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APTA PR-E-RP-017-99

27-Point Control and Communication Trainlines for Locomotives, Locomotive-Hauled Equipment and DMUs

Abstract

This document defines recommended practices for 27-point MU control and communication trainlines, including functional hardware and interfaces on the vehicles with circuit functions, for use on new/rebuilt locomotives, locomotive-hauled vehicles and DMUs.

Keywords: 27-point, communication trainline, control command, digital trainline, MU trainline, trainline

Summary

This recommended practice defines the functionality of 27-point MU and communication trainline systems, as well as their application to passenger cars, locomotives and DMUs.

Document History

Document Number Version Publication Date Publication Related Information
APTA PR-E-RP-017-99 Rev. 2 05/13/2026 Published Current
APTA PR-E-RP-017-99 Rev. 1 03/22/2004 Published Superseded

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