 60947-9-1 - Arc quenching devices for?

BS EN IEC 60947-9-1 on arc quenching devices is useful for: 

• Manufacturers and suppliers of circuit breakers, arch quenching switchgear 
• Dealers and distributors of circuit breakers, arch quenching switchgear 
• Designers of circuit breakers, arch quenching switchgear  
• Test providers for circuit breakers, arch quenching switchgear 

Why should you use BS EN IEC 60947-9-1 - Arc quenching devices?

Protection against the effects of internal arc-faults can be achieved through passive components (containment) or through active components, known as "active arc-fault mitigation systems". 

BS EN IEC 60947-9-1 serves the purpose to set the requirements for arc quenching devices so that the necessary safety is ensured, and their performance can be fairly assessed. 

BS EN IEC 60947-9-1 includes special requirements for environmental withstand like ambient temperature, damp heat, shock, vibrations are included, considering the high impact of a malfunction, either unwanted operation (creation of a short-circuit), or failure to operate.