Head End Power Unit Configurations for Passenger Trains
In the late 1990s, the American Public Transportation Association (APTA), implemented practices for Head End Power sources throughout the passenger rail industry.
According to 3.1.3 in APTA RP-R-015-99, Head End Power (HEP) is defined as “A system by which 480 VAC 3-phase electrical power, to operate auxiliaries, is provided to railroad vehicles from a central source via a trainline system. The power source can be locomotive (hence “Head End”), power car, or wayside source.” Read more