Abstract:
A load control system controls a lighting load provided in a space and comprises a load control device and one or more occupancy sensors. The load control device controls the load in response to the wireless control signals received from the occupancy sensors. Each occupancy sensor transmits an occupied control signal to the load control device in response to detecting an occupancy condition in the space and a vacant control signal to the load control device in response to detecting a vacancy condition. The load control device adjusts the intensity of the load to a first intensity in response to receiving the occupied control signal from at least one of the occupancy sensors, and adjusts the intensity of the load to a second intensity less than the first intensity (e.g., a non-off intensity) in response to receiving vacant control signals from both of the occupancy sensors.
Abstract:
A mounting plate for a control device is adapted to be coupled to an electrical wallbox and is made of a non-conductive material. The mounting plate comprises at least one faceplate screw opening for receiving a faceplate screw such that a faceplate may be coupled to the mounting plate during installation. The mounting plate further comprises a ground wire. The ground wire is adapted to be coupled to earth ground and is also positioned to overlap a portion of the faceplate screw opening. During the installation of the faceplate, as the faceplate screw is inserted into the faceplate screw opening of the yoke, the faceplate screw contacts the ground wire as well as the faceplate. In the event that the faceplate is made of metal, the faceplate will be coupled to the ground wire, and thus, safely grounded.
Abstract:
A sensing device transmits wireless signals when an error between at least one sampled parameter value and at least one predicted parameter value is too great, such that the sensing device transmits wireless signals to a load control device using a variable transmission rate that is dependent upon the amount of change in a value of the parameter. The sensing device uses the one or more estimators to determine the predicted parameter value, and may transmit the estimators to the load control device if the error is too great. The load control device uses the estimators to determine at least one estimated parameter value and controls the electrical load in response to the estimated parameter value. The sensing device may comprise, for example, a daylight sensor for measuring a total light intensity in the space around the sensor or a temperature sensor for measuring a temperature around the sensor.
Abstract:
A sensing device transmits wireless signals when an error between at least one sampled parameter value and at least one predicted parameter value is too great, such that the sensing device transmits wireless signals to a load control device using a variable transmission rate that is dependent upon the amount of change in a value of the parameter. The sensing device uses the one or more estimators to determine the predicted parameter value, and may transmit the estimators to the load control device if the error is too great. The load control device uses the estimators to determine at least one estimated parameter value and controls the electrical load in response to the estimated parameter value. The sensing device may comprise, for example, a daylight sensor for measuring a total light intensity in the space around the sensor or a temperature sensor for measuring a temperature around the sensor.
Abstract:
A system for independent control of electric motors and electric lights includes a plurality of two-wire wallstations coupled in series via power wires between an alternating-current (AC) source and a light/motor control unit. The light/motor control unit is preferably located in the same enclosure as an electric motor and an electric light and has two outputs for independent control of the motor and the light. The light/motor control unit and the wallstations each include a controller and a communication circuit that is coupled to the power wiring via a communication transformer and communicate with each other using a loop current carrier technique. The light/motor control unit and the wallstations utilize pseudo random orthogonal codes and a median filter in the communication process.
Abstract:
A load control system controls an electrical load provided in a space and comprises a load control device and one or more occupancy sensors. The load control device controls the load in response to the wireless control signals received from the occupancy sensors. Each occupancy sensor transmits an occupied control signal to the load control device in response to detecting an occupancy condition in the space and a vacant control signal to the load control device in response to detecting a vacancy condition. The load control device turns on the load in response to receiving the occupied control signal from at least one of the occupancy sensors, and turns off the load in response to receiving vacant control signals from both of the occupancy sensors. The load control device is operable to determine that no wireless control signals have been received from the occupancy sensors for the length of a predetermined timeout period and to subsequently turn off the load.
Abstract:
A multiple location load control system comprises a main device and remote devices, which do not require neutral connections, but allow for visual and audible feedback at the main device and the remote devices. The main device and the remote devices are adapted to be coupled in series electrical connection between an AC power source and an electrical load, and to be further coupled together via an accessory wiring. The remote devices can be wired on the line side and the load side of the load control system, such that the main device is wired “in the middle” of the load control system. The main device is operable to enable a charging path to allow the remote devices to charge power supplies through the accessory wiring during a first time period of a half-cycle of the AC power source. The main device and the remote devices are operable to communicate with each other via the accessory wiring during a second time period of the half-cycle.
Abstract:
A wireless battery-powered daylight sensor for measuring a total light intensity in a space is operable to transmit wireless signals using a variable transmission rate that is dependent upon the total light intensity in the space. The sensor comprises a photosensitive circuit, a wireless transmitter for transmitting the wireless signals, a controller coupled to the photosensitive circuit and the wireless transmitter, and a battery for powering the photosensitive circuit, the wireless transmitter, and the controller. The photosensitive circuit is operable to generate a light intensity control signal in response to the total light intensity in the space. The controller transmits the wireless signals in response to the light intensity control signal using the variable transmission rate that is dependent upon the total light intensity in the space. The variable transmission rate may be dependent upon an amount of change of the total light intensity in the space. In addition, the variable transmission rate may be further dependent upon a rate of change of the total light intensity in the space.
Abstract:
A load control device is adapted to be disposed in series with an AC voltage source and an electrical load and is operable to provide substantially all voltage provided by the AC voltage source to the load. The load control device comprises a controllably conductive device, a controller, a zero-crossing detector, and a power supply for generating a substantially DC voltage for powering the controller. The power supply is operable to charge an energy storage device to a predetermined amount of energy each half-cycle. The controller is operable to determine when the power supply has stopped charging from the zero-crossing detector each half-cycle, and to immediately render the controllably conductive device conductive to conduct the full load current. Before the controllably conductive device begins to conduct each half-cycle, only a minimal voltage develops across the power supply to allow the energy storage device to charge.
Abstract:
A method for controlling the speed of an AC motor by means of an AC motor speed control having a plurality of capacitors operable to be selectively coupled in parallel electrical connection, the parallel coupled capacitors operable to be coupled in series electrical connection with the AC motor, the method comprising charging the capacitors up to substantially the same predetermined voltage prior to combining the capacitors in parallel electrical connection.