scope:

This document describes a method by which a train's compatibility with HVI track circuits used on Railtrack's a.c. and d.c. electrified infrastructure can be assessed.

Purpose

The purpose of this document is to provide a methodology to demonstrate compatibility of trains with HVI track circuits on the a.c. and d.c. railways on Railtrack controlled infrastructure. This is achieved by:

• Providing a model of the infrastructure for the a.c. and d.c. railways

• Providing a methodology for taking the line current recordings and using the infrastructure model producing a corresponding rail to rail voltage at the receiver

• Defining a methodology to play the rail to rail voltage into a HVI receiver

• Defining the criteria for the demonstration of compatibility

These elements form the basis of a test for checking the compatibility of trains with HVI track circuits.