BS 7197:1990

Specifies bonds for connecting the metallic envelopes of electric power cables at terminations and joints. Gives performance test methods and tables cross-sectional area of solid copper, aluminium and steel bonds together with guidance on bonding.

This British Standard specifies requirements for bonds for connecting the metallic envelopes (protective conductors) of electric power cables at terminations and joints for system voltages up to 36 kV for the different types of cables covered by British Standards.

The standard describes performance test methods, tables cross-sectional areas of solid copper, aluminium and steel bonds calculated in accordance with a given formula and gives guidance on matters which affect the following.

1. Provision of a circuit in joints between cables and between a cable and its terminal equipment for the transmission of currents which may arise under system fault conditions.
2. Provision of bonding for neutral conductors (CNE only).
3. Provision of overall protective conductors at joints to provide for the passage of a fault current in the event of mechanical damage or failure of the insulation and to contain the electric field around high voltage conductors.

Guidance on bonding is given in Appendix A.

The standard specifically excludes additional safety precautions necessary when jointing live cables.

NOTE The title of the publication referred to in this standard is given on the inside back cover.