Included in the railroad’s original investment in electrification were 42 electric locomotives, 30 for freight and 12 for passenger service. Ordered from General Electric Company, which built the electrical components, and American Locomotive Company, which built the mechanical part, these 42 locomotives, each capable of developing 4,050 horsepower, consisted of two semi-permanently coupled cab units. Delivered between 1915 and 1917, they have proved themselves lasting tributes to the men who designed and built them, as well as those who have operated and maintained them. Although changing motive power requirements have brought modification of the units, 23 of the original 84 single units were still available for use when the phase-out was announced.
Subsequent purchases in 1920 and 1950 brought the total number of electric locomotives acquired to 128. As late as 1960, 98 of those units were still operating.
Several of the original units were altered at various times, some having cab and pilot wheels removed for use as non-control units, some rebuilt as shorter freight units, and some redesigned and modified for streamlined passenger service.
Originally designated EP-1 and EF-1, the first GE-Alco units are today used in various combinations of two, three or four cab and cabless units, as switchers, helpers and local freight locomotives with the designations EF-2, EF-3, ES-3 and EF-5.
The first electric locomotive to arrive on the system was No. 10200, proudly heralded by the railroad and the builders as the largest electric locomotive in the world. Not only was it the largest, but it was the first direct current electric locomotive to operate at a potential as high as 3,000 (later 3,400) volts, and the first to employ regenerative braking.
This same unit, perhaps the oldest working locomotive in the country, is still available for service in Deer Lodge, Mont. as No. E-5OAB.