Brightness monitoring for led failures and daylighting target adjusting

Abstract

A system monitors operational status of a lighting element. A lighting fixture processor instructs a lighting element to illuminate at a predetermined time, receives sensed light level information from the light sensing element, and transmits a wireless message including information representing the sensed light level. A room controller can control some or all of these steps. A daylighting arrangement includes a room controller that instructs the lighting fixtures of a lighting group to illuminate their lighting elements at a predetermined time of day. Sensed light level information is obtained and wirelessly transmitted to the room controller, which determines an initial daylighting target for the lighting fixture group based on an average of the sensed light level information. The room controller instructs the lighting fixtures to illuminate their respective lighting elements in accordance with the initial daylighting target.

What is claimed is: 
     
         1 . A system for monitoring operational status of a lighting element, comprising:
 a lighting fixture including a housing, a lighting element and a lighting fixture transceiver, the lighting element and the lighting fixture transceiver disposed within the housing;   a light sensing element; and   a processor communicatively coupled to the lighting fixture and the light sensing element;   wherein the processor is programmed to:
 instruct the lighting element to illuminate at a predetermined time; 
 receive sensed light level information, said sensed light level information representing information obtained by the light sensing element while the lighting element is illuminated, said sensed light level information comprising a sensed light level value; 
 compare the sensed light level value to a predetermined light level value and; 
 transmit an alert when the sensed light level value deviates from the predetermined light level value by a predetermined amount. 
   
     
     
         2 . The system of  claim 1 , wherein the light sensing element is disposed in the lighting fixture housing. 
     
     
         3 . The system of  claim 1 , wherein the light sensing element is disposed within a room in which the lighting fixture is disposed, the light sensing element positioned to receive light from the lighting element of said lighting fixture, and also to receive light from an additional lighting element of at least one additional lighting fixture disposed within the room. 
     
     
         4 . The system of  claim 1 , wherein the predetermined time is at night so as to minimize a contribution of natural light to the sensed light level information. 
     
     
         5 . The system of  claim 1 , wherein the processor comprises a lighting fixture processor disposed in the lighting fixture housing. 
     
     
         6 . The system of  claim 1 , wherein the alert is transmitted via the lighting fixture transceiver. 
     
     
         7 . The system of  claim 1 , wherein the alert is a wireless message transmitted via the lighting fixture transceiver. 
     
     
         8 . The system of  claim 7 , wherein the processor comprises a first processor of a room controller. 
     
     
         9 . The system of  claim 8 , wherein the room controller comprises a second transceiver for wirelessly transmitting the alert to the remote device. 
     
     
         10 . The system of  claim 9 , wherein the wireless message includes information identifying the lighting fixture that transmitted the wireless message. 
     
     
         11 . The system of  claim 1 , wherein the predetermined light level value comprises an initial illumination value for the lighting fixture. 
     
     
         12 . The system of  claim 11 , wherein the predetermined amount comprises a percentage value less than the initial illumination value for the lighting fixture, wherein the percentage value is based on the initial illumination value. 
     
     
         13 . The system of  claim 1 , wherein the (i) instruct, (ii) receive and (iii) transmit steps are performed periodically at the predetermined time based on clock information associated with the system. 
     
     
         14 . The system of  claim 1 , wherein the lighting element comprises a plurality of individual light emitting diode (LED) elements. 
     
     
         15 . A method for monitoring operational status of a lighting element of a lighting fixture, comprising:
 instructing, from a processor, a lighting element to illuminate at a predetermined time;   receiving, at the processor, sensed light level information, said sensed light level information representing information obtained by the light sensing element while the lighting element is illuminated, said sensed light level information comprising a sensed light level value;   comparing the sensed light level value to a predetermined light level value; and   transmitting an alert when the sensed light level value deviates from the predetermined light level value by a predetermined amount.   
     
     
         16 . The method of  claim 15 , wherein the predetermined light level value is an initial light level value of the lighting element obtained by the light sensing element and stored in memory. 
     
     
         17 . The method of  claim 15 , wherein the processor is one of (i) a light fixture processor and (ii) a first processor of a room controller. 
     
     
         18 . The method of  claim 15 , wherein the instructing, receiving and transmitting steps are performed periodically at the predetermined time. 
     
     
         19 . The method of  claim 17 , wherein the predetermined time is at night so as to minimize a contribution of natural light to the sensed light level information. 
     
     
         20 . The method of  claim 15 , wherein the receiving and comparing steps are performed by a lighting fixture processor, and the transmitting step is performed by a lighting fixture transceiver. 
     
     
         21 . The method of  claim 15 , wherein the receiving and comparing steps are performed by a first processor of a room controller, and the transmitting step is performed by a transceiver of the room controller. 
     
     
         22 . The method of  claim 15 , wherein transmitting the alert comprises at least one of (i) flashing an indicator associated with the lighting fixture, and (ii) transmitting a wireless message via a transceiver associated with at least one of the lighting fixture and a room controller. 
     
     
         23 . The method of  claim 15 , wherein transmitting the alert includes transmitting information identifying the lighting fixture to which the alert applies. 
     
     
         24 . The method of  claim 15 , wherein the predetermined light level value comprises an initial illumination value for the lighting fixture. 
     
     
         25 . The method of  claim 24 , wherein the predetermined amount comprises a percentage value less than the initial illumination value for the lighting fixture, wherein the percentage value is based on the initial illumination value.