High Current Arc Movement in a Narrow Insulating Channel

an experimental study has been performed to determine the arc speed and hesitation time of a high current arc inside a narrow insulating channel with a set of diverging copper arc runners and copper contacts. The dependence of arc speed on current, on diverging angle, and on runner width has been obtained. The results are qualitatively consistent with simple force considerations. Hesitation time (the time the arc remains immobile tH) is influenced by current and by runner width, both of which affect the magnetic force on the arc. The dependence of tHon contact opening speed leads to the concept of minimum gap for which the arc will start to move.