Do LED Lights offer a high life time of 50,000 Hrs as in manufacturer's catalogs? There are some factors causing LED Luminaries ending their life in an unexpected way before the actual life time offered by the manufacturer.
Integral parts of an LED lights are LED chip, LED Driver, and Heat Sink (which is generally LED fixture body), wires and harness.Another important material is the thermal compound which is applied as an interfacing material between LED chip thermal exchange pad and heat sink.
There are certain criteria in selecting above components and integrating them to a product resulting in a high performance and highly reliable product.
Why do LED luminaries fail early
Power supply variations:
LED lights are sensitive to fluctuations and surges in power supply which will cause LED driver failure. The best thing to prevent this to enable surge protection for LED drivers while manufacturing them.Also external surge protection devices can be installed to ensure higher protection. LED drivers also should operate in a wide range of input voltages say 85-320VAc. Before purchasing the LED drivers, read the manufacturer's product manual to ensure that basic protection is enabled.
This is an important factor which should be given proper attention while assembling LED luminaries. Thermal interfacing material used should be adequate to conduct the heat from LED junction to the surface of heat sink so that the junction temperature of the LED chip specified by the manufacturer should be with in the permissible limit. Thermal characteristics of the thermal compound should be inline with the LED chip manufacturer's specifications, following the same will give a good life time. If a manufacturer is failing to use a thermal compound with adequate thermal conductivity, causing early burn out of LED chips so that the luminary life will be drastically lowered.
An adequate hear sink with area of dissipation designed according to the LED chip manufacturer's specification is also mandatory.
Manufacturing: ESD sensitive devices
LEDs are sensitive to electrostatic charges. LED luminaries should be manufactured in ESD proof environments. Proper measures should be provided to handle the luminaries to protect them from static charge this will ensure a high life to luminaries. Improper assembling setups will cause permanent ESD damages to luminaries. Always refer the ESD guidelines before handling LED components.
LED lighting products are gaining popularity among common people these days also the chances of choosing an undesirable product is more than ever. For choosing a desirable product, the following FAQs will be useful.
1. Choose higher lumen: Don't compare the power of the luminaries compare the lumen output. This will help you achieve more performance in same power compared to the luminary having less lumen output, sometimes you can reduce the no. of luminaries also.Different make of LED luminaries having same power may deliver different lumen outputs
2. Efficiency> 85%: LED Driver: choose a driver with higher efficiency. We need at least 85% efficiency to achieve the power savings offered by the LED technology.
Which means a costlier LED luminary with lower efficiency driver may consume the same power of standard fluorescent luminary having higher efficiency driver. How ever higher the efficiency higher will be the cost of the luminary.
3. Power factor>0.9 : Power factor of the LED driver should be greater than 0.9 and THD< 15 to avoid more loading on the electrical grid and on your generators or inverters. With higher power factor you can connect more load to the existing generator or inverter compared to a lower PF one.
Last few years Indian LED market is growing exponentially and LED will hold 80% of the Lighting market share by 2020. Nowadays most of the customers choose LED lighting products for their lighting applications especially home, outdoor, commercial and industrial application.
How will we find best suited LED lighting application. This article will help you to find the application areas and LED fixtures that will give you better savings, performance and better ROI.
Following application areas to be chosen for achieving maximum advantages from LED lighting
Life of LED
It is calculated that LED chips will give a long life up to 150000 hrs compared to 10,000 hrs of CFL and 1000 Hrs of Incandescent bulbs. But the life of LED s is dependent on the make of LED, thermal management of the LED fixture and LED driver life. If anything of above said is not matching the criteria for good performance of LED chips and according to the specs given by the manufacturer, the LED's life drastically reduce even if it offer a very long life in the datasheets.
Long life of the LED light engines means you don't need to replace a LED light for 17 Years even if you are using it for 24 Hrs a day. So there is no burden of replacing the damaged products and you can save money buying new products for replacing damaged one and also maintenance costs will be very low.
LEDs uses 50-70% less power compared to conventional luminaries. One should be very careful in choosing LED light engines to achieve the above said. Since the LEDs are available offering 30-160 Lm/W, the customer should select atleast 105 Lm/W LED to achieve an equivalent performance of CFLs which offer 60 Lm/W . Since the LEDs are directional and radiating in a narrow beam angle, say 120 Degree it will create more impact on performance compared to conventional fittings which is radiating in 360 Degree where there is a loss caused by the reflector or shade we use integrated with the light engines.
Customers should also choose a good quality driver having higher energy efficiency and power factor, built in with long lasting electronic components to enjoy the max power saving and long life.
Moreover LEDs contains no toxic substances like Mercury which is there in CFLs, disposal of these light engines have a lesser impact on the environment.
Other benefits are
What are the facts we need to focus before purchasing an LED lighting product. In this blog you can read some of the most important lighting facts customers need to know before taking a decision to choose a product.
Do you know that High Bright LEDs offer different lument output for same power? Yes LEDs are available in the market that offer 30-160 Lm/W(Lumen /Watt). Lm/W is commonly reffered to the term Luminous eefficacy.This means that for the same power two LEDs having different efficacies can offer different lumen output.
Customers may not be aware of this fact. Normally LED lighting products in the market are compared on the basis of output power of the product by customers. This may mislead them to choose a product with lowest price comapred to high priced products so that the products choosen may not be delivering sufficient amount of light customer need since the price of the LED lighting products generally depends on light out put of the product.
So it is a good thing to compare price/lumen than price/watt when we decide to purchse a LED lighting product. It is more surprising to know that choosing a product with lowest luminous efficacy wont help you to save electricity considerably like you think, since you need to install more light engines having lowest efficacy compared to a high efficacy product, which in turn will increase your initial investment and power cost. It is a best option to choose a product offering lower price/lumen and higher efficacy.
Key words: Lumen(Lm): Unit to measure light
LED driver efficiency
When calculating luminous efficacy we should consider luminous efficacy also, since the total power consumed by the LED driver considerable vary with the efficiency of LED driver. For example consider a LED driver is having a power output of 8W and with efficiency 90% , total power consumption of the product will be 8+10%=8.8W. Customer should consider this point while choosing a LED lighting product since the drivers are available with efficiency from 7 to 98%, choosing a driver with lower efficiency will lead to higher power charges compared to a driver with high efficiency.
Power factor generally denoted by PF, gives an idea about how effectively a driver utilises the electricity given to its input. PF has an effect on the countrys electric grid. It is a number given between 0 and 1 and it is best to choose a HPF product always. Quality LED drivers are available with a powr factor greater than 0.9.