The PCM30U-OCH device is intended primarily for use in energy networks to build transmission paths between high-voltage line protective relays and for the reliable transmission of commands. In addition to this, the PCM30U-OCH transmits voice and data signals via all conventional types of interfaces. The device is optimised for transmission via fibre-optic cables along high-voltage power lines, but can also be used for connections via E1 or E2 transmission networks (PDH, SDH, RR) or E0 via PLC systems.

The main features of the PCM30U-OCH include the transmission of commands and digital signals, duplex transmission of 50 Hz signal, standard E1 multiplexing for analogue and digital services and SCADA, GPS synchronisation, effective use of the transmission path for commands independent of voice and data services.