Hi everyone,
in the HV Cable system, we have to install the link box for earthing purpose, however, the link box is having different types such as a) LB Direct earth b) LB with / without SVL, ..etc, the SVL (Sheath Voltage Limiter) is non linear resistance, designed to work as Fues (just an example) to discharge the induced voltage on the HV Cables, during normal operation it will be switched off while in the short circuit it will be switched on for discharging to the main earth.
to determine a sheath voltage limiter (SVL) should have a continuous operating voltage of Uc higher than the calculated voltage at the cable end.
my point is why to choose higher than calculated voltage and not the same or less as to choose higher than the calculated value could be not safe for the cable system.