A system and methodology are provided for improving telemetry over a three-phase electrical power cable of the type used to provide power to electric submersible pumping systems or other powered devices. Data communication is provided between one end of a three-phase electrical power cable coupled with an electric power source and the other end of the three-phase electrical power cable coupled to a powered device, such as an electrical motor. The system and methodology enable a reduction in the level of common mode noise generated by, for example, a variable speed drive and/or enable minimizing or eliminating the common mode noise before mixing with data communication signals.