Arc Parameters in CO2-blast quenching chamber with high-pressure storage tank of different pressures

The present paper reports CO2 arc parameters just before a current-zero measured for a double-pressure type interrupting apparatus. The arc parameters before a current-zero were determined at the CO2 pressure in a high-pressure storage tank of 0.2–0.6 MPa. The increase in the high-pressure storage tank from 0.2 to 0.6 MPa raises the arc power loss from 0.32 to 0.78 kW and also decreases the arc time constant from 1.3 to 0.7 μs for a current with a peak value of 1.1 kA. On the basis of the measured arc parameters, the increase in an interrupting capability of the apparatus with the CO2 pressure was discussed. As a result, it was concluded that this increase in the interrupting capability resulted from the decrease in the arc time constant.