Lightning Outages on 25kV Underground Distribution System
Lightning Outages on 25kV Underground Distribution System
(OP)
Lightning frequently causes outages on 25kV overhead systems.
Has anyone heard of lightning causing outages on 25kV underground systems?
Has anyone heard of lightning causing outages on 25kV underground systems?






RE: Lightning Outages on 25kV Underground Distribution System
If the shields are grounded at both ends and the shield is wired through the CT it can cause tripping problems also (but that's a wiring mistake).
RE: Lightning Outages on 25kV Underground Distribution System
RE: Lightning Outages on 25kV Underground Distribution System
On other hand, the cables BIL are usually higher than OHTL so it is rare that a lightning wave will propagate past a line towards a cable without flashing the overhead line insulators.
One case may occur is a ground inducted current (due to nearby lightning discharge) with high di/dt causing induced voltage on the sheath and core as well?, I am not aware of the magnetic model for cables but can say that if the sheath is solidly (two points) grounded, you should not worry about it.