In article , tangerine3
@toyotamail.com says...

Most homes have a 100A to 200A main breaker. Industrial buildings and
farms often have a 300A or 400A main. Factories with lots of electrical
machinery have multiple main panels, (often 3 phase), but what is the
largest main breaker that is sold?


For the the power company's high voltage electric lines, it is called a
"Recloser". Also when the voltage increases, the amperage decreases, so
these are not rated at very high amperages, but are rated for high
voltages...

http://en.wikipedia.org/wiki/Recloser


http://power.indiabizclub.com/catalo...ecloser~madras