scope:

This standard applies to all equipment and power supply wiring, from the point where it enters the room or apparatus case up to the point of supply for individual circuits, which is usually in the form of a feed fuse or circuit breaker.

The following list is a guide to the scope of this engineering standard:

a) all wiring, transformers, switching equipment and protecting equipment from the 600V AC signal main links or isolators to the feed bus bars, and to other power supply units;

b) low voltage supply units, and feeds from these to bus bars, including rectifiers for DC supplies;

c) uninterruptible power supplies;

d) 230V wiring from the room consumer unit to any signalling apparatus;

e) power supply units for any computer apparatus;

f) batteries.

Workshop overhaul is not covered by this standard.

This standard does not include the maintenance of Jointless Track Circuits power supplies, which are covered by engineering standard SCS-ST0058.

The maintenance of cable runs is covered by engineering standard E7163.

This standard supersedes E7157A3, which is withdrawn.

Purpose

This standard defines the minimum maintenance requirements for signalling power supplies.