Photocontrol for luminaire consumes very low power
AssigneeExpress Imaging Systems, LLC
InventorWilliam G. Reed
Life of this patent
Estimating the term…
Abstract
A photocontrol includes a switch that consumes very low power when the switch is turned ON and when it is turned OFF. The photocontrol can provide low-power digital control signals to high-impedance inputs of control devices that control the delivery of power to load devices, such as LED drivers that control the delivery of power to arrays of LEDs. The photocontrol also can provide power signals to control devices that control the delivery of power to light sources, such as electronic transformers that control the delivery of power to fluorescent lamps. The photocontrol may include a comparator that causes the photocontrol to have switching hysteresis.
Claims42
A photocontrol apparatus to provide a plurality of control signals to a high-impedance controller input used to control the delivery of power to a load device, the apparatus comprising:
- a switch including a first node, a second node, and a third node, the first node electrically, communicably coupled to a source of electrical power and the third node electrically, communicably coupled to the high-impedance controller input;
- and
- a photosensor electrically, communicably coupled between the second node and the third node, the photosensor operable to at least partially cause a voltage level of the second node with respect to a voltage level of the third node to change when the photosensor outputs current in response to being at least partially illuminated with light, wherein
- when the voltage level of the second node with respect to the voltage level of the third node is greater than a threshold voltage level, the third node outputs a first control signal, and
- when the voltage level of the second node with respect to the voltage level of the third node is less than the threshold voltage level, the third node outputs a second control signal different from the first control signal.
A photocontrol apparatus to permit, when in an electrically continuous state, a source of electrical power to provide a power signal to an input of a control device used to control the delivery of power to a load device, the apparatus comprising:
- a switch including a first node, a second node, and third node, the first node electrically, communicably coupled to the source of electrical power and the third node electrically, communicably coupled to the input of the control device;
- and
- a photosensor electrically, communicably coupled between the second node and the third node, the photosensor operable to at least partially cause a voltage level of the second node with respect to the voltage level of the third node to change when the photosensor outputs current in response to being at least partially illuminated with light, wherein
- when the voltage level of the second node with respect to the voltage level of the third node is greater than a threshold voltage level, the photocontrol apparatus outputs the power signal, and
- when the voltage level of the second node with respect to the voltage level of the third node is less than the threshold voltage level, the photocontrol apparatus does not output the power signal.
A photocontrol apparatus comprising:
- a switch including a first node, a second node, and a third node, wherein the first node of the switch is electrically, communicably coupled to a source of electrical power and the third node of the switch is electrically, communicably coupled to an input of a control device;
- a comparator including a first power supply node, a second power supply node, a first input node, a second input node, and a power output node, wherein the power output node is electrically, communicably coupled to the second node of the switch and at least one of the first and the second power supply nodes is electrically, communicably coupled to the third node of the switch;
- and
- a photosensor electrically, communicably coupled between the second node of the switch and the third node of the switch, the photosensor operable to at least partially cause a voltage level of the first input node with respect to the second input node to change when the photosensor outputs current in response to being at least partially illuminated with light.
Dependencies are inferred from the claim text.