Dependence of Arc Interrupting Capability on Spatial Distribution of Airflow Velocity in Air-Blast Flat-Type Quenching Chamber

The dependence of an interrupting capability on the spatial distribution of airflow velocity was investigated in an air-blast flat-type quenching chamber. To obtain various distributions of airflow velocity, the axial position of a nozzle and the inlet width of the nozzle were varied. For each of the axial positions and each of the inlet widths, arc interruption tests for ac currents were performed to measure the interrupting capability. The distributions of airflow velocity in the quenching chamber were calculated intentionally in the absence of the arc. From the test and the calculation results, we found a definite relationship between the velocity distribution and the interrupting capability.