Substation 7 is a

traction substation A traction substation, traction current converter plant, rectifier station or traction power substation (TPSS) is an electrical substation that converts electric power from the form provided by the electrical power industry for public utility ...

located at 1782 Third Avenue at 99th Street in the East Harlem neighborhood of

Manhattan Manhattan (), known regionally as the City, is the most densely populated and geographically smallest of the five boroughs of New York City. The borough is also coextensive with New York County, one of the original counties of the U.S. state ...

. The

Manhattan Railway Company The Manhattan Railway Company was an elevated railway company in Manhattan and the Bronx, New York City, United States. It operated four lines: the Second Avenue Line, Third Avenue Line, Sixth Avenue Line, and Ninth Avenue Line. History 19 ...

built it in order to electrify the Second, Third and Ninth Avenue elevated lines. It served as a power source for the

IRT Lexington Avenue Line The IRT Lexington Avenue Line (also known as the IRT East Side Line and the IRT Lexington–Fourth Avenue Line) is one of the lines of the A Division of the New York City Subway, stretching from Lower Manhattan north to 125th Street in Eas ...

from 1918 until the 1970s. It originally converted 25 Hz AC power from the 74th Street power station, to DC for the electric motors. The substation is owned by the MTA and it is listed on the

National Register of Historic Places The National Register of Historic Places (NRHP) is the United States federal government's official list of districts, sites, buildings, structures and objects deemed worthy of preservation for their historical significance or "great artistic ...

References

Buildings and structures on the National Register of Historic Places in Manhattan East Harlem Former power stations in New York City New York City Subway infrastructure Third Avenue {{NYC-transport-stub