SOLID-STATE LIGHTING MEASUREMENT ASSURANCE PROGRAM SUMMARY WITH ANALYSIS OF METADATA

The National Institute of Standards and Technology (NIST) began to offer proficiency testing for Solid-State Lighting (SSL) products through a Measurement Assurance Program (MAP) in 2010. This article communicates the results of the first version of the MAP in which 118 worldwide laboratories participated. Statistical analysis of how the laboratories’ measurements compared to NIST’s measurements are presented. In general, all the laboratory results are within +/- 4 % for total luminous flux and luminous efficacy measurements. The discussion provides reasons for any discrepancies or large uncertainty intervals found in the data. A major finding was that measurement differences of RMS current had a larger standard deviation and number of outliers than expected. Two possible explanations are (1) the discrepancies are due to issues with using 4-pole sockets, and (2) the large deviation is caused by some solid state lamps being sensitive to impedance and slew rate of AC power supplies.