By BizLED Bureau
Mar 27, 2017: Making an informed decision about LED systems means knowing what questions to ask your supplier. To help you get started, here is a list of the top 10 questions you should ask your supplier:
1. Is your company registered as a Department of Energy (DOE) Quality Advocate and have you taken the Quality Pledge for Solid State Lighting (SSL) Products?
A company should be registered as a SSL Quality Advocate. It should have a commitment to customers that its LED products perform as claimed and that it will support continuous improvement in SSL product quality.
2. Whose LEDs do you use in your products and have your products gone through an Intellectual Property (IP) clearance?
A company should respect the valid IP rights of others. Its products should go through a rigorous patent clearing process.
3. What is the LED manufacturer’s LED performance rating and what is the rating of your LED system or final product?
A company should not base product performance ratings solely on data from the LED manufacturer. Instead, it should conduct both in-house and independent laboratory tests of the LED, sub-system and complete LED system to determine actual product performance that takes into account thermal, optical and LED driver losses.
4. What precautions do you take to ensure that the LED selected for your product will meet the performance requirements for which it’s rated, and can you share your data showing the LED selection/testing process?
Prior to selecting a LED for its product, the company should perform long-term qualification testing at multiple temperatures and operating currents where it should look for trends in color shift, light output depreciation and power consumption. Then it should compare its test data against the LED manufacturer’s claims to validate performance. If the LED test data meets its minimum standards for performance, the LED may be approved for product use. Upon request, the company should should share its test data with customers.
5. Does your product use LEDs that have been LM80 tested to demonstrate L70 life after 6,000 hours of test, and if yes, can you share your LM80 data and life model that was used to demonstrate the L70 life?
The company should use LEDs that are tested to the LM80 requirements if available. Its LM80 life data should complement its comprehensive in-house testing of the LEDs. The combination of the two tests significantly will increase the confidence level in providing a rated life claim for its LED systems.
Upon request, the company should share LM80 test data with customers if available as not all LED manufacturers currently provide LM80 tested LEDs or are willing to share their test data.
6. Does your LED product meet the LM79 requirements, and if yes, can you provide the LM79 test report from an accredited NVLAP test lab?
When required, the company should test its LED products to LM79 standards and provide the NVLAP report upon request.
7. Do you ‘design in reliability’ or do you just ‘test for reliability’ to demonstrate the long-term performance of your product and can you share your product development reliability process?
The company should follow the GE Six Sigma methodology and use the 10-step Design For Reliability (DFR) process. This allows it to ?design in? a specified level of reliability into its products that takes into account various stress conditions the product will see over its lifetime in a real world application. Its rigorous testing protocol will help it validate that the product will perform as designed over its rated life. Testing is a useful tool to help validate product robustness, but ?design for reliability? helps ensure that the product will perform as expected over time.
Upon request, it should share with customers its design for reliability process.
8. What type of testing do you perform to validate your product life and safe operation and can you share the test results?
To help validate product life, all LED systems must undergo high-temp testing at 140°F for at least 10% of its rated life to show that the product meets or exceeds its life claim. That means a product with a rated life of 50,000 hours will be subjected to a minimum 5,000 ours of continuous testing. In addition, the company should also conduct high-temp, high-humidity accelerated life testing for up to 1,000 hours at 140°F / 90%RH. It should also perform robustness testing to identify the weakest links and to ensure the product will fail in a safe manner.
Upon request, the company should share its test data with customers.
9. What actions take place in the factory to ensure your product will work properly when installed by the customer?
All the products should be manufactured in strict accordance to a detailed set of assembly instructions that include incoming component inspection/testing and multiple production line quality checks to help ensure that the final product is built to its exacting standards.
10. How do you ensure the product will continue to meet the specification?
To help ensure long-term performance, the company should continue to test LED products for years after initial launch. At predefined intervals, it should pull samples out of production and send to its NVLAP certified facility for LM79 testing.
Source: GE Lighting