A load control device for controlling the intensity of a lighting load, such as a light-emitting diode (LED) light source, may include a power converter circuit operable to receive a rectified AC voltage and to generate a DC bus voltage, a load regulation circuit operable to receive the bus voltage and to control the magnitude of a load current conducted through the lighting load, and a control circuit operatively coupled to the load regulation circuit for pulse width modulating or pulse frequency modulating the load current to control the intensity of the lighting load to a target intensity. The control circuit may control the intensity of the lighting load by pulse width modulating the load current when the target intensity is above a predetermined threshold and control the intensity of the lighting load by pulse frequency modulating the load current when the target intensity is below the predetermined threshold.

An emergency LED lighting system maintains power to an LED lighting source based on measured voltages and currents provided to the LED lighting source; rolls back or decreases power provided to an LED lighting source over time in order to increase the amount of time the battery can power the LED lighting source; executes a soft start procedure, such that the power provided to the LED lighting source is gradually ramped up during activation of the LED lighting sources; identifies a type of battery coupled to the emergency LED lighting system; cycles the emergency LED lighting system between charging mode and standby mode to reduce power consumption over a window of time; detects AC power or an absence of AC power; and/or uses a status LED to communicate information about the emergency LED lighting system with a remote device.

A lighting relay panel may include lower-cost features or components related to improved safety and reliability. In some cases, the relay panel includes a power supply capable of protecting the panel from high-voltage and high-current transients. A microcontroller may determine a power interruption based on a zero-cross signal received from the power supply, and may also configure latching relays during the interruption. In some implementations, the relay panel includes a relay sense circuit that is capable of receiving actuation signals from multiple relays connected to different phases of a power signal, and the microcontroller may synchronize or repeat the actuations based on a signal from the relay sense circuit. The microcontroller may generate relay addresses based on the relay positions within the relay panel. In some cases, the relay panel may include isolation circuits that are capable of providing an isolated control signal having an improved voltage range.

A load control device for controlling the intensity of a lighting load, such as a light-emitting diode (LED) light source, may include a power converter circuit operable to receive a rectified AC voltage and to generate a DC bus voltage, a load regulation circuit operable to receive the bus voltage and to control the magnitude of a load current conducted through the lighting load, and a control circuit operatively coupled to the load regulation circuit for pulse width modulating or pulse frequency modulating the load current to control the intensity of the lighting load to a target intensity. The control circuit may control the intensity of the lighting load by pulse width modulating the load current when the target intensity is above a predetermined threshold and control the intensity of the lighting load by pulse frequency modulating the load current when the target intensity is below the predetermined threshold.

A load driver for driving a load and an LED module are disclosed. In one embodiment, the load driver comprises a converter circuit comprising a controllable switching element configured to be turned on and off and to perform power factor correction for power from a power supply to the load, wherein a control terminal of the controllable switching element is configured for receiving a startup current via the two output terminals, the controllable switching element configured to be turned on by the startup current. The converter circuit further comprises a first inductor, coupled to the power supply at a first end, and to ground at a second end via the controllable switching element, wherein a first one of the output terminals connects to a second end of the first inductor via a diode forwarded from the first inductor, a second one of the output terminals is coupled to the first end of the first inductor.

A circuit arrangement for the electrical wiring of a light unit of a headlight for a vehicle, having a control unit which is connected to a power supply, the light unit having at least one semiconductor light source and a temperature measurer, wherein the semiconductor light source has a cathode and wherein the temperature measurer has a cathode, and wherein the light unit has an equipotential bonding contact. In the light unit, the cathodes are electrically connected to one another and/or at least one of the cathodes is electrically connected to the equipotential bonding contact in the light unit.

A circuit arrangement for the electrical wiring of a light unit of a headlight for a vehicle, having a control unit which is connected to a power supply, the light unit having at least one semiconductor light source and a temperature measurer, wherein the semiconductor light source has a cathode and wherein the temperature measurer has a cathode, and wherein the light unit has an equipotential bonding contact. In the light unit, the cathodes are electrically connected to one another and/or at least one of the cathodes is electrically connected to the equipotential bonding contact in the light unit.

A wiring device and method that control an amount of power delivered to a load, which maintain function even if a line connection and a load connection are reverse wired. Designed circuitry comprising steering diodes in both a line and a load wire direct a power source to an AC/DC power supply. The wiring device comprises a housing, a line terminal nominally designated for receiving electrical power from a power source, a load terminal nominally designated to feed electricity to a load, a neutral terminal, a line wire electrically connected to the line terminal, a load wire electrically connected to the load terminal, and a means for controlling an amount of power delivered to the load. Embodiments of the present invention include automated universal lighting controls, dimers, timers, and wired lighting devices.

A processor-based device includes a chassis having a chassis ground node that is arranged to electrically couple the chassis to an earth ground. The device also includes a connector accessible from an exterior of the chassis. The connector conforms to a standardized powerline interface having a hot power signal, a load power signal, and a neutral power signal. A processor-based apparatus housed at least in part within the chassis is arranged to operate using DC power derived from AC power present at the powerline interface. A stray voltage detector is arranged to detect a stray voltage potential existing between the neutral power signal of the standardized powerline interface and the chassis ground node, and the processor-based device is arranged to communicate at least one indication of the detected stray voltage potential.

An emergency LED lighting system maintains power to an LED lighting source based on measured voltages and currents provided to the LED lighting source; rolls back or decreases power provided to an LED lighting source over time in order to increase the amount of time the battery can power the LED lighting source; executes a soft start procedure, such that the power provided to the LED lighting source is gradually ramped up during activation of the LED lighting sources; identifies a type of battery coupled to the emergency LED lighting system; cycles the emergency LED lighting system between charging mode and standby mode to reduce power consumption over a window of time; detects AC power or an absence of AC power; and/or uses a status LED to communicate information about the emergency LED lighting system with a remote device.