Breakdown strength of nitrogen at high temperatures

IN A-C circuit-interrupting devices, the post-arc period immediately after current zero is of paramount importance. This period is characterized by the rapid cooling and deionization of the hot gases between the contacts, which build up the dielectric strength of the gap. Simultaneously, however, the circuit transients resulting from the interruption of the current impose a rapidly increasing voltage across the contact gap. This so-called recovery voltage may break down the gap and re-establish the arc.