Register Here | Login | My Account | Shopping Cart | Customer Service | Search| Items in Cart (0) | Quotes (0)
Call 1-800-369-6671
(Military/Intl Sales - 214-616-6180)

Vast Inventory for Fast Shipping. Custom Builds Available, Rentals and Sales.
Most items in stock for fast shipping!! UPS Ship Map Credit cards & Paypal Accepted
Home - Articles You're NOT logged in, Please log in   

Company Information

Product #:

ATEX and IEC Ex Flame-proof Explosion Proof Lighting & Equipment
Explosion Proof Lights
Explosion Proof Motors - Motors for Hazardous Locations
Industrial and Vaporproof Emergency Failsafe Lighting
Industrial Cord Reels and Tool Taps
Industrial Work Area Heaters
Machine Vision Lights
QC Series Industrial Portable Lighting - Quick Change Mount
Rig Lights
Stadium lights
String Lights and Temporary Light Stringers
Tank Cleaning Lights
Three Phase Motor Soft Starters
Vapor Proof LED Lights
Variable Frequency Drives (VFDs)
Vehicle Mounting Plates
Workboat Light Fixtures & Lighting Equipment
Yacht Engine Room Lights
Color Changing LED RGB Lighting
Explosion Proof Cord Reels
GOLIGHT Spotlights
Larson FUTURE - Lease Lighting
Remote Area Lighting and Scene Lights
Utility Bucket Mount, Receiver Hitch & Trailer Mount Lighting
Aevum Control Lighting and Equipment - IIoT
Butane and Solvent Extraction Room Lighting and Equipment
DC to DC Transformers and Power Supplies
Explosion Proof Fans & Blowers
Explosion Proof Paint Spray Booth Approved Lights
Explosion Proof String Lights
Explosion Proof Switchgear & Controls
Fleet Service Lights and Lighting Equipment
Industrial Equipment Trailers
Industrial Handlamps & Droplights
ISO 14644/FS-209E Clean Room Lighting
LED Blasting Lights
Night Time Fishing Lights
Portable AC Power Supply Units
Portable Power Distribution Panels
Power Distribution Panels with KVA Transformers
Self-Contained Lighting
Service Pit Lighting
Solar Generators & Solar Powered Lighting
Agricultural Farm Equipment Lighting & Beacons
Explosion Proof Cameras & Surveillance Systems
Explosion Proof Emergency Lights
Explosion Proof Heaters
Garage & Gas Station Canopy Lights
LED Grow Lights
LED Lights
NDT Ultraviolet Lights
Portable Hazardous Location Lighting
Radio Communication Towers and Equipment
Salt Water Processing Equipment
Shelter & Tent Lighting
Thermal Monitoring Cameras and Systems
48V LED Equipment Lights
ATEX Rated Explosion Proof Lights
Automotive Lighting
Class Rated Signals, Alarms, and Systems
Hazardous Location Area Lights and Portable Lighting
HID Equipment Lights
Hot Work Permit Lighting and Equipment
Hunting Lights
Industrial lasers
Industrial Transformers
Light Towers
Outdoor Lighting
Remote Security and Surveillance Systems
Temporary Construction Lights
Vehicle Mounted Spotlights
Equipment & Heavy Machinery LED Light Package Fitouts
Phase Converters - Single to Three Phase
Marine Shore Power Cords and Equipment
24 Volt Military Lights
Disaster Relief / First Responders / Search & Rescue Lighting
Plastic Handcuff Key
110/120 Volt Flood Lights
Post Mount Spotlights
Magnetic Work Lights
Crank-up Light Masts
Intrinsically Safe Lights
Military Flashlights
LED Waterproof Lanterns
Work Area Lights
12 Volt Flood Lights
Boat Spotlights
New Boat Lights
HID Boat Lights
Boat Dock Lights
Remote Control Lights
Control Lights
Tow Lights
Magnetic Control Lights
NEW Lights and New Products
Evaporative Coolers
Police Equipment
AC/DC Transformers
Power Supplies
Military Spotlights 24V
Infrared Filters, Covert Covers, and Blackout IR Lenses
Military Equipment
Ultralife Batteries
Remote Control Pan Tilt Base
Larson Electronics Spotlights
Larson Electronics Parts
Replacement Lamps
Cords - Brackets
Portable Wheeled Generators
Non-Hazardous Location Extension Cords / Plugs / Outlets
HID Work Lights
HID Dive Lights
HID Off Road Lights
Acro Lights HID Lights
Halogen Lights
Acro Light Flashlight
Xenon HID Flashlights
Powerlight Flashlight
HID Flashlights
Xenon Flashlights
LED Status Lights
Forklift Lights
Tractor Lights
HID Post Mount Lights
Roof Mount Lights
Post Mount Light parts
Flashlight Holder
Magnet Spotlight Base
Tripods-Magnetic Base
Recharging Spotlights
Fire Rescue Lights
LED Street Lights
Utility Lights
Hazard Lights
Strobe Lights - Battery Operated
Strobes & Beacons
Strobe Light Bars
Headlights - Headlamps - Hard Hat Lights
Suction Mount Lights
Magnetic Spotlights
12/24 Volt Spotlights
Gifts For Men
New 12 / 24 Volt Lights
Explosion Proof Accessories and Replacement Parts
Explosion Proof Lighting
Explosion Proof Hand Lamps (Drop Lights)
Explosion Proof Lights - Stand/Dolly
Explosion Proof Tank Lights
Explosion Proof Phones and Intercoms
Explosion Proof Extension Cords
Black Friday & Cyber Monday Specials
Crane Lights
Explosion Proof Light Rentals
General Light Rentals
Light Tower and Light Plant Rentals
Power Distribution Rentals
Power Plant Lighting
Refinery lights
Environmental Services Lights
Aerospace Lights
Chemical Plant Lights
Food Grade Safe Lights
Film and Entertainment Lights
Handheld Meters and Devices
Waste Water Treatment Lights
Mining Lights
Ship Yard Lights
Work Site Lighting

03/15/12 LEDs and Actual LED Lifetime versus Lumen Maintenance

Article- March 2012 By Larson

Larson Electronics General Area-150 Watt High Bay LED Light Fixture

Larson Electronics General Area-150 Watt High Bay LED Light Fixture

Although LEDs are quickly making inroads towards potentially becoming the dominant alternative to incandescent light bulbs, there remain serious obstacles. Perhaps one of the biggest remaining issues concerning LEDs is the lack of a clear and easy to understand standard by which to judge their performance. Since LEDs produce light in wholly different manner from traditional forms of lighting, attempting to apply old methods of measuring things like lamp life and lumen output has proven difficult. Manufacturers and developers of course understand this better than anyone, but as yet there exists no single accepted set of standards or regulations by which all LEDs can be compared and or certified. The result has been a confusing LED lighting landscape, with wide variances in the performance of LEDs from one manufacturer compared to the next.


Standards are voluntary guidelines adhered to by developers and manufacturers in order to ensure homogeny between different versions of the same technologies. Although LEDs offer vast improvements over traditional forms of lighting, and thus are attractive to a wide range of lighting sectors, the lack of homogeny among manufacturers means it is difficult to be certain a particular LED product is going to perform to expectations. Without an accepted set of standards to which all developers adhere, there is no way to really be certain that an LED product is going to perform as advertised or to customer expectations.





One of the bigger areas of confusion for consumers and commercial applications is the manner in which LED longevity and output are measured. We often see LEDs advertised as having a “50,000 hour lifespan”, but what does this really mean? For most people, the natural assumption would be that after 50,000 hours, the LED can be expected to soon fail to produce light, in essence, burn out much like a traditional incandescent lamp does at the end of its life cycle. However, this is not exactly the case, and the manner in which actual LED life is measured takes into account not only the expected time of failure, but average lumen maintenance over the life of the LED fixture. As a result, we often see LEDs advertised as having 70% lumen retention after 50,000 hours.




The confusion here is between actual LED life expectancy and LED lumen maintenance. The rated life span of a typical luminaire is defined in ANSI/IES RP-16, as “the life value assigned to a particular type lamp. This is commonly a statistically-determined estimate of median operational life.” What this means is, that for a given sample number of lamps, the percentage of those which fail at certain intervals will determine average lamp life. Rated life is thus a statistical measure and is defined as “Bp”, with p denoting the percentage. If a sampling section achieves a B50 rating at 1,000 hours, it means that half the tested samples operated for 1,000 hours without any failures. In traditional lamps, life is typically measured by the amount of time it takes for 50% of a sample group to actually fail.



LED light fixtures are different from typical incandescent lamps though because they do not tend to simply fail to produce light although this will eventually occur. They can continue to operate far past their actual useful life, which makes understanding the difference between rated life and lumen maintenance critical. Unlike rated life, lumen maintenance denotes the percentage of light produced at a given period of operating time versus initial lumen output. This is important because although an LED may appear to be operating normally after a given period of time, its actual lumen output may have decreased significantly. This is a similar problem encountered with HID lighting, wherein color shifting and reduced output occurs over the life of the lamp. However, with HID lighting, the lumen depreciation is more pronounced, and operating performance also degrades significantly as well with the typical slow starting and on/off cycling associated with HIDs that have reached the end of their useful life becoming pronounced. LEDs thus have a useful life that is better understood as the amount of time before a certain percentage of lumen loss occurs. The problem is that manufacturers and marketing sometimes adhere to the more impressive numbers generated regardless of their origin. You may see an LED advertised as having a 100,000 hours life span rating, but in reality that LED is only producing 40-50% of its original output by that time.


The lack of standardization does not allow an expectation of practical uniformity among LED designs that can be applied on a wide scale. Some of the more reputable manufacturers include lumen maintenance figures along with an expected life rating, which helps a great deal in determining LED suitability for a given task, but this is currently not the norm. Industry groups have been attempting to devise a set of standards and guidelines to address these problems, but the complexity of LED operation makes this a difficult task to say the least. Unlike traditional forms of lighting, LEDs require additional hardware in the form of voltage regulating circuits and heat management in order to operate reliably. They cannot operate natively with normal AC voltages encountered in common applications, and thus require additional drivers to convert and reduce voltage to the low levels they require. The actual performance of an LED is greatly dependent upon such LED driver hardware, and thus this must also be included within the quest for standardization. In some testing, it has been noted that actual operating life was determined more by the failure of LED drivers than the actual failure of the LEDs themselves.


Currently, industry experts are suggesting the use of combined data from both lumen maintenance and actual failure percentages to produce a realistic and effective overall LED lifetime average. This would likely be the most effective route to standardization, but requires addressing not only LEDs but the technology used to power them as well. Until a set of standards is devised, it is likely we will continue to see irregularities among manufacturers and the resultant reluctance on the part of many lighting professionals to utilize LEDs in new designs due to an inability to form practical expected performance parameters. In the meantime, it is probably best for most consumers to use average lumen maintenance figures when evaluating LEDs as this method offers the best way to measure expected LED lifetime performance.



Related Categories/Products
Category/Product (click on link below for more information)
Explosion Proof Lights
Explosion Proof LED Hand Lamps
Intrinsically Safe Dual Lamp Headlamp - Five Mode Class 1 Division 1 Headlight - Spot/Flood Beam
Explosion Proof LED Drop Light / Trouble Light -10 Watt LED - 120-277V AC - 100 Foot SOOW Cord
Explosion Proof Ventilation Duct Coupling
Aluminum Coupler for Explosion Proof Ventilation Fan Ducts
Explosion Proof LED Aluminum Drop Light - Class 1 Div 1 - 100' Cord
Explosion Proof, 15 Watt LED Tube Drop Light - Class I, Div. I - 50' SOOW Cord w/ Exp. Proof Plug
Explosion Proof LED Light - 17,500 Lumens - Class 1 Div 1 & Class 2 Div 1 - Adustable J-Bracket
Class I, Div. I Explosion Proof Fixture- IP67
Home | Contact Us | Return Policy | Privacy Policy | Security Policy | Copyright © 2006-2018. All Rights Reserved.