Distributed Power - History

History

Since the 1960s, railroad distributed power technology has been dominated by one company, Harris Controls (originally Harris Corporation—Controls and Composition Division, later purchased by General Electric, and now known as GE Transportation Systems Global Signalling), who have manufactured and marketed a patented radio-control system known as Locotrol that is the predominant (perhaps only?) wireless distributed power system in use today around the world.

With its origins in the early days of SCADA technology for the remote control of pipelines and electric utilities, and from an early concept of Southern Railway President D.W. Brosnan, Locotrol was a product of the North Electric Company (Galion, Ohio) which was later purchased by Radiation Inc. (Melbourne, Florida) and—in turn—purchased by Harris Corporation (also headquartered in Melbourne, FL), and was first tested on the Southern Railway in 1963. The first production Locotrol was installed on the Southern Railway in 1965.

In the early years of this technology, Wabco also had—for a relatively brief period—a competing system called 'RMU' (Remote Multiple Uniter) which was installed on a few North American railroads. However this system did not prevail and soon went out of production. Prior to the advent by North Electric of the proprietary 'LOCOTROL' name, the product was referred to as 'RCE' (Radio Controlled Equipment) or 'RCS' (Radio Control System) and the lead and remote units as 'master' and 'slave'. The colloquial 'master' and 'slave' terms, though, were not formally used by the manufacturer. In some U.S. railroad parlance, Locotrol trains are referred to as 'radio trains'.