Method and Apparatus for Power Extraction in a Pre-Existing AC Wiring Infrastructure

摘要

A method and apparatus for extracting power in a switch location, and in a load location for use in a pre-existing infrastructure of switching AC power to a lamp (or other load) via a two terminal switch device. The switch is replaced with a module including a first controlled switch (such as a triac or relay) and a first impedance (such as a capacitor) connected in parallel, and another module including a second controlled switch (such as a triac or relay) and a second impedance (such as a capacitor) connected in parallel, is installed at the load location. In an ‘off’ state where the two controlled switches are in ‘open’ state, current is flowing via the impedances, but not through the load, so that power extractor circuits in the modules, connected in series to the impedances, extract low power for DC powering logic and other loads in the modules.

主权项

1. A system for controlling a powering of an AC load connected via first and second terminals from an AC power source connected via third and fourth terminals, the second terminal is connected to the third terminal, for use with a wire connecting fifth and sixth terminals, the system is configured to be in distinct first and second states and comprising first and second electrical circuits,
the first circuit comprising:
a first switch controlled to pass current in a ‘close’ state and to stop current flow in an ‘open’ state; anda first impedance connected in parallel to the first switch,wherein the first circuit is connected between the fourth and fifth terminals, the second circuit comprising:a second switch controlled to pass current in an ‘open’ state and to stop current in a ‘close’ state; anda second impedance,wherein the second switch is connected between the sixth and first terminals, and the second impedance is connected between the sixth and second terminals, and wherein in the first state the first and second switches are controlled to be in the ‘open’ state so that a first AC current is conducted from the AC power source via the first and second impedances, and in the second state the first and second switches are controlled to be in the ‘close’ state so that a second AC current is conducted from the AC power source via at least the first and second switches and the AC load.