METHOD OF CONTROLLING SERIALLY-CONNECTED LIGHTING DEVICES
A lighting device may include an elongated housing that defines a cavity. The lighting device may include plurality of emitter printed circuit boards configured to be received within the cavity. Each of the plurality of emitter printed circuit boards may include a plurality of emitter modules mounted thereto. Each of the plurality of emitter printed circuit boards may include a control circuit configured to control the plurality of emitter modules mounted to the respective emitter printed circuit board based on receipt of one or more messages. The lighting device may include a total internal reflection lens for each of the plurality of emitter printed circuit boards. The total internal reflection lens may be configured to diffuse light emitted by the emitter modules of the plurality of emitter printed circuit boards.
1 . A fixture controller comprising:
a power converter circuit configured to generate a bus voltage on a power bus, wherein the power bus is coupled between the fixture controller and one or more lighting devices; and
a control circuit configured to control the one or more lighting devices, the control circuit configured to:
determine a magnitude of the bus voltage on the power bus;
determine that the magnitude of the bus voltage on the power bus is indicative of a brownout event on the power bus; and
send, in response to the determination that the magnitude of the bus voltage is indicative of the brownout event on the power bus, a power message to the one or more lighting devices that instructs the one or more lighting devices to decrease their respective high-end intensity level.
2 . The fixture controller of claim 1 , wherein, in order to determine that the magnitude of the bus voltage on the power bus is indicative of the brownout event on the power bus, the control circuit is configured to:
determine that the magnitude of the bus voltage on the power bus drops below a first threshold voltage.
3 . The fixture controller of claim 2 , wherein, in order to determine that the magnitude of the bus voltage on the power bus is indicative of the brownout event on the power bus, the control circuit is configured to:
determine that the magnitude of the bus voltage on the power bus drops below the first threshold voltage and subsequently rises above a second threshold voltage a predetermined number of times within a predetermined time period.
4 . The fixture controller of claim 3 , wherein, in order to determine that the magnitude of the bus voltage on the power bus is indicative of the brownout event on the power bus, the control circuit is further configured to:
determine that a magnitude of an alternating-current (AC) mains line voltage is stable during the predetermined time period.
5 . The fixture controller of claim 3 , wherein the power converter circuit is configured to control the magnitude of the bus voltage to cause the one or more lighting devices to cease illuminating light when the magnitude of the bus voltage on the power bus drops below the first threshold voltage, and configured to control the magnitude of the bus voltage to cause the one or more lighting devices to illuminate light when the magnitude of the bus voltage on the power bus drops rises above the first threshold voltage.
6 . The fixture controller of claim 1 , wherein the control circuit is further configured to:
cause the one or more lighting devices to turn off in response to a detection of a brownout event.
7 . The fixture controller of claim 1 , wherein the control circuit is further configured to:
cause the power converter circuit to shut down, thereby causing the bus voltage on the power bus to drop to zero volts, in response to a detection of the brownout event, wherein the brownout event is an overload event.
8 . The fixture controller of claim 1 , wherein, in response to a detection of the brownout event and prior to sending the power message, the control circuit is configured to:
send a hold signal to the one or more lighting devices that instructs the one or more lighting devices to wait a predetermined amount of time before turning back on.
9 . The fixture controller of claim 1 , wherein the control circuit is configured to:
send a clear message to the one or more lighting devices that instructs the one or more lighting devices to clear a flag after the control circuit sends the power message.
10 . A method comprising:
determining a magnitude of a bus voltage on a power bus, wherein the power bus is coupled between a fixture controller and one or more lighting devices;
determining that the magnitude of the bus voltage on the power bus is indicative of a brownout event on the power bus; and
sending, in response to the determination that the magnitude of the bus voltage is indicative of the brownout event on the power bus, a power message to the one or more lighting devices that instructs the one or more lighting devices to decrease their respective high-end intensity level.
11 . The method of claim 10 , wherein, to determine that the magnitude of the bus voltage on the power bus is indicative of the brownout event on the power bus, the method comprises:
determining that the magnitude of the bus voltage on the power bus drops below a first threshold voltage.
12 . The method of claim 11 , wherein, to determine that the magnitude of the bus voltage on the power bus is indicative of the brownout event on the power bus, the method comprises:
determining that the magnitude of the bus voltage on the power bus drops below the first threshold voltage and subsequently rises above a second threshold voltage a predetermined number of times within a predetermined time period.
13 . The method of claim 12 , wherein, to determine that the magnitude of the bus voltage on the power bus is indicative of the brownout event on the power bus, the method comprises:
determining that a magnitude of an alternating-current (AC) mains line voltage is stable during the predetermined time period.
14 . The method of claim 10 , further comprising:
causing the one or more lighting devices to turn off in response to a detection of a brownout event.
15 . The method of claim 10 , further comprising:
causing a power converter circuit of the fixture controller to shut down, thereby causing the bus voltage on the power bus to drop to zero volts, in response to a detection of the brownout event, wherein the brownout event is an overload event.
16 . A non-transitory computer-readable storage medium comprising executable instructions that, when executed by a control circuit of a device, cause the control circuit to:
determine a magnitude of a bus voltage on a power bus, wherein the power bus is coupled between a fixture controller and one or more lighting devices;
determine that the magnitude of the bus voltage on the power bus is indicative of a brownout event on the power bus; and
send, in response to the determination that the magnitude of the bus voltage is indicative of the brownout event on the power bus, a power message to the one or more lighting devices that instructs the one or more lighting devices to decrease their respective high-end intensity level.
17 . The non-transitory computer-readable storage medium of claim 16 , wherein the non-transitory computer-readable storage medium comprises executable instructions that, when executed by a control circuit of a device, cause the control circuit to:
determine that the magnitude of the bus voltage on the power bus drops below a first threshold voltage to determine that the magnitude of the bus voltage on the power bus is indicative of the brownout event on the power bus.
18 . The non-transitory computer-readable storage medium of claim 17 , wherein the non-transitory computer-readable storage medium comprises executable instructions that, when executed by a control circuit of a device, cause the control circuit to:
determine that the magnitude of the bus voltage on the power bus drops below the first threshold voltage and subsequently rises above a second threshold voltage a predetermined number of times within a predetermined time period.
19 . The non-transitory computer-readable storage medium of claim 18 , wherein the non-transitory computer-readable storage medium comprises executable instructions that, when executed by a control circuit of a device, cause the control circuit to:
determine that a magnitude of an alternating-current (AC) mains line voltage is stable during the predetermined time period to determine that the magnitude of the bus voltage on the power bus is indicative of the brownout event on the power bus.
20 . The non-transitory computer-readable storage medium of claim 16 , wherein the non-transitory computer-readable storage medium comprises executable instructions that, when executed by a control circuit of a device, cause the control circuit to:
cause the one or more lighting devices to turn off in response to a detection of a brownout event.