Abstract: A connecting device, system and method for use in an industrial installation is disclosed, which includes at least one first industrial bus interface configured to receive first industrial bus input data and transmit first industrial bus output data using a first industrial bus protocol, and a second industrial bus interface configured to receive second industrial bus input data and transmit second industrial bus output data using a second industrial bus protocol. A modulator is configured to produce first energy bus output data by modulating the first industrial bus input data onto an industrial Ethernet protocol and configured to produce second energy bus output data by modulating the second industrial bus input data onto the industrial Ethernet protocol. An energy communicator is configured to transmit the first and second energy bus output data together as an energy bus output signal on the energy supply line using a carrier frequency method.