NEMA Publishes LED Chromaticity Specs
The National Electrical Manufacturers Association (NEMA) has published ANSI ANSLG C38.377 Specifications for the Chromaticity of Solid State Lighting Products. This publication specifies the range of chromaticities recommended for general lighting with solid state lighting (SSL) products and ensures that the white light chromaticities of the products can be communicated to consumers. This vital information applies to chromaticity standards and definitions and specifications of the color rendering index.
C78.377 applies to LED-based SSL products with control electronics and heat sinks with AC main power or DC voltage power. It covers fixtures incorporating light sources and integrated LED lamps for general indoor lighting applications.
The standard has been arranged in two parts. Part one part includes information on the chromaticity specification basis, explanation of a nominal CCT and target CCT, details of SSL chromaticity requirements, and definition and specification of color rendering index.
Part two comprises a large informative annex, which provides some background information and the technical context in which this chromaticity specification for the SSL products was developed. The annex includes tabled information on the chromaticity coordinates of the center points, and the four corners of each quadrangle for convenience of plotting these quadrangles. The annex also includes three graphical representations split into two figures of the chromaticity specification of SSL products in the tabled information on the CIE (x,y) chromaticity diagram and the (u’,v’) chromaticity diagram. It also includes an example of chromaticity tolerance.
A hard or electronic copy may be purchased for $84 by visiting www.nema.org/stds/ANSI-ANSLG-C78-377.cfm.
NEMA is the association of electrical equipment and medical imaging manufacturers, founded in 1926 and headquartered in Arlington, Virginia. Its member companies manufacture a diverse set of products including power transmission and distribution equipment, lighting systems, factory automation and control systems, and medical diagnostic imaging systems. Worldwide annual sales of NEMA-scope products exceed $120 billion.