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APTA PR-E-RP-015-99

Head End Power Source Characteristics

Abstract

This recommended practice defines the characteristics necessary on new equipment for head end power (HEP) sources, including diesel-driven alternators, inverters and utility-supplied wayside power. The HEP source is composed of power source, switchgear, control system (incorporating trainline complete functions) and connections to vehicle HEP trainline(s).

Keywords: 480 Vac HEP, head end power source, TLC, trainline, trainline complete (TLC)

Summary

This recommended practice defines the functionality of HEP power sources and their control systems, including trainline interfaces.

Document History

Document Number Version Publication Date Publication Related Information
APTA PR-E-RP-015-99 Rev. 2 05/13/2026 Published Current
APTA PR-E-RP-015-99 Rev. 1 03/22/2004 Published Superseded

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