Abstract:
A load control device, such as an electronic ballast, for controlling the power delivered from an AC power source to an electrical load, such as one or more fluorescent lamps, comprises a power converter having an inductor and a power switching device coupled to the inductor, a load control circuit adapted to be coupled to the electrical load, and a control circuit operable to calculate an average input power of the load control device. The control circuit may be operable to calculate a cumulative output power of the power converter while the ballast is preheating filaments of the lamps, and to subsequently determine a fault condition in the lamps in response to the calculated cumulative output power of the power converter. Further, the control circuit may be operable to transmit a digital message including the calculated average input power of the load control device.
Abstract:
A method of automatically programming a new load control device that replaces an old load control device takes advantage of a remote identification tag (e.g., an RFID tag) located in the vicinity of the old device. The remote identification tag stores an identifier that is representative of a location in which the old device is installed. The method includes the steps of: (1) storing a setting of an old device in a memory of a controller; (2) associating the setting with the identifier of the old device in the memory of the controller; (3) the new device retrieving the identifier from the remote identification tag after the new device is installed in the location of the old device; (4) the new device transmitting the identifier to the controller; and (5) the controller transmitting the setting of the old device to the new device in response to receiving the identifier.
Abstract:
A controllable electrical outlet may comprise a resonant loop antenna. The resonant loop antenna may comprise a feed loop electrically coupled to a radio-frequency (RF) communication circuit and a main loop magnetically coupled to the feed loop. The controllable electrical outlet may comprise one or more electrical receptacles configured to receive a plug of a plug-in electrical load and may be configured to control power delivered to the plug-in electrical load in response to an RF signal received via the RF communication circuit. The RF performance of the controllable electrical outlet may be substantially immune to devices plugged into the receptacles (e.g., plugs, power supplies, etc.) due to the operation of the resonant loop antenna. For example, degradation of the RF performance of the controllable electrical outlet may be less when the controllable electrical outlet includes the resonant loop antenna rather than other types of antennas.
Abstract:
A load control device for controlling the intensity of a light source (e.g., a light-emitting diode light source) reduces visible flickering in the light source when a target intensity of the light source is dynamically changing. The load control device includes a load regulation circuit operable to conduct a load current through the electrical load and to control the amount of power delivered to the electrical load. The load control device also includes a controller for adjusting the average magnitude of the load current to a target current. The controller pulse-width modulates the magnitude of the load current between a first current less than the target current and a second current greater than the target current. When the target current is dynamically changing, the controller is operable to adjust to the average magnitude of the load current towards the sum of the target current and a supplemental signal.
Abstract:
A load control device for controlling the amount of power delivered to an electrical load (e.g, an LED light source) comprises an isolated forward converter comprising a transformer, a controller, and a current sense circuit operable to receive a sense voltage representative of a primary current conducting through to a primary winding of the transformer. The primary winding is coupled in series with a semiconductor switch, while a secondary winding is adapted to be operatively coupled to the load. The forward converter comprises a sense resistor coupled in series with the primary winding for producing the sense voltage that is representative of the primary current. The current sense circuit receives the sense voltage and averages the sense voltage when the semiconductor switch is conductive, so as to generate a load current control signal that is representative of a real component of a load current conducted through the load.
Abstract:
A load control device for controlling the amount of power delivered to an electrical load (e.g., an LED light source) includes first and second semiconductor switches, a transformer, a capacitor, a controller, and a current sense circuit operable to receive a sense voltage representative of a primary current conducting through to a primary winding of the transformer. The primary winding is coupled in series with a semiconductor switch, while a secondary winding is adapted to be operatively coupled to the load. The capacitor is electrically coupled between the junction of the first and second semiconductor switches and the primary winding. The current sense circuit receives a sense voltage and averages the sense voltage when the first semiconductor switch is conductive, so as to generate a load current control signal that is representative of a real component of a load current conducted through the load.
Abstract:
A load control device for controlling the amount of power delivered to an electrical load (e.g., an LED light source) comprises an isolated forward converter comprising a transformer, a controller, and a current sense circuit operable to receive a sense voltage representative of a primary current conducting through to a primary winding of the transformer. The primary winding is coupled in series with a semiconductor switch, while a secondary winding is adapted to be operatively coupled to the load. The forward converter comprises a sense resistor coupled in series with the primary winding for producing the sense voltage that is representative of the primary current. The current sense circuit receives the sense voltage and averages the sense voltage when the semiconductor switch is conductive, so as to generate a load current control signal that is representative of a real component of a load current conducted through the load.
Abstract:
A method of automatically programming a new load control device that replaces an old load control device takes advantage of a remote identification tag (e.g., an RFID tag) located in the vicinity of the old device. The remote identification tag stores an identifier that is representative of a location in which the old device is installed. The method includes the steps of: (1) storing a setting of an old device in a memory of a controller; (2) associating the setting with the identifier of the old device in the memory of the controller; (3) the new device retrieving the identifier from the remote identification tag after the new device is installed in the location of the old device; (4) the new device transmitting the identifier to the controller; and (5) the controller transmitting the setting of the old device to the new device in response to receiving the identifier.
Abstract:
A load control device, such as an electronic ballast, for controlling the power delivered from an AC power source to an electrical load, such as one or more fluorescent lamps, comprises a power converter having an inductor and a power switching device coupled to the inductor, a load control circuit adapted to be coupled to the electrical load, and a control circuit operable to calculate an average input power of the load control device. The control circuit may be operable to calculate a cumulative output power of the power converter while the ballast is preheating filaments of the lamps, and to subsequently determine a fault condition in the lamps in response to the calculated cumulative output power of the power converter. Further, the control circuit may be operable to transmit a digital message including the calculated average input power of the load control device.