For cable sizing following factors to be taken into consideration :
(a) Voltage drop in cable during starting of equipment(cable manufacturers provide voltage drop of cable in per ampere /per km basis so drop can easily calculated by just multiplying load in amperes )
(b) Short circuit...
If CT's are placed on line side then how will it be taken for maintenance . CT,s are mounted on transformer where it is required by customer. CT is are also in the line as well as transformer and busduct.
CT just defines the zone you want to protect. As it is in case of Transrupter self powered...
The best location is load side of transrupter . Because in future for any maintenance purpose you can easily open the trans rupter and work on CT's , If on line side of transrupter CT's are place you have to shut the line down for CT maintenance.
I have never seen surge arrester in GSU Transformer neutral . Surge arresters are always tapped from phases.Since Transformer is Wye on HV side no use of surge arrester in neutral. Regarding current flowing in all the metallic structures it seems strange , but check the resistance values of...