scope:

This Standard applies to all nominal 630V d.c. and 750V d.c. circuits derived from traction substations. The d.c. Traction Supply system nominal voltage shall be 630V or 750V as defined in LU Standard 1-122 for the various Underground Lines, which includes the range of operating voltages to be expected. For the purposes of this standard, „d.c. circuits‟ and „d.c. protection‟ systems refer to these nominal voltages throughout this standard.

Excluded from the scope of this Standard is the calibration and maintenance of protection equipment.

This Standard applies to all new installations in its entirety and to existing installations where the necessary hardware exists to enable full compliance.

Purpose

The purpose of this Standard is to define the requirements for the determination of protection settings and for the commissioning of d.c. protection systems to ensure that protection systems will function correctly for the conditions specified in this Standard.