Purpose. The resonant overvoltage arises in main electrical networks as a result of random coincidence of some parameters of circuit and its mode and it may exist for a relatively long time. Therefore. the traditional means of limitation of short duration commutation surges are not effective in this case. https://www.bekindtopets.com/best-buy-Selle-CHROMAG-OVERTURE-Rails-CrMo-Violet-amazing-save/