Vektrex offers complete LM-80 test solutions that meet all IESNA and Energy Star testing criteria. Vektrex actively participates on the LM-80 committee, chairing the LM-80 working group moving this standard through the acceptance process and into IEEE acceptance.
High-capacity Vektrex LM-80 Systems combine spike-protected, constant or pulsed current LED drive electronics with fully integrated thermal control systems and automated light measurement. Vektrex LM-80 Systems are optimized for LM-80-08 and LM-80-15 compliance testing for low, mid and high power LEDs, modules, COBs, and arrays operating in infrared, visible, or UV. Vektrex LM-80 Systems are also applicable for use with laser diodes.
Industry-Leading Drive Electronics
Energy-efficient Vektrex SpikeSafe™ Series current sources supply DC and precision-pulsed drive current up to 50A at voltages up to 400V for LM-80 testing and high-power LED reliability stress applications. Multiple-source channel modules deliver high capacity and high power density with the testing flexibility of independent channel control. SpikeSafe™ load protection continuously monitors voltage and current on all source channels and instantly shuts down when device anomalies are detected. Rapid shutdown preserves the failure device for analysis, protects other devices, reduces failure counts, and improves reliability results.
High-Capacity Thermal Control
Temperature uniformity is essential to successful LM-80 testing. Vektrex Integrated Thermal Control Systems (ITCS) use plant chill water and a closed loop system for uniform thermal control in a compact, energy-efficient footprint. With up to 10kW of power handling capability – at operating temperatures up to 150C – the Vektrex ITCS provides the capacity to test numerous high power devices in a single chamber. Integrated fixturing with convenient slide-out drawers simplify loading and unloading. Available individual drawer temperature controls allow side-by-side testing of multiple device types with different thermal characteristics.
Repeatable Light Measurement
The Vektrex Automated Light Measurement System integrates thermal control and precise electrical and optical instrumentation with easy-to-use software tools for measuring and recording LM-80 photometric and electrical test results. Single pulse, DC and continuous pulse modes are compliant with LM-85 requirements for repeatable high power LED light measurement. With 0.05% flux repeatability, the Vektrex Automated Light Measurement System can detect LED test trends within hours.
Comprehensive Test Software
Vektrex software applications are designed to address and support a wide range of testing needs. The LM-80 software suite includes STARS testing and monitoring software that controls and monitor source channels, loads, and thermal control devices during testing. STARPLOT software application graphically presents a view of reliability data generated by STARS. STARPLOT provides a graphical view of reliability data where defects such as internal shorts in LED arrays, connector wear, and even thermal problems may be identified. From plotting data and identifying trends to failsafe protection and remote thermal control, Vektrex software simplifies test control and accurate data collection.
Whether you’re expanding existing test capacity, or stepping up to higher-power LM-80 LED testing systems, Vektrex systems and components give you the flexibility to scale a wide range of LED testing configurations. Leading manufacturers and LM-80 labs worldwide rely on Vektrex systems and components for unmatched power, capacity, and reliable performance.
|Key LM-80 Requirements||Vektrex Exceeds the Requirements|
|Constant Current Drive (DC Mode)|
PWM Drive / Pulsed
Current Accuracy < 3%
|SpikeSafe™ Protected Modular
Current Sources, available to 400V, 50A
DC and Precision Pulsing
Individual Source Channel Control
Typical Current Accuracy 0.1%
MTBF 175,000 Hours
|Accurate Time Keeping|
Typically 6,000 – 10,000 Hours Duration
DUT Failure Recording
|Logs Data, Monitors Errors & Faults,
Duration Timers, Data Visualization
|Two or More Test Temperatures|
-2 to ∞ Case Temperature Control
-5 to ∞ Air Temperature Control
|to 150C Operation, 0.2C Stability,
up to 10kW / Chamber Load
UV, IR, VIS, & Array Device Support
Selectable Measurement Temperature
|Automatically Tests up to 80 DUTs
Repeatable to 0.05% Flux Measurement
|Test Timing Uncertainty Analysis||Numerous NVLAP Certified Installations
- Working group tasked to add laser diodes and filament LED lamps to the LM-80 standard.
- Jeff Hulett, Vektrex, chairs their working group.
- Scope expanded to include radiant, photon or luminous flux maintenance
- Air temperature control required (shall)
- Alternate temperature sensor acceptable (RTD, Thermocouple, Thermistor)
- Case temperature taken at manufacturers designated measurement point
- Any light measurement temperature may be used
- Specific methods for monitoring case temperature
- All DUTs shall be tracked
- No seasoning or aging prior to test
- Drive types expanded to include PWM, AC Regulated Voltage, Constant Voltage
- Eliminate ripple and total harmonic distortion requirements
LM-80-08 Addendum (2012)
- Test temperatures reduced to two, one of which must be 55C or 85C
- Different currents may be used at the different test temperatures
- Interpolation per TM-21 to predict luminous flux maintenance requires the same drive current for the two temperatures
- Testing at three or more temperatures offers more accurate interpolations
Key LM-80-08 (2008)/Energy Star Testing Requirements;
- Minimum 20 device test lot per device family
- Minimum 10 device test lot for modules
- Constant Current (DC mode) only
- Current accuracy better than 3%
- Three Test Temperatures: 55C, 85C, and one other selected by the manufacturer
- Thermocouples MUST be used for temperature measurement (special limits wire)
- Case temperature shall be maintained at a temperature greater than or equal to 2C below the test temperature
- Air temperature should be maintained at a temperature greater than or equal to 5C below the test temperature
- Minimum 6,000 hours test time (10,000 recommended)
- Light Measurements collected at T0 and generally every 1,000 hours.
- Light Measurements taken at 25C.
- Test Timing Uncertainty for the software application must be calculated to ensure minimum testing is achieved
- RH less than 65%
- Record Lumen Maintenance, Chromaticity, and Catastrophic failures
- 17025 Lab Certification
- NVLAP Self Certification and LM-80 audit
The LM-80 standard is accepted worldwide. The intent is for LEDs and LED devices to be tested in several standardized operating conditions. The data resulting from LM-80 measurements are matrices of lumen maintenance values. LM-80 defines a standardized report output for the data.
LED manufacturers use this data to predict the LED light output over the life, improve their processes, and compare their devices with other competitor devices. Users of LEDs (for example Lighting Designers) use this standardized data to select the appropriate LEDs for their application and, in conjunction with TM21, to correctly define the warranty period. In the USA, LM-80 testing is required for Energy Star Certification.