This standard gives supplementary requirements for low voltage switchgear and controlgear assemblies for public distribution transforming sub-stations. They are stationary, type tested assemblies (TTA) for installation in places where only authorised persons have access for their use, however, outdoor types may be installed in situations which may be accessible to the public. They are connected to the low voltage terminals of distribution transformers by means of connecting bars, rods or cables and are for use in low voltage public three phase systems. Individual components such as fuses and switching devices complying with other standards, shall also comply with the supplementary requirements of this standard. The object of this standard is to state the definitions and to specify the service conditions, construction requirements, technical characteristics and tests for Substation Cable Distribution Boards. Network parameters may require type tests at higher performance levels.