Design of a new generation of internal arc resistant switchgear

As an internal arc fault cannot be ruled out completely, manufacturers are designing equipments to withstand internal arc faults. The standards for the requirements differ considerably for example the requirements of ANSI are not the same as for IEC. But the standards are continuing to evolve as this issue becomes more understood. The design of a new range of withdrawable metal-clad cubicle shall provide the maximum safety to operating personnel and cope up with different demands. These cubicles shall be built with segregated compartments, doors and front covers designed to withstand severe stresses without allowing the effects of the arc to come outside. The paper describes the development with respect to internal arc, both from an operational and and an operator safety point of view.