Installation of Rail Foot Cables

Published 20 Jan 2020

Installation of rail foot cables

Installation of rail foot cables

Installation

Lay the cable down outside the area of the tracks and align it.

When doing so the cable must not be unwound over the flange of the delivery drum. In that case loops will occur which cannot be compensated during the lay. Lay the cable along the external side of the rail foot. When installing the cable, ensure that there is a reserve length of approximately 5 metre on each side.

If local conditions are met, the cable may also be laid directly along the external side of the rail foot from a slow moving railcar. Installation of the rail foot cable and fastening to the rail foot should take place from one end only or from the middle towards both ends. If installation is attempted from both ends, loops will occur in the cable. In this case damage to the cable by passing trains could not be ruled out.

At earthings, points, track magnets, level-crossings or in the case of a necessary joint the rail foot cable should be led away from the track with the help of a rail foot junction authorised and released by the rail operator. The cable should then be laid in the ground or in cable troughs, or at least be placed inside a protective pipe. For this procedure the minimum bending radius of the cable, as stipulated by the manufacturer, must be observed.

The placing of cable joints directly at the rail foot is not permitted.

Instead the cable ends to be joined must be led away from the rail foot and brought together in a sleeve next to the tracks.

Installation of rail foot cables

Ideal installation of rail foot cables

Inadequate installation creates loops

Inadequate installation creates loops

Fastening Cables

The cable may only be fastened with rail foot clamps which are approved for the particular type of track, since the permissible downward pressure is dependent on the type of cable and the track shape.

We recommend allowing one rail foot clamp in at least every second sleeper spacing and never fitting more than one single cable under the rail foot clamps at the rail foot.

In principle the installation of two rail foot cables under one rail foot clamp is possible. Special attention need to be paid to the diameter of the cable and the guidelines of the manufacturer of rail foot clamps. A combination of very small with larger rail foot cables shall be avoided as the expansion of both cables due to temperature changes are different and will result in loops. Furthermore the smaller cable shall always be installed on top.

Inadequate installation creates loops of the lower cable

Inadequate installation creates loops of the lower cable

Installation of Rail Foot Cables

Installation of Rail Foot Cables

Further Reading

Cable Terminations

Cable Pulling Equipment

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