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American Railway Signaling Principles and Practices Electric Interlocking Chap19
American Railway Signaling Principles and Practices Electric Interlocking Chapter 19 XIX
Revised October 1950 , Copyright 1951
Approx 90 pages
Stapled
General.
Electric interlocking is a type of power interlocking, and as the name implies, electricity is the operating agency. The first machine was installed in America in 1888. The essential elements for a complete electric interlocking system are a source of electrical energy, a machine with its levers and auxiliary apparatus for controlling switch and signal mechanisms, and apparatus for preventing unauthorized movement of an operated unit.
In power interlocking, means are provided to check the correspondence of position of switch, signal or other unit controlled with the lever, and for preventing the unauthorized movement of the operated unit. The former is known as indication locking and the latter as cross-protection.
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