FAQ

What is thermal management and why does it matter?
Heat generated by electronic circuitry must be dissipated to improve reliability and prevent premature failure and degradation of the lamp.A typical lamp will degrade significantly for every increase of 10 degrees Celsius, and this applies to all lamp technologies. In ceilings, temperatures can rise to 65 degrees. The best performing lamps will have a well-balanced combination of driver, chip and heat sink, which will provide the most consistent light level and colour over the longest lifespan.

What is efficacy?
Efficacy or luminous efficacy is a term used to describe the efficiency of a lamp, which is measured in lumens per watt (LPW). To determine the efficacy of a lamp, divide the lumen output of the lamp by the watts consumed.
What are the advantages of LED’s compared with the conventional incandescent lights?
There are several obvious advantages LED’s have over traditional incandescent light bulbs, they are as follows:

  • Low power consumption – energy saving
  • Long lasting
  • Cold lighting
  • Ruggedness
  • Small size and weight
  • Fast switch times
  • Simple to use
Is lifespan reduced if the LED’s are frequently turned on and off?
Unlike discharge lamps, LED’s are semiconductors and their life span is not affected by the number of times they are turned on and off.
What are the factors that affect the lifespan of LED’s?
LED light bulbs behave differently from traditional lights. Factors that will affect the life span of LED’s include power supply, ambient temperature and components. High quality heat sinks have to be designed to prevent premature failure of LED’s.Higher ambient temperatures than that for which the product is rated also reduces the life of the LED’s.

Could you give a more detailed explanation about these LED advantages?
Yes. Currently available LED’s are more energy efficient than incandescent bulbs, but less than florescent bulbs with the same light output.The power consumption of popular LED’s ranges from 30mW to 200mW. People can save money & energy by using LED’s instead of equivalent incandescent decorative bulbs. The rated average working life of LED is around 50,000 hours compared with 1,000 hours of incandescent bulbs. LED’s emit cold lights as working LED’s generate very small amount of heat, so LED’s are much safer than equivalent incandescent light bulbs in terms of danger of fire. LED’s don’t have filaments to heat up in order to emit lights just like the case of incandescent bulbs. Lights are emitted from LED’s as a result of energy exchange occurring in the different semiconductor materials an LED is made of. LED’s are usually shielded with solid transparent plastic materials so they are more rugged than incandescent and florescent bulbs that are usually sealed with glass. LED’s can be powered by either AC voltage or DC voltage. The circuit that is required to appropriately drive LED’s is much simpler than that for florescent bulbs.

Are they more efficient than traditional lighting?
LED’s work in a completely different way to traditional lighting as they typically use 75% less energy whilst producing the same amount of light.
What are the advantage/disadvantage of Incandescent light bulbs?
The most significant disadvantage is the light output limitation of LED. Currently available LED’s emit limited amount of lights at a relatively small angle range, while incandescent and florescent light bulbs illuminate in all directions and give out much more brightness.The second significant disadvantage is the high prices of LED’s. Currently available LED’s in the market are 3 ~ 10 times more expensive than equivalent incandescent light bulbs. This is why some customers still hesitate to buy LED products even though LED’s have so many obvious advantages over incandescent bulbs and people actually can save money by using LED products in the long run.

Is there an equation to compare LED’s to incandescent watts?
Unfortunately, there is not a simple formula to convert an LED light output into an incandescent equivalent. It depends on the LED manufacturer and colour temperature of the lamp. Here is a general rule-of-thumb:

  • Incandescent emits 8-30 lumens per watt, compact fluorescent emits 30-60 lumens per watt, and linear fluorescent emits 40-90 lumens per watt. Depending on the quality of LED, they currently fall in the 40-130.
  • Lumens per watt category; this of course is suggestive and is ever changing, as is LED technology.
Why should I buy LED bulbs?
With rising energy costs, it is critical to improve your household’s energy efficiency. Around 11% of an average British household’s electrical usage is attributed to lighting. One of the easiest steps you can take towards greater energy efficiency can be done in a matter of seconds – change your old light bulbs to LED bulbs.LED’s consume far less energy than incandescent, halogen, or compact fluorescent bulbs. You will save money and reduce carbon emissions – all from replacing a tiny light bulb!

What are the economic advantages of using LED’s over conventional light sources?
Although the cost of conventional light bulbs is less than LED versions, they do not take into account the operational and maintenance cost of the lighting system. LED’s, on average last significantly longer, reduce maintenance and lamp replacement cost. This reduces cost of labour to replace lamps and the cost of new lamps at the end of lamp life cycle. LED’s, also consume less energy. Overall the cost of a LED lamp can thus be significantly lower than conventional lighting systems when they are compared side by side over time.
Installing new fittings is going to be expensive. Is it easier/cheaper to leave existing fittings as they are?
We offer retro fit lamps which looks like the traditional lamps and is installed into the existing fitting in the same way with little to no modifications required. Retrofit lamps is generally the most cost effective and easiest way to upgrade to energy efficient LED lighting.Installing new luminaires/fittings should be considered the best option where your current fittings are old and rewiring is required. This will generally be more expensive as more work is involved. New fittings/luminaires will also benefit from being designed to incorporate features such as better thermal management, driver, IP rating and dimming, offering a more rounded all in one solution.

Where is it appropriate to install LED bulbs?
LED light bulbs are appropriate when you need powerful directional lighting. Presently, LED’s excel over other bulbs in spot and flood lighting applications. Track lighting, spot lighting, canister lights, and outdoor flood lights are currently the most common places to use and replace incandescent bulbs to LED versions.
Do your LED bulbs contain mercury?
Our LED bulbs are mercury-free and meet the strict requirements of the Restriction of Hazardous Substances Directive (RoHS).
Do LED bulbs work in regular light sockets and fixtures?
Yes. LED light bulbs will work in most standard light sockets and fixtures, such as Edison screw-in base and MR16 track lighting.
Are LED’s easy to install?
Yes. Installing or changing an LED light bulb is like changing any other bulb, with the advantage that you’ll need to change it far less often!
What precautions are/can be taken when mounting LED drivers?
LED drivers need to be mounted in a ventilated space. Access to the driver needs to be provided for general maintenance purposes. The IP (ingress protection) rating of the driver needs to be considered before finalising the mounting location of the driver (only those drivers designed for outdoor environments can be installed outdoors). The distance between the driver and the light source needs to be taken into consideration to prevent voltage drop that results in reduced output of the LED’s.
How bright are LED bulbs? What is the light quality of an LED bulb?
The light quality of LED is terrific – equal to or better than conventional bulbs. Because there is no radiant glare, LED’s produce a cleaner light quality. Most people discuss light brightness in terms of lumens. One important thing to understand is that colour temperature is an important consideration alongside lumens.For example, a light bulb may have high lumens, but a low colour temperature, resulting in poor colour rendition. So, although a light is supposed to have a high light output, it’s low colour temperature renders visible objects very poorly. A good experiment you can do is to observe a yellow-coloured street light at night – the light gives off a lot of light (high lumen output), but it is still very difficult for your eyes to perceive objects. Now, contrast this with a light bulb that may or may not have high lumen output, but has a higher (whiter) colour temperature. In every case, even at a lower lumen output, a higher colour temperature means that your eyes will better perceive objects and colour. So, although LED light bulbs may have lower lumens than conventional bulbs, they compensate with their excellent colour temperature. Especially true with outdoor lighting, a higher colour temperature (whiter bulb) translates into better lighting.

Do LED bulbs give of heat?
LED light bulbs only give off ambient, room temperature heat around the LED itself. One reason LED’s are efficient is due to the low amount of heat around the LED diode junction. To accomplish this efficiency, heatsinks are required to draw heat away from the LED junction. The heatsink may get hot, so be careful not to touch it.
What transformer can I use with MR16 LED bulbs?
You should use a transformer rated at 12V only. As good general practice, please test your transformer’s voltage before using LED or any other light bulb. A transformer not operating at 12V will create bulb flicker and potentially ruin the bulb.
How do I know what type of driver is required by an LED product?
The LED rating of a product is usually noted in milliamps, mA or volts, V. Products rated in mA can be used with a constant current driver; while those rated in volts can be run on a constant voltage driver. LED’s designed for constant current drivers cannot run with constant voltage drivers without damaging it.
Is low voltage or a mains circuit better for an LED?
We generally recommend that you use mains voltage unless you are using an LED driver to run 12V lamps. Drivers and transformers not designed to run LED bulbs will cause premature failure and are not covered under our warranty. This issue relates to all LED lamps and bulbs irrespective of manufacturer.We always recommend that you consult an electrician who is familiar with LED lighting products if you are unsure.

Do your LED’s work with dimmers?
We do not recommend using our LED bulbs with traditional dimmer switches, as it may diminish the lifetime of the bulb.

However dimming can be achieved by varying the input voltage to the LED (Only for low voltage MR16 and MR11 Models).

What is the minimum and maximum working voltage for MR16 and MR11′s?
The minimum and maximum working voltage for MR16 and MR11′s is 7 to 15 Volts although we recommend a constant 12V input. Any voltage below 12V will decrease the light intensity.
Why is the colour of LED important?
Most LED’s are monochromatic. Light colour is associated with the light wavelength. LED’s are made with different semiconductor materials emit lights in different wavelengths. LED light wavelengths range from 400 nanometers (blue) to 800 nanometers (red) and 2700 Kelvin to 7000 Kelvin for white. The colours of popularly available LED’s in the market are red, orange, amber, yellow, green, blue and white.
You make all these amazing claims about your products but, how can I be assured they will actually deliver these promises of efficiency and light output?
We appreciate that, as LED’s are a new technology there is a lot of inconsistency out there in performance and claims made. We thoroughly test all our fittings on site and all our designs are independently tested for performance.
How do we know that your LED lamps are better than your competitors?
We are not tied to any one manufacturer of LED’s so we can afford to test various products from different manufacturers to ensure we are getting the best components and designs for our products.We specify technology that protects the LED’s ensuring no matter what the indoor or outdoor conditions are, we are confident that the LED life always remains within its optimum operating parameters.

We ensure all of our components are of the highest quality and are tested by 3rd party test houses. We are also aware of other potential issues with changing from the traditional lighting to LED. We have components within the system we provide to alleviate these problems, otherwise within a couple of years the clients will see many failed power supplies on the lights.

Can I get financing to help fund my lighting upgrade?
Kyman Ledtex works with a number of finance companies that specialise in providing finance for energy saving projects. The repayment terms can often be arranged so that the monthly energy cost savings contributes significantly towards meeting the monthly finance costs. If this might be of interest, contact us for further information.Want to find out more?

Visit some useful sites below on the future of LED Lighting.