HVI cable (high-voltage resistant insulated conductor) to maintain the separation distance from electrically conductive parts according to DIN EN 62305-3 (VDE 0185-305-3), in order to prevent dangerous discharges between components of the external lightning protection system and internal conductive parts (electrical installations, pipelines, etc.). To avoid sliding discharges, the HVI cable is equipped with an external special sheath that allows for the adjustment of high lightning impulse voltages against a reference potential. Design of HVI cable (pre-assembled for installation inside pipes, black) with a head piece and a grounding connection element. Equivalent separation distance s = 75 cm (in air), s = 150 cm (solid material).