Mitigation of arc-flash hazards and reduction of costs by selective arc-flash protection

This paper describes causes and characteristics of arc-flash faults, and gives an overview of existing arc-flash protection methods. The methods include e.g. arc-resistant switchgear, bus differential protection, zone selective interlocking, current limiting devices, and optical sensing based protection. Criteria of evaluation of the methods are proposed. The preferred dual-sensing methodology is explained more in detail. Current approaches to prevent arc-flash incidents and existing ultra-fast arc eliminators are introduced.