Arc fault causes pressure rise in the switch cabinet to damage equipment and harm people nearby.Because SF6 gas produces serious greenhouse effect

the influences of different substitutive insulating gases on the pressure rise due to internal arc fault were investigated in this study to reduce the usage of SF6.Many experiments were carried out to reveal the pressure rise in a chamber filled with nitrogen or carbon dioxide

and the energy transfer coefficient（kp） of each substitutive gas was calculated. Results showed that the pressure rise was greater in nitrogen than in carbon dioxide under the same arc energy

the pressure rise and kpincreased with the initial gas pressure of experimental vessel

the kpwas bigger in carbon dioxide than in nitrogen under the same arc current. These findings are conducive to better understanding and utilization of alternative gases N2 and CO2

to redue the amount of SF6 used.