scope:

This standard applies to London Underground maintained equipment only.

This standard applies to 10kHz overlay rail circuits, and to de-energised rail circuits using blockjoints. It does not apply to mechanical treadles or to electromagnetic position detectors.

The functions and performance criteria for track circuit based train detection systems are detailed in E7055, Train detection systems, and their maintenance requirements are specified in E7159, Maintenance of track circuits,

This standard is primarily intended for use by the Asset Steward.

This updated standard replaces E7154 A2, which is withdrawn.

Purpose

This standard defines the minimum maintenance requirements for rail circuits and associated equipment used on London Underground.

Rail circuits are safety critical assets, typically used to enable the safe clearing of signals or the safe releasing of routes.