This section of IEC 1334-3 applies only to MV phase-to-phase isolated capacitive coupling devices for MV (medium voltage) distribution line carrier (DLC) systems. The coupling device ensures: a) the efficient transmission/reception of carrier-frequency signals between the DLCtransceiver and the power line; b) the safety of personnel and the protection of the low-voltage parts of the installation against the effects of the power-frequency voltage and transient overvoltages. The object of this section of IEC 1334-3 is to establish definitions, requirements, methods of testing and rated values for phase-to-phase isolated capacitive coupling devices to be used in MV-DLC systems.