Types of Signalling Systems

There are two types of signalling methodologies traditional/conventional Fixed block signal or CBTC based Moving Block signalling. Fixed block signalling arose when the first track circuit was invented. The track circuit allowed signalling engineers to break the track into small manageable chunks but what was revolutionary in 1867 is a bottleneck in the new millenium. Moving block signalling is a concept that grew out of the CBTC world because it removed the need for track circuits as the primary mechanism for detecting traina. Since track circuits forced signal engineers into a fixed block mindset, removing track circuits liberated designers into a brave new world of moving block signalling. This video compares and describes the two signalling methodologies. Naeem Ali CBTC Specialist Director & Principal Consultant CBTC Solutions Inc. CBTCSolutions.ca