Short-line fault interruption capability of vacuum circuit breakers

Current zero measurements are performed during short-line fault interruption tests of vacuum circuit breakers. Various reignition modes (occurring between 0 and 75 ms after current zero) were observed due to insufficient arcing time. The (single) restrike and the (single) failure occurred with higher current than rated. The relationship between post-arc current/charge, reignition mode and TRV are discussed in this paper. All interrupters succeeded to interrupt at first or second current zero under the 'rated' conditions of short-line fault current and TRV.