Dielectric Phase in an SF6 Model Breaker

In SF6 circuit breakers the arcing region is stressed by the applied recovery voltage after current interruption. A channel of hot gas of reduced density can be observed at the place where the arc has burnt. The spatial and temporal development of this hot gas channel and its temperature have been investigated under various experimental conditions using a model breaker. The results are compared to theoretical calculations describing the temperature decay in the upstream region of a double flow arrangement during the dielectric phase.