Doco Overboard
Ultimate Member
Yes the sf6 switches or substation transformer fuses would melt out.
Thing is once that happens with fuses, they have to be closed manually but once that happens you have to isolate the feeders from the buss and then pick up the load through the breakers or disconnects one at a time which takes time ie walk the line out and visually inspect, get a target for trouble location where the fault current developed , do LOTO etc.
The other thing is if over current develops on the distribution side of a system, the breakers isolate the load from the substation transformer to protect the coils and LTC inside of it if it has one, if the high side fuses blow or melt out the HV or transmission lines them selves feeding the sub can absorb high amounts of induced pressure (volts) because theirs no current on them that is fed into the transformer.
Length diameter and type of construction and material is what someone was asking about earlier. Thats ampacity. You can place 40,000 volts on a piece of wire the diameter of a hair but it would have to be flow and current otherwise known as amps to melt it.
The biggest danger to electrical systems right now is terrorism, storms or component failure.
Electricity as whole is a theory not a science.
