IES LM-79 "Electrical and Photometric Measurements of Solid-State Lighting Products"

As the development of LED technology continues to grow and diversify, the need for consistent and standardized testing procedures for LED has become more prevalent than ever. SHNEZHEN Southern LCS Compliance Testing Laboratory Ltd. is an NIST NVLAP Accredited testing for LM-79 (NVLAP Lab Code: 600167-0).

LCS Testing Laboratory has made strides to stay current with the new testing standard LM-79 set forth by the IESNA (Illuminating Engineering Society of North America). In addition, "IN-SITU" testing is now a priority when testing our LED light systems for more reliable results.

IES LM-79 "Electrical and Photometric Measurements of Solid-State Lighting Products"

Approved method describing procedures and precautions in performing reproducible measurements of LEDs:

• Total luminous flux
• Electrical powers
• Luminous Intensity distribution
• Efficacy (lm/watt)
• Chromaticity

LM-79 Scope

Applies to LED-based products incorporating control electronics and heat sinks, that is, those devices that require only AC mains power or a DC voltage power supply to operate.

Absolute Photometry Basis

• LM-79 requires complete luminaire testing
• Traditionally, photometric evaluation of lighting products is based on separate tests for lamps and luminaires ("relative")
• For SSL products, LED lamps typically cannot be separated from their luminaire because of heat effects ("absolute")

Relative vs. Absolute Photometry

• Relative testing – Lamps of interest and luminaire (with reference lamp) are measured separately. Then the actual light distribution and intensity of the complete luminaire of interest is derived by normalization of the test data
• Absolute testing – The actual light distribution and intensity of the luminaire of interest is measured directly from the complete luminaire.