A power control device is provided for adjusting the input power to a device. The power control device includes an input, an output, and two or more output levels. A device such as an electrical device, appliance, or tool is attached to the output of the power control device. Further, a switch couples the input of the power control device to a power source. Thereby, the output level of the power control device can be adjusted by turning on and turning off the power source within a period of time.

A two-level LED security light with a motion sensor. At night, the LED security light is turned on for a low level illumination. When the motion sensor detects any intrusion, the LED security light is switched from the low level illumination to a high level illumination for a short duration time and then returns to the low level illumination for saving energy. The LED security light includes a power supply unit, a light sensing control unit, a motion sensing unit, a loading and power control unit, and a lighting-emitting unit and at least one external control unit electrically coupled to a controller of the loading and power control unit to receive and convert at least an external control signal into a message signal interpretable by the controller for adjusting at least an operating parameter or changing at least an illumination mode of the two-level LED security light.

A lifestyle LED security light including a light-emitting unit configured with two sets of LED loads respectively emitting different color temperature lights is disclosed. At dusk the light-emitting unit is automatically turned on for a first level illumination with a low color temperature light featuring an aesthetic night view with the motion sensor being deactivated for a time duration, and then the light emitting unit is changed to a second level illumination and at the same time the motion sensor is activated, wherein when the motion sensor detects a motion intrusion, the light-emitting unit is instantly switched to perform a third level illumination with a a high light intensity and a high color temperature light. The color temperatures of the first level illumination and the third level illumination are respectively adjustable by simultaneously and reversely adjusting the electric powers respectively allocated to the two sets of LED loads.

A security light technology to configure an automatically setting timer used for selecting and operating a light-on duration activated by a motion sensor is disclosed. The disclosed uses a shutoff transition mode to eliminate a hassle or hardship caused by an unexpected shutoff of illumination. The shutoff transition mode also serves a communication interface between the motion sensor and an occupant remaining in a detection space such that the occupant can interrupt the shutoff transition mode. The disclosed uses a software algorithm to detect and learn the motion characteristics of occupants in the detection space and thereby to automatically set a timer to operate the light-on duration triggered by a motion intrusion. The disclosed also teaches a dual mode motion sensing light configured with a short timer to manage a pathway illumination and a long timer to manage an occupancy illumination bridged by the shutoff transition mode.

A two-level LED security light includes a light-emitting unit comprising at least an LED load which may be turned on or turned off by a light sensing control unit. A motion sensing unit upon an intrusion detection activates the LED load to generate a high level illumination for a time length adjustable by a time setting unit. The LED load is operated in compliance with a power supply unit wherein a voltage V across each LED is confined in a range V.sub.th<V<V.sub.max, with V.sub.th a threshold voltage and V.sub.max a maximum voltage. The light-emitting unit may be configured with two LED lighting loads emitting lights with different color temperatures, wherein a power allocation circuitry may be installed to respectively distribute different electric powers to the two LED loads to manage a color temperature tuning scheme thru a light diffuser.

A life-style two-level LED security light with a motion sensor. The life-style two-level LED security light includes a light-emitting unit configured with two sets of LEDs respectively emitting different color temperature lights. At night, the light-emitting unit is turned on for a low level illumination with a low color temperature light featuring an ascetic night view. When the motion sensor detects a motion intrusion, the light-emitting unit is switched from the low level illumination with the low color temperature light to a high level illumination with a high color temperature light to perform a dual effect of security alert and to enable an occupant to have a high visibility of the surrounding environment when needed. The low level illumination also creates a light house effect to help an occupant move toward a destination without encountering an accident or getting lost.

An LED security light includes a light emitting unit, at least one sensing unit, a loading and power control unit and a power supply unit configured with a first power source and a second power source, wherein a power level detector and a power switching circuitry are installed to select and connect at least one of the first power source and the second power source to the light emitting unit. The light emitting unit is activated at dusk and is deactivated at dawn. When the first power source is used, the LED security light generates a first level illumination. When the second power source is used, the LED security light generates a second level illumination. The first power source is a solar power while the second power source is a backup battery.

A two-level LED security light within it has a light-emitting unit including an LED load which may be turned on or turned off by a loading and power control unit activated by a light sensing control unit and a motion sensing unit. When the motion sensing unit detects a motion signal, the light-emitting unit is switched to a high level illumination for a predetermined time length adjustable by a time setting unit, and then the loading and power control unit manages to turn off the light-emitting unit thru a soft off process. The LED load is configured with a plurality of LEDs accommodating to the power supply unit wherein a voltage V across each LED is confined in a range V.sub.th<V<V.sub.max, with V.sub.th being a minimum voltage to turn on the LED and V.sub.max a maximum voltage to avoid damaging the LED.

There is provided a lighting controller for a luminaire (70, 71, 72, 73, 74, 75) in a room (50). The lighting controller comprises at least one switch (104, 106, 108, 110) adjustable to configure the lighting controller to operate in one of a first mode and a second mode. The lighting controller further comprises a receiver configured to receive a light level measurement for the room (10); a processor; and a memory comprising instructions. The instructions, when executed, cause the processor to: if the lighting controller is configured to operate in a first mode, output a first lighting control signal based on the light level measurement modified by a first factor; and if the lighting controller is configured to operate in a second mode, output a second lighting control signal based on the light level measurement modified by a second factor, different from the first factor.

A lighting system includes a control unit for controlling brightness level of a light source based on a photosensor output signal and a motion sensor output signal. The control unit may increase the brightness level of the light source as ambient light level decreases, or decreases the brightness level as the ambient light level increases. The control unit may also increase the brightness level to a maximum brightness level when motion is detected.