Understanding Lighting - FAQ

Understanding Lighting

LED and Light fixture
What are the factors to consider when choosing a LED fixture?1. Wattage 2. Lumens output 3. Driver configuration 4. Material of the fixture and Heat dissipation
Why is the lumens output of a LED fixture important?The starting point of any lighting is understanding the brightnes level necessary in the environment. The lumens output of the LED fixture determines the brightness; not merely the wattage. Lighting consultants generally define that they want 300lux on the table top. Accordingly, the manufacturer can suggest an appropriate lighting fixture. Also remember that, just deriving a higher lumens output per watt, if overdriven, can be harmful to the life of the LED light fixture.
Why you shouldn't buy a LED fixture just because it has a greater lumens output per watt?Most manufacturers overdrive the LED light (meaning that they drive the LED beyond its most stable operating region) to obtain a higher light output. They do this as this saves them input costs and they have to use fewer LED chips to achieve the given output. Always ask your manufacturer how the LEDs have been biased and take a look a the LED report. Look at the best operating region for a given LED chip and the corresponding fixture design; the two should match. Check if the LED has been overdriven or driven correctly. If the LED has been overdriven, instead of lasting for 10 years, your LED could burn out in 3 years.
How does a diffusing cover affect my LED light fixture's brightness output?A milky while LED ightt diffuser can reduce the lumens output by upto 30% as compared to the naked fixture. A plain, clear acrylic diffuser can decrease the light output by over 20%.
So, should we use a diffuser? The answer depends on individual preferences. For example, Showrooms and Restaurants have begun using Downlights without diffusers to achieve maximum light output for a particular wattage thus cutting their bills. Other Showrroms continue to use diffusers.
What effect does a lens have on a LED light fixture like a track light?A properly designed lens can help either increase the throw of the light or achieve greater focus at a higher lumens output, as the application demands.
Should you be using a lens?The answer depends on the lighting area and the item being focused. You can talk to our lighting consultant in case there are doubts as to how to proceed lighting a certain area.
What is a LED driver and why is it important?The LED driver is the heart of the LED fixture. It manipulates the input AC voltage and current and drives the LED fixture. The life and longevity of the LED ficture, more often than not, depends on the design of the LED driver. There are many types of LED drivers. It can be: a) A Constant Voltage (CV) driver b) A Constant Current (CC) driver A Constant Current (CC) configuration driver is generally used In terms of protection, it can be: a) Online (Non-Isolated) driver b) Offline (Isolated) driver
What is the difference between an isolated and a non-isolated driver?An isolated driver uses a transformer in its design to physically isolate the input and the output sections of the driver. This isolation becomes immensely critical when there are faults in the power system (which happens a lot with the Indian Power Distribution System). The isolation helps in reducing the impact of such faults on the LED fixture, thus protecting the LED fixture from the vagaries of the Distribution system. Remember that using an Isolated driver is still not failproof. In case of big surges, the LED fixtures will still be susceptible to failure. However, compared to a non-isolated driver, an isolated driver is a far better option. An isolated driver is a costlier than a non-isolated driver. If cost permits, always use an isolated driver. A non-isolated driver can also be made robust with certain design considerations. Talk to our technical experts to know how ELectron Lighting achieves greater protection even in the case of non-isolated drivers.
What should I look for in a driver when I buy a LED fixture?Each type of LED driver has its own advantages. The best LED driver depends on a particular situation. But for most general lighting purposes, there is a broad consensus that COnstant Current (CC) drivers are better. Using a Constant Current (CC), Isolated (Offline) driver is the best choice of driver. Certain additional protections can be incorporated in the design of Isolated (Offline) drivers as well to increase their robustness and life. . Talk to our technical experts to know how ELectron Lighting achieves even greater protection in the case of Isolated drivers.
What is the typical warranty on a LED driver?The typical warranty on a LED driver is 2 years.
Heat Dissipation
How critical is temperature regulation to the life of a LED fixture?The life of a LED lighting fixture is dependent on how well it dissipates its heat and maintains an optimum operating temperature. Generally, a temperature less than 50 C is desirable although LED chips can function in excess oof 80 C and even upto 105 C for very short durations. At lower temperautes, between 25 - 35 C, the LED fixture is at its most efficient. This is the optimum temperature range for a LED fixture to work.
What should an artchitect or consultant look at while procuring LED fixture vis-a-vis heating characteristics?More often than not, the heat dissipation characteristics of a LED fixture is not taken into account while procuring. Many architects choose to go for an aesthetic looking fixture instead of a functional one. An ideal LED fixture has to be, both, functional and aesthetic to look at. The functional aspect, for ex, the driver configuration, the material of the fixture needs to be given greater importance. Aluminium is one of the best dissipators of heat and is very light. It is generally desirable to have aluminum fixtures and reflectors.