A slave control device receives a communication signal from a master control device, and controls loads according to the received communication signal. A modulator superimposes the communication signal from the master control device on power source lines, and a demodulator demodulates the communication signal superimposed on the power source lines and supplies the demodulated communication signal to the slave control device. The modulator is provided on power source lines on a battery side, and the demodulator is provided on the power source lines on a load side. The modulator superimposes the communication signal on the power source lines which are on a side closer to the loads with respect to the modulator among the power source lines.

Method and apparatus for generating a power line communication (PLC) signal. In one embodiment, the method comprises generating a first modulation signal based on at least one data stream; modulating a first carrier signal by the first modulation signal to generate a first signal; generating a second signal by performing a phase shift based on the first signal; and coupling a balanced three-phase PLC signal comprising the first signal, the second signal and a third signal to a three-phase power line.

In described examples, a first isolation element electrically isolates a first circuit from a second circuit and passes AC signals between the first circuit and the second circuit. A second isolation element electrically isolates the first circuit from the second circuit and passes AC signals between the first circuit and the second circuit. A ground of the second circuit electrically floats relative to a ground of the first circuit, so that a digital signal is able to pass from the second circuit through a third isolation element to the first circuit. A supply voltage generation device converts AC signals from the first isolation element and the second isolation element into at least one DC voltage to power the second circuit.

A method for data transmission between a pump assembly (2) and a control device (8) is provided, wherein the pump assembly (2) for the energy supply is connected via at least one electrical supply lead (10) to a frequency converter (14). The data transmission is effected via the electrical supply lead (10), and an evaluation of a data transmission signal (34) received by the pump assembly (2) or the control device (8) is only effected in low-disturbance regions of a carrier signal (22) formed by a supply current. A pump system designed for carrying out this method is also provided.

An audio filtering and power extraction apparatus for filtering out audio signal and extracting power from a combined signal and direct-current power line, with an input configured to couple to a combined signal and direct-current power line, a filtering extractor system functionally coupled to the input, a DC sensing switch circuit, and a second order low-pass filter functionally coupled to the DC sensing switch circuit, the second order low-pass filter including, an inductor, a capacitor and resistor in series with each other, and an output functionally coupled to an output of the filtering extractor system and through which output extracted power is provided.

There is provided an appliance management apparatus including a connection state acquiring unit acquiring information generated due to an appliance terminal of an electronic appliance being positioned close to or connected to a power supplying terminal that supplies power, and a connection state management unit managing a connection state of the appliance terminal to the power supplying terminal using the information acquired by the connection state acquiring unit.

Disclosed is a transformer for power line communication, capable of performing power line communication without being influenced by voltage attenuation due to voltage conversion. The transformer for power line communication includes: a transforming unit configured to convert a high primary voltage into a low secondary voltage, or convert a low secondary voltage into a high primary voltage; a separation unit configured to separate a data signal from a primary voltage input thereto; and a coupling unit configured to couple the data signal with the low secondary voltage.

A first mobile device including a connection terminal configured to electrically connect to a second mobile device, a variable impedance device connected to the connection terminal, the variable impedance device configured to vary an impedance, processing circuitry configured to determine a power line communication (PLC) mode between the first mobile device and the second mobile device to be one of a low-speed PLC mode or a high-speed PLC mode, and control the impedance of the variable impedance device according to the determined PLC mode, and a PLC modem configured to receive power from the second mobile device or communicate data with the second mobile device based on the determined PLC mode.

There are provided systems, devices and methods for detection and/or prevention of power line communications. In particular, there are provided systems, devices, and methods for preventing and/or detecting the possibility to communicate with an end unit via power line communication.