LV Bare Conductors
LV Bare Conductors
(OP)
Gents,
if an underground 11kv feeder cable screen from substation is earthed and bonded to existing bare LV neutral on pole approx 120m from substation and then a fault occurred along overhead LV conductors,could the fault be seen by feeder's protection relay ?
Many thanks,
if an underground 11kv feeder cable screen from substation is earthed and bonded to existing bare LV neutral on pole approx 120m from substation and then a fault occurred along overhead LV conductors,could the fault be seen by feeder's protection relay ?
Many thanks,






RE: LV Bare Conductors
RE: LV Bare Conductors
RE: LV Bare Conductors
Probably not, Probably the safest. You don't want a service may to encounter a serious voltage difference between the local ground/neutral and the screen and drain conductors.
BUT. In a neglected system where grounds are missing and are in poor condition, part of a fault current may find its way back through the cable screen via the station end ground. Not likely but possible.
Bill
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"Why not the best?"
Jimmy Carter
RE: LV Bare Conductors
RE: LV Bare Conductors
But the current induced from the screen current in the main 11 KV circuit will be negligible so no protection will "see" the fault.
The L.V. current flowing through the 11 KV cable screen could heat the cable indeed ,so a good grounding electrode has to be provided at the screen connection pole and to connect the cable screen directly to this ground instead of LV neutral directly.
RE: LV Bare Conductors
RE: LV Bare Conductors
It is normal to ground the cable shield at every transformer, where it naturally gets connected to the LV ground.
RE: LV Bare Conductors
RE: LV Bare Conductors
RE: LV Bare Conductors
RE: LV Bare Conductors