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AssigneePhilips Lighting Holding B.V.
InventorGeorge Bradley MILLS
Estimating the term…
A system (and system controller) has powering of, and communication with, a set of fixtures using an AC cable having a power line (e.g. a mains live wire), a reference line (e.g. a mains neutral wire) and a data line. Fixtures are at different positions along the cable, each powered by the local voltage difference between the power line and the reference line. A system controller provides a data signal over the data line, wherein the data signal for a fixture is defined by the local voltage difference between the data signal on the data line and the reference line (or power line). In order to compensate for voltage drops, a compensation circuit adds a voltage offset waveform to the data signal which is dependent on the overall set of positions of the fixtures. This enables an increased number of fixtures and/or reach of the fixtures connected to the system controller.
A system controller for powering and communicating with a set of fixtures using an AC cable comprising a power line, a reference line and a data line, and adapted to communicate with fixtures at different positions along the cable and each powered by the local voltage difference between the power line and the reference line, wherein the system controller comprises:
A method of powering a set of fixtures, each of which is connected to an AC cable comprising a power line, a reference line and a data line and positioned at different positions along the cable, powered by the local voltage difference between the power line and the reference line, wherein the method comprises:
Dependencies are inferred from the claim text.