Solid State Interlocking (SSI) is the brand name of the first generation processor-based interlocking developed in the 1980s by British Rail's Research Division, GEC-General Signal and Westinghouse Signals Ltd in the UK.
Solid State Interlocking (SSI) is the brand name of the first generation processor-based interlocking developed in the 1980s by British Rail's Research Division, GEC-General Signal and Westinghouse Signals Ltd in the UK.