Replacement
As the cost of electronics and signaling hardware fell with respect to the cost of labor, Automatic Block Signaling began to be replaced by Centralized Traffic Control and other systems that allowed trains to run in any direction on any track. Traffic control systems not only make use of bi-directional signaling, but also prevent trains being routed against the set flow of traffic at interlockings and automatically reduce all wrong direction automatic signals to an obstructed block state. This completely eliminates manual traffic setting procedures in bi-directional ABS schemes and wrong direction contingency procedures in single direction schemes.
Read more about this topic: Automatic Block Signaling
Famous quotes containing the word replacement:
“Not even the visionary or mystical experience ever lasts very long. It is for art to capture that experience, to offer it to, in the case of literature, its readers; to be, for a secular, materialist culture, some sort of replacement for what the love of god offers in the world of faith.”
—Salman Rushdie (b. 1947)