Yes, DLC requires a written warranty, but it cannot ensure that the manufacturer stays in business or will honor the warranty. There are many instances of customers going to register warranty complaints and discovering that the company does not exist anymore. Isn’t my warranty proof of product quality? Current “tests to fail” rather than “testing to pass,” which is the philosophy of doing only the minimum necessary to pass industry requirements. Current’s stress testing involves burning at elevated temperatures, high humidity testing, thermal shock (rapid cooling and heating) and more. The amount of thermal heat sinking provided by the manufacturer is critical in determining LED performance over time. LED performance over time is very dependent on temperature. Most LED tube manufacturers do no testing on the chips they purchase, simply accepting the data sheets provided with those chips. In recent years, based on its own stringent requirements, Current has been qualifying only about one-third of the chips it tests without any restrictions, and another third with some form of restriction. Current will reject chips based on light output, color shift and light depreciation. Manufacturers must also provide a written 5-year warranty, but the warranty does not need to be backed by any actual life testing or data on lamp life.ĭoes Current perform its own LED chip testing?Ĭurrent does its own reliability testing, stress testing and life testing of the chips prior to qualifying them for use in its products. DLC also requires that manufacturers submit the LM-80 document for the chips used and measure the temperature of the hottest chip in the lamp for TM-21 predictions. Driver life depends on power quality and the presence of voltage transients in the building where the tubes are used-and the quality of surge protection built in for the drivers, which varies among manufacturers.Īren’t there industry groups like DLC that assure the customer of product quality?ĭLC, or Design Lights Consortium, lists products that satisfy certain criteria like initial lumens, LPW and beam distribution. This is unlike many manufacturers who do no driver testing at all. Current also qualifies its driver components at elevated temperatures, subjecting them to stress testing to ensure a margin of comfort. Current spends resources on its rigorous driver component testing program and selects high-quality components because of the awareness that a tube is only as good as its weakest link. Some LED makers use the cheapest driver available without much testing. That is the life of the LED chips what about driver failures?Įxactly! The life-limiting mechanism today is generally driver failure, not chip failure. Current also has a value offering of certain tubes that are now rated to 50,000 hours. ![]() Current is one of the first to increase the life rating of many tubes to 70,000 hours, based on confidence in the design. Many LED tubes are routinely rated at 50,000 hours. The correctness of a rating is a function of how robust the product is, how much margin there is in design, etc. It is important to distinguish between the life rating of a product and the actual life a typical user will experience. There are many more factors involved in lamp life. L-70 is not a product life-rating-just a projected lumen degradation on the chip. Unfortunately, most people in the industry do not seem to be adhering to this distinction. However, a projection is different from a reported life, and you can project whatever you want with the tool-50,000 hours, 100,000 hours-but you cannot “report” it as life. If the chips have been burned 6,000 hours, you can “report” L70 as >36,000 hours. ![]() TM-21 forecasts the L-70 point, but TM-21 also asserts that L-70 claim is only valid for six times the test duration for the chips. On what basis are they predicting a life-rating? Most claims are projections based on chip testing carried out on the raw LED chips, not on the finished lamp. There is no actual lamp testing (long-term burning) required for the LED tube manufacturer to make life claims. TM-21 is a mathematical curve-fitting model that extends the 6,000-hour data to predict when the LED will go down to 70% of its lumen rating (L70). All LED chips on the market come with LM-80 test data. LM-80 is 6,000-hour testing (minimum) that the LED chip maker carries out. It is difficult for the customer to judge the quality of the LED tubes being offered since they all often look the same, especially in the beginning.īut the company says they are LM-80 and TM-21 tested. Only in that they are all 4 feet long, otherwise there are many differences.
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