A light string includes a controller and a plurality of colorful light beads. The controller is electrically connected with the light beads and an AC electric supply, and the light beads are connected in series. Two voltage supply lines power the light beads, and control signals from the controller are fused with the power signal and passed to the light beads via the negative pole. The control signal is recognized by each light bead and also passed to the next light bead in the series, to produce a change in the output of each light bead (e.g., color, flashing pattern, etc.). The light beads include three LEDs of different color and can produce seven different colors. Multiple light segments can be connected and controlled by the same controller. The light string design is simple, yet versatile, offering many illumination outputs selectable by a user.

A light string includes a controller and a plurality of colorful light beads. The controller is electrically connected with the light beads and an AC electric supply, and the light beads are connected in series. Two voltage supply lines power the light beads, and control signals from the controller are fused with the power signal and passed to the light beads via the negative pole. The control signal is recognized by each light bead and also passed to the next light bead in the series, to produce a change in the output of each light bead (e.g., color, flashing pattern, etc.). The light beads include three LEDs of different color and can produce seven different colors. Multiple light segments can be connected and controlled by the same controller. The light string design is simple, yet versatile, offering many illumination outputs selectable by a user.

Hazard detector for providing a pre-alarm of a developing hazardous condition can include a detection module that detects a hazard level of smoke or carbon monoxide, a light source that generates light, a speaker that generates an audible sound, a horn that generates an audible alarm that a higher volume than the speaker, and a processing module. The processing module can receive the detected hazard level and compare it with the pre-alarm threshold and the emergency threshold. The processing module can determine that the hazard level is greater than the pre-alarm threshold and less than the emergency threshold and cause an audible pre-alarm speech to be generated via the speaker that warns of the developing hazardous condition.

A two-way load control system comprises a power device, such as a load control device for controlling an electrical load receiving power from an AC power source, and a controller adapted to be coupled in series between the source and the power device. The load control system may be installed without requiring any additional wires to be run, and is easily configured without the need for a computer or an advanced commissioning procedure. The power device receives both power and communication over two wires. The controller generates a phase-control voltage and transmits a forward digital message to the power device by encoding digital information in timing edges of the phase-control voltage. The power device transmits a reverse digital message to the controller via the power wiring.

A path light control device that can include a processor and light source, and any combination of ambient light sensors (ALS), passive infrared (PIR) sensors, accelerometers and compass sensors, where the sensor sampling mode and sampling period may be dynamically determined to permit the ALS to accurately measure an ambient light without excessive operation. The accelerometer and compass sensor may be provided to determine device movement and orientation to avoid sensor operation when movement or orientation of the device indicates that the data of the sensor is not applicable for proper device control.

A solid-state circadian rhythm lamp and related control techniques are disclosed. The lamp may have a night/pre-sleep emissions mode in which it emits light having a correlated color temperature (CCT) of about 1,800-2,300 K, the spectral power ratio of blue light (400-495 nm) being such that it constitutes about 10% or less of the total light emitted. The lamp may have a day/wakeup emissions mode in which it emits light having a CCT of about 5,000-8,000 K, the spectral power ratio of blue light being such that it constitutes about 30% or more of the total light emitted. The lamp may have a general lighting mode in which it produces a combined light output having a CCT of about 2,500-5,000 K. The lamp driver may support emissions mode changing based on hysteresis relating to a lighting switch associated with a power socket hosting the lamp.

A system of light devices including a first light device and a second light device. The first light device having a first housing, a first light, a first transceiver, a first electronic processor. The second light having a second housing, a second light, a second transceiver, a second electronic processor. The first electronic processor is coupled to the first light and the first transceiver, and configured to control operation of the first light, and transmit, via the first transceiver a command to the second light device. The second electronic processor coupled to the second light and the second transceiver, and configured to receive, via the second transceiver, the command from the first light device, and change an operational parameter of the second light in response to the command from the first light device.

Networked intelligent lighting devices may utilize visual light communication to perform autonomous neighbor discovery, for example, as part of a map generation process. Individually, each intelligent lighting device within an installation transmits a series of packets via visual light communication for receipt by one or more of the other intelligent lighting devices. Receiving intelligent lighting devices record the number of received packets from each transmitter. Records of numbers of received packets are conveyed via a data communication network to a centralized process. The centralized process utilizes the conveyed records to determine neighbor relationships between lighting devices, for example to generate a map of devices as located within the installation.

A two-way load control system comprises a power device, such as a load control device for controlling an electrical load receiving power from an AC power source, and a controller adapted to be coupled in series between the source and the power device. The load control system may be installed without requiring any additional wires to be run, and is easily configured without the need for a computer or an advanced commissioning procedure. The power device receives both power and communication over two wires. The controller generates a phase-control voltage and transmits a forward digital message to the power device by encoding digital information in timing edges of the phase-control voltage. The power device transmits a reverse digital message to the controller via the power wiring.

A particular smart hazard detector may itself function as a guide during a process of installation of the same at an installation location. Additionally, the installation location of the particular smart hazard detector may play a central role in how various settings of the smart hazard detector are defined and adjusted over time.