NR BR 13422 PDF

General

The power supplies required for 50 Hz single phase electric traction on British Rail are obtained generally from the 132 kV National Grid system although there are exceptions in some localities. The supplies are taken by the railway in duplicate as single phase current at 25 kV through 132/25 kV transformers supplied by the Supply Authority. These transformers are normally banked with existing Area Electricity Boards supply transformers utilizing a common 132 kV circuit breaker. The supplies from the Grid are provided through transformers in sizes ranging from 5 MVA to 26.5 MVA nominal capacity.