Patent ID: 8373547

Claim:
A method for using power-line phase-cut signaling to change energy usage for one or more devices sharing a common power signal, comprising: detecting a phase-cut notch in the common power signal at a first device, wherein an upstream device receives a request to change power usage, wherein in response to the request, the upstream device inserts the phase-cut notch into the common power signal, wherein the first device is located downstream from the inserted phase-cut notch; and triggering a power-state change in the first device in response to the phase-cut notch in the common power signal; wherein a second device is controlled by a first switch and the first device is controlled by a second switch; wherein the first switch and the second switch are downstream from the inserted phase-cut notch; wherein a phase-cut detector is located downstream from the first switch; wherein the phase-cut detector can trigger a power relay that interrupts power for the first device; wherein if the request is received when both the first switch and the second switch are on, the phase-cut detector detects the phase-cut notch and triggers the power relay to disable the first device; and wherein if the request is received when only one of the first switch or the second switch are on, the states of the first device and the second device are not changed.