“The thermal environment near the LED is altered by both the luminaire design and the application environment. By measuring the performance characteristics at various temperatures the luminaire manufacturer can model the expected light output of a given luminaire design, including those for decorative lighting and non-directional applications,” said Rita Harrold, director of technology at the IESNA.
The new standard references LM-79 for all photometric and electrical measurements, but with the measurements performed at elevated temperatures. Therefore, LM-82 can be viewed as essentially the LM-79 standard procedures, but with that characterization extended to include any performance degradation of LED light engines and integral lamps that might occur at elevated temperatures. The LM-82-12 publication is available at the IES website for $25 for non-members and $17.50 for IESNA members.
An LED light engine is defined as “an integrated assembly comprised of LED packages (components) or LED arrays (modules), LED driver, and other optical, thermal, mechanical and electrical components,” according to the ANSI/IES RP-16-2010 standard. The definition continues “The device is intended to connect directly to the branch circuit through a custom connector compatible with the LED luminaire for which it was designed and does not use an ANSI standard base."
The same standard defines an integral LED lamp as "an integrated assembly comprised of LED packages (components) or LED arrays (modules), LED driver, ANSI standard base and other optical, thermal, mechanical and electrical components. The device is intended to connect directly to the branch circuit through a corresponding ANSI standard lamp-holder (socket)."
IES LM-82 outlines the measurement procedures for the luminous flux of LED light engines and integral lamps using AC power sources, unless the device is designed specifically for direct current.
