The Pennsylvania Railroad's class O1 comprised eight experimental boxcab

electric locomotive An electric locomotive is a locomotive powered by electricity from overhead lines, a third rail or on-board energy storage such as a battery or a supercapacitor. Locomotives with on-board fuelled prime movers, such as diesel engines or g ...

s built in 1930 and 1931. They were built in preparation for the New York to Washington Electrification project. They had the

wheel arrangement In rail transport, a wheel arrangement or wheel configuration is a system of classifying the way in which wheels are distributed under a locomotive. Several notations exist to describe the wheel assemblies of a locomotive by type, position, and c ...

classified as

4-4-4 Under the Whyte notation for the classification of steam locomotives, 4-4-4 represents the wheel arrangement of four leading wheels on two axles, four powered and coupled driving wheels on two axles, and four trailing wheels on two axles. In th ...

in the

Whyte notation Whyte notation is a classification method for steam locomotives, and some internal combustion locomotives and electric locomotives, by wheel arrangement. It was devised by Frederick Methvan Whyte, and came into use in the early twentieth cen ...

( UIC: 2'B2'; AAR: 2-B-2). Although successful, they were not powerful enough for the railroad's increasingly heavy trains. For production, the PRR chose to concentrate on the P5 class, effectively an enlarged and more powerful version of the O1 with an additional pair of driving wheels. The eight locomotives were divided into four sub-classes — O1, O1a, O1b, and O1c. Each sub-class was fitted with a different combination of

traction motor A traction motor is an electric motor used for propulsion of a vehicle, such as locomotives, electric or hydrogen vehicles, elevators or electric multiple unit. Traction motors are used in electrically powered rail vehicles ( electric multiple ...

power output and drive

gear ratio A gear train is a mechanical system formed by mounting gears on a frame so the teeth of the gears engage. Gear teeth are designed to ensure the Pitch circle diameter (gears), pitch circles of engaging gears roll on each other without slipping, pr ...

. In addition, three O1 locomotives were fitted with

General Electric General Electric Company (GE) is an American multinational conglomerate founded in 1892, and incorporated in New York state and headquartered in Boston. The company operated in sectors including healthcare, aviation, power, renewable en ...

equipment, three with Westinghouse, and two with

Brown Boveri Brown, Boveri & Cie. (Brown, Boveri & Company; BBC) was a Swiss group of electrical engineering companies. It was founded in Zürich, in 1891 by Charles Eugene Lancelot Brown and Walter Boveri who worked at the Maschinenfabrik Oerlikon. In 1970 ...

. The O1b locomotives used a

Buchli drive The Buchli drive is a transmission system used in electric locomotives. It was named after its inventor, Swiss engineer Jakob Buchli. The drive is a fully spring-loaded drive, in which each floating axle has an individual motor, that is placed in ...

between the traction motors and the driving wheels. were used, with two motors geared to each axle. They were generally employed in pairs by sub-class, generally on short-distance passenger trains between

Newark, New Jersey Newark ( , ) is the most populous city in the U.S. state of New Jersey and the seat of Essex County and the second largest city within the New York metropolitan area.New York City New York, often called New York City or NYC, is the most populous city in the United States. With a 2020 population of 8,804,190 distributed over , New York City is also the most densely populated major city in the Un ...

Pennsylvania Station Pennsylvania Station (often abbreviated Penn Station) is a name applied by the Pennsylvania Railroad (PRR) to several of its grand passenger terminals. Several are still in active use by Amtrak and other transportation services; others have been ...

. During

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...

they were used on the "Susquehannock" between Harrisburg, Pennsylvania and New York City. Later in life, they were used for transfer work around Penn Station and

Sunnyside Yard Sunnyside Yard is a large coach yard, a railroad yard for passenger cars, in Sunnyside, Queens in New York City. Description The yard is owned by Amtrak and is also used by New Jersey Transit. The shared tracks of the Long Island Rail Road (LIR ...

, mostly hauling empty passenger stock. They were all out of service and scrapped by the mid 1960s.

References

{{PRR locomotives O1 11 kV AC locomotives 4-4-4 locomotives Experimental locomotives Passenger locomotives Electric locomotives of the United States Standard gauge locomotives of the United States Scrapped locomotives