Apparatus, systems, and methods for remotely dimming lights are disclosed. In one embodiment, a light-dimming apparatus for placement within a lighting enclosure of a lighting fixture is disclosed. The light-dimming apparatus can comprise a plurality of input and output terminals, a dimmer module, one or more motion sensing modules, a fail-safe module, and a microcontroller unit comprising a plurality of wireless communication modules, and one or more processor cores. The one or more processor cores can be programmed to execute instructions to receive a dimming command from another device via at least one of the plurality of wireless communication modules, receive zero-crossing signals from the dimmer module, and transmit switching signals to the dimmer module to modulate the power supplied to the lighting load to dim the brightness of the lighting load.

System for determining periodic values of phase angle of waveform power input including voltage detector for detecting periodic values of average voltage of waveform power input and detecting corresponding periodic values of peak voltage of waveform power input. System also includes phase angle detector in signal communication for receiving periodic values of average voltage and peak voltage from voltage detector. Phase angle detector also detects periodic values each being ratio of one of periodic values of average voltage divided by corresponding periodic value of peak voltage, or being ratio of peak voltage divided by average voltage; and determines periodic values of phase angle of waveform power input corresponding to periodic values of ratio. Lighting systems.

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 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-wire load control device (such as, a dimmer switch) for controlling the amount of power delivered from an AC power source to an electrical load (such as, a high-efficiency lighting load) includes a thyristor coupled between the source and the load, a gate coupling circuit coupled between a first main load terminal and the gate of the thyristor, and a control circuit coupled to a control input of the gate coupling circuit. The control circuit generates a drive voltage for causing the gate coupling circuit to conduct a gate current to thus render the thyristor conductive at a firing time during a half cycle of the AC power source, and to allow the gate coupling circuit to conduct the gate current at any time from the firing time through approximately the remainder of the half cycle, where the gate coupling circuit conducts approximately no net average current to render and maintain the thyristor conductive.

Systems and methods for dimming control using TRIAC dimmers are provided. An example apparatus for a power conversion system includes: a process-and-drive component configured to receive an input signal and output a drive signal to a switch to affect a current that flows through a primary winding of a power conversion system. The input signal includes a first pulse associated with a first input period and a second pulse associated with a second input period. The drive signal is associated with a first modulation period for the first input period and a second modulation period for the second input period. The process-and-drive component is further configured to: determine the first modulation period for the first input period; change the drive signal between a first logic level and a second logic level at a modulation frequency during the first modulation period; determine the second modulation period for the second input period.

A load control device (such as, a dimmer switch) for controlling the amount of power delivered from an AC power source to an electrical load (such as, a high-efficiency lighting load) includes a thyristor (such as, a triac) coupled between the source and the load, a gate coupling circuit coupled to conduct current through a gate terminal of the thyristor, a controllable switching circuit coupled between the gate coupling circuit and the gate terminal of the thyristor, and a control circuit configured to control the gate coupling circuit and the controllable switching circuit. The control circuit may cause the gate coupling circuit to conduct a pulse of current through the gate terminal to render the thyristor conductive at a firing time during a present half cycle of the AC power source, and allow the gate coupling circuit to conduct at least one other pulse of current after the firing time during the present half cycle.

Systems and methods for dimming control using TRIAC dimmers are provided. An example apparatus for a power conversion system includes: a process-and-drive component configured to receive an input signal and output a drive signal to a switch to affect a current that flows through a primary winding of a power conversion system. The input signal includes a first pulse associated with a first input period and a second pulse associated with a second input period. The drive signal is associated with a first modulation period for the first input period and a second modulation period for the second input period. The process-and-drive component is further configured to: determine the first modulation period for the first input period; change the drive signal between a first logic level and a second logic level at a modulation frequency during the first modulation period; determine the second modulation period for the second input period.

A triac driving circuit according to an embodiment of the present disclosure includes a phototriac coupler, a first resistive element, and a second resistive element, which are connected in series to a gate terminal of a triac. A minimum resistance of the first resistive element including tolerance is higher than a maximum resistance of the second resistive element including tolerance.

[Object] To propose a control apparatus, a control system and a control method which are capable of causing another light source to adaptively emit light at a timing at which light emitted from one light source changes.

[Solution] A control apparatus including: a light source control unit configured to control light emission of a second light source on the basis of profile of light emitted from a first light source and a synchronization signal for synchronizing a timing between the first light source and the second light source for radiating light on a surgical region.