Energy-saving circuit for a network-powered device, network arrangement and energy-saving method

A network arrangement comprising:

• a supply unit (PSE) that recognizes and supplies network-powered devices (PD) with a supply voltage (VPSE),
• at least one network-powered device having an energy-saving circuit and a converter circuit that produces an operating voltage (VOUT) for the device from the supply voltage (VPSE), and
• at least one network cable which connects the supply unit (PSE) and the at least one network-powered device (PD) to one another;
• wherein the energy-saving circuit comprises:
• at least one switching element that breaks at least one electrical connection between the network cable and the converter circuit,
• at least one control circuit that actuates the at least one switching element on the basis of control signals that switch on and/or off and are received from the device, and
• at least one energy buffer that stores energy from voltages pulses, provided via the network, to supply the control circuit with an operating power.

An energy-saving method for a network-powered device comprising:

• storing electrical power from voltage pulses provided via a network in an energy buffer,
• operating a control circuit with power stored in the energy buffer,
• recognizing a first device-end control signal that switches on the network-powered device by the control circuit, and
• actuating a switching element by the control circuit to make an electrical connection between the network and a converter circuit of the network-powered device.