Surge Arrestor on Cables Entering an Outdoor Substation
Surge Arrestor on Cables Entering an Outdoor Substation
(OP)
We have a 100m section of 132kV cable entering into an outdoor substation. At one end the cable is connected to an OHL. Surge arrestors have been installed at the cable sealing ends. The other end the cable terminates into a bay feeder and no surge arrestors have been installed. All other bays connected to the substation are either 132kV OHL’s or transformers, all fitted with surge arrestors. The feeder bay supplying the cable has a line side disconnect switch that may occasionally be open. I will need to confirm that reflections will not cause the voltage to exceed the BIL rating of the cable, with a safety margin.
The question I have is it recommended or normal practice to install surge arrestors at the cable sealing end in the substation to protect the cable against overvoltages from within the substation, say a lightning stike on the busbars etc.
The question I have is it recommended or normal practice to install surge arrestors at the cable sealing end in the substation to protect the cable against overvoltages from within the substation, say a lightning stike on the busbars etc.






RE: Surge Arrestor on Cables Entering an Outdoor Substation
- shield wire criss crossing the substation space at top or
- the lightning masts with spikes mounted on top.
This should address the apprehension about the lightning strike in the switchyard that could affect the power cable.
However, I think there should be surge arrestors at the interface between cable and open conductor, irrespective of the availability of surge arrestors in the outgoing OHL feeders. This is important considering that the HV cables are expensive.
Trust the above is helpful.
RE: Surge Arrestor on Cables Entering an Outdoor Substation
RE: Surge Arrestor on Cables Entering an Outdoor Substation
It is an important point in insulation coordination you touched. Thanks.
RE: Surge Arrestor on Cables Entering an Outdoor Substation