ANSI/IES LM-80-21

Measuring Maintenance of Light Output Characteristics of Solid-State Light Sources

$60.00

Member Price: $40.00

ANSI/IES LM-80-21
Document Type: Lighting Measurement and Testing (LM)

Available as a downloadable secure PDF only.

To stay current with all IES standards, we recommend subscribing to the The Lighting Library as an Individual or through your company as a Sustaining Member.

In stock

SKU: ANSI/IES LM-80-21 Category: Tag:

Product Description

Approved American National StandardLEDs typically exhibit very long operational life characteristics and, depending on drive current and use conditions, can be in use for 50,000 hours or longer. The light output from LEDs slowly decreases over time. This characteristic of declining output without sudden and permanent failure creates a risk that an LED-based lighting product near end of life may be operating but performing outside the product’s specification, or outside required codes, standard practices, or regulations. LEDs may also undergo gradual shifts in the emitted spectrum over time that may result in unacceptable appearance or color rendering, or degraded efficacy. This document provides the methods for measurement of luminous flux and color maintenance for LED packages, arrays, and modules. It covers luminous, radiant, or photon flux maintenance and color maintenance, including changes in chromaticity coordinates, peak wavelength, or centroid wavelength versus time. The maintenance characteristics are measured under controlled conditions that allow direct comparison of results obtained at different laboratories.

Page count: 15 pages
Publisher: Illuminating Engineering Society (2021)
SKU: ANSI/IES LM-80-21
ISBN-13: 978-0-87995-407-9

Chapters:

  • 1.0 Introduction and Scope
    2.0 Normative References
    3.0 Definitions
    4.0 Physical and Environmental Conditions
    5.0 Electrical Conditions
    6.0 Optical and Electrical Measurement Procedures
    7.0 Maintenance Test Preparation
    8.0 Maintenance Test Procedures
    9.0 Test Report

Citation Format:
Illuminating Engineering Society. ANSI/IES LM-80-21, Approved Method: Measuring Maintenance of Light Output Characteristics of Solid-State Light Sources. New York: IES; 2021.

CONTENTS

  • Foreword
  • 1.0 Introduction and Scope
  • 2.0 Normative References
  • 2.1 ANSI/IES LS-1-20
  • 2.2 ANSI/IES TM-27-20
  • 2.3 ASTM Standard E230/E23M-112
  • 3.0 Definitions
  • 3.1 air temperature (TA)
  • 3.2 centroid wavelength (λc)
  • 3.3 device under test (DUT)
  • 3.4 dominant wavelength (of a color stimulus) (λd)
  • 3.5 drive level
  • 3.6 luminous flux maintenance
  • 3.7 maintenance test
  • 3.8 measurement interval
  • 3.9 optical radiation
  • 3.10 peak wavelength (λp)
  • 3.11 photon flux (Φp)
  • 3.12 photon flux maintenance
  • 3.13 radiant flux (Φe)
  • 3.14 radiant flux maintenance
  • 3.15 temperature measurement point (TMP)
  • 4.0 Physical and Environmental Conditions
  • 4.1 General
  • 4.2 Humidity
  • 4.3 Air Temperature and Air Movement
  • 4.4 Temperature Measurement Equipment or System
  • 5.0 Electrical Conditions
  • 5.1 DUT Drivers
    5.1.1 DC Constant Current Drive
    5.1.2 Pulse Width Modulated (PWM) Current Drive
    5.1.3 DC Constant Voltage Drive
    5.1.4 AC Regulated Voltage Drive
  • 5.2 Drive Level Value
  • 6.0 Optical and Electrical Measurement Procedures
  • 6.1 DUT Optical and Electrical Measurement System and Measurement Method
  • 6.2 Equipment Calibration and Measurement Corrections
  • 6.3 Flux Measurements
  • 6.4 Measurement of Spectrum-Dependent Characteristics
    6.4.1 Chromaticity
    6.4.2 Peak Wavelength
    6.4.3 Dominant Wavelength
    6.4.4 Centroid Wavelength
    6.4.5 Spectral Power Distribution

  • 6.5 DUT Measurement Temperature Condition
  • 6.6 DUT Measurement Drive Level
  • 7.0 Maintenance Test Preparation
  • 7.1 DUT Identification and Tracking
  • 7.2 Seasoning or Aging
  • 7.3 Timekeeping
  • 8.0 Maintenance Test Procedures
  • 8.1 DUT TMP Temperatures
  • 8.2 Maintenance Test Duration and Measurement Interval
  • 8.3 Recording DUT Failures
  • 9.0 Test Report
  • 9.1 Administrative Information
  • 9.2 DUT Identification
  • 9.3 Maintenance Test Conditions
  • 9.4 Test Equipment
  • 9.5 Maintenance Test Duration
  • 9.6 Measurement Intervals
  • 9.7 Failed DUTs
  • 9.8 Working DUTs: Measured Optical and Electrical Results
  • 9.9 Optional Items
  • Annex A – Methods for Monitoring of TMP Temperatures
  • Annex B – Chip-on-Board (COB) Devices
  • Annex C – Additional Laboratory Best Practices
  • Annex D – Additional Reading
  • Informative References