scope:

The scope of this document covers requirements related to Network Rail 750 V rated d.c. controlled switchgear devices suitable for use in d.c. traction systems. Where this document references 750 V equipment, the requirements are equally applicable to lower voltage d.c. traction systems, including those operating at 630 V or 660 V.

These specific requirements, in addition to the general requirements of BS EN 50123, cover the following equipment types used by Network Rail as part of their 750 V d.c. distribution switchgear:

a) Circuit breakers;

b) Switches and disconnectors; and,

c) Short circuit switches and disconnectors.

The scope of this document specifically excludes depot short circuiting devices. The specification follows the requirements identified within the applicable British Standard, BS EN 50123-1:2003 Railway applications - Fixed installations - D.C. switchgear.

Purpose

The purpose of this document is to define the specific requirements for Network Rail's 750 V d.c. switchgear, in accordance with the framework provided by the applicable British Standard BS EN 50123 parts 1 - 4, 6, 7 Railway applications - Fixed installations - D.C. Switchgear. It will mitigate the risks of:

• Unclear requirements leading to difficulties in procuring switchgear components
• Increased costs from different Routes and projects working to different sets of requirements
• Non-compliance of procured components to BS EN 50123.