Installing a remote control "DCS" in Union Pacific yard engines in 1:1 scale
Some railroads have installed DCS systems in yard engines to allow remote control of yard engines by yard crews for train makeup. The engines are operated by crews via handheld radio systems.
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The author is shown in the following photo while working as a DCS controls engineer at the Union Pacific Salt Lake City yard. The control system used at the Salt Lake City facility courtesy of the GE Harris Transportaion Company.