Thermal Current Interruption Performance of CO2 and CO2/C4F7N mixture

This contribution aims to compare the thermal interruption performance of pure CO2with a mixture CO2/C4F7N. Measurements primarily show higher interrupting capability for amixture with C4F7N. Detailed analysis shows distinct difference in failure mechanism which forCO2/C4F7N is and CO2 mostly “hot dielectric” failure. The failuremechanism relevant test duties most severe TRV. influence ablated nozzlematerial on process can be ruled out.