- What are LEDs?
LED is actually an abbreviation for light emitting diode, essentially it is a semi-conductor type of electronic component that produces light. A LED is NOT anything like a traditional light bulb where electricity is used to heat a tungsten filament until it glows (similar to a toaster), these are inefficient and gradually evaporate until the burn out.
LEDs are very similar to a solar panel in reverse. Instead of receiving light and producing electricity the silicon excites when electricity hits the diode and produces light. LED is by far one of the most commercially viable energy efficient light sources that produce significantly more light per watt than most other forms of traditional lighting. The physical size of a LED is very small (approx. 3-10mm diameter for DIP and 3-10mm square for SMD) and due to this they are VERY versatile.
Typical lamps require a 240 volts to operate but LED can use as little as 2 or 3 volts, although there is 12V halogen lighting the amount of extra power required to convert the voltage down is significantly reduced as LED power consumption is quite low in comparison.
For more information visit the Wikipedia page on LEDs.
- Can LED lights be dimmed?
Yes!Some LED Lighting can be dimmed depending on the electronics and power supply used.LEDs which work on 12V can usually be dimmed on either the 12V or 240V side. It can be tricky to determine sometimes, so we have created a section for DIMMABLE LEDS.
- What is LED Lighting?
LED lighting has been around for a long time, however only recently has new technology and improvements been made to use the light produced as a domestic source. Most commonly used for VCR indicators, the famous blue ON light on the Sony Playstation 2 and similar small scale applications.
LEDs are a solid state electronic device which means there are huge reductions in breakages in shipping and reduction in hazardous materials required for the light to operate. No glass, no infra red, no ultra violet damage, no mercury, no pressurised gases, no explosions, and almost no fire risk due to significant heat production. LED is the safer way of lighting. Heat is a direct by-product of traditional bulbs, whilst similar to solar panels, a reduction in heat improves efficiency with LED technology.
Different properties of LED chips on circuit boards can create most colours of light in the colour spectrum. For many years changes in lighting from incandescent to halogen to fluorescent to metal halide were all just different ways of doing the same thing with different effects.
LED technology has changed the way we think about lighting and reinvented the light globe. The same advancements that allowed faster computer chips and similar technology efficiencies has grown to the LED, allowing brighter, smaller, less expensive and more advanced lighting.
For more information visit the Wikipedia page on LED Lighting
- What are the advantages of LED?
Just to name a few...
Shock resistant: LED lights are a solid state designed component due to this they are reasonably resistant to breakages caused by transit, being dropped or similar events.
Explosion resistant: Unlike conventional lighting LED lights do not operate at extremely high temperatures in a vacuum which can cause explosions when failing.
Multi-dimensional Controllability: A nice big word to remember, MDC is a term to describe the possibilities with LED lighting. Because LED lights come in a vast range of colours, sizes, shapes, bases, designs, efficiencies, fixings etc. the possibilities of easily developing a custom size fitting are almost limitless.
Savings: LED lights run with up to 95% less energy consumption compared to most Halogen and incandescent globes and up to staggering 60%+ less energy consumption compared to fluorescent globes and tubes which means you not only save money but you're helping save our environment.
Safety: LED lights are safer to use in the home, pose a lower threat to house fires due to heat, provide protection against rising energy costs and are electrically safe and are cool to touch for childrens lamps.
Light Quality: LED lights more focused lighting provides ample light for all conditions, whether you are replacing tubes, halogens, incandescents or CFLs you will instantly find the light a more stable, crisp, clear light with distinctive colouring to suit.
Instant ON: LED lights have the ability to be turned on and off and to full capacity quicker than any other form of lighting. There is no flickering like CFLs and no lengthy warm up times.
Dimming: LED lights can be dimmed provided that the electronic components allow this. Generally you will need to use a LED driver and suitable dimmer pot to allow this.
Life: LED lights in general have a life expectancy of 25,000 - 100,000 hours. This means that even operating for 8 hours a day you should see your lights exceed 15 years with our high quality LED lights.
Temperature: LED lighting produces far less heat than conventional lighting, in some cases where an array of lights are used you can even save on your cooling bills!
- How long do LEDs last?
Typically the industry standard for LED is around 50,000 hours to 70% lumen maintenance. As most things do they will degrade initially up to 10% over the first 5,000 hours of operation followed by a slower rate of decline up to 30% loss after 50,000 hours. One thing to understand when quoting how long a LED lasts for is that most chips have a 50,000 hour rating. Whether it will reach 50,000 hours in the real world where the temperature changes and voltage/current fluctuation occurs can affect poor quality LED luminaries.Commercially available LEDs are generally blue LEDs with a fluorescence applied to them and its the fluorescence that degrades not the chip/diode itself. It also depends if the LEDs are being "driven" hard or voltage is variable. The types of commercial dome-type LEDs available these days are called "static sensitive" and can be badly affected by variations in voltage and current - that's why they're OK on batteries (if not run too low) but sensitive to other forms of power like 240VAC/12VAC transformers.
Although, the life span of a LED is vastly longer than that of incandescent, fluorescent or HID lamp sources and generally the light emitting diode never really burns out, thus the product life span is measured by lumen depreciation.
The Illuminating Engineering Society's (IES) current standard for calculating the life of an LED as the point at which the LED reaches 30 percent lumen depreciation.
Remember, a 100,000-hour rating is not equivalent to lamp life rating. LED life is rated where it has reached 30 percent lumen depreciation. At 100,000 hours an LED would still be operating, but at a decreased lumen output.
This can mean over 15 Years of light from one light used for 5 hours a day. Compared to an incandescent bulb, which lasts 1,000 hours, a halogen bulb lasts 2,000 hours, and a compact fluorescent bulb which are lucky to last up to 10,000 hours.
The extremely long life of an LED bulb will virtually eliminate your maintenance costs. There will be no need to change light bulbs throughout the year.
LED convert almost all the energy used into the light output, making them a highly efficient light source. With minimal heat generated, LED are safe to the touch and do not produce any harmful UV rays.
- Do I need a LED Driver?
Traditionally LED bulbs have been driven using series resistance, this usually works okay if there are no external loads applied to the circuit which may affect it. If an external heavy load is applied when an LED bulb is running for example as the compressor or pump switch is turned on the current and the voltage immediately decrease. These dips in voltage and current seriously affect the lifetime of the LED bulb.
Examples of heavy inductive loads include swimming pool pumps and large refrigerators, these can cause traditional incandescent and halogen bulbs to fail at times.
However, Constant current LED drivers have a small integrated circuit incorporated which sense any voltage variations within the lighting circuit and will automatically compensate for any losses.
LED bulbs are infinitely more susceptible to current and voltage spikes due to their low start-up demand.
Some globes now even have the technology built in to withstand a wider range of input power where typically halogens and incandescents would have failed.
Low battery voltages can cause heat buildup due to increased resistance and high voltages can cause the LED to overdrive risking premature failure or dimming. Also in the manufacturing process, there are sometimes minute variations in the chemical substrate, this can cause fluctuations in current demand. Temperature is also a serious consideration in that it is hard to control without proper current regulation. Once again, there are some LED lamps which have integrated thermal management and as time goes on this will become more popular.As current increases the temperature correspondingly rises. This can cause the voltage to rise across the junction leading once again to early failure if not properly regulated.We always suggest if you are looking to change over your 12V halogen lamps, either swap to a GU10 fitting that's 240V or get a suitable LED driver.
- Are LEDs too directional?
Not all of them..While all diodes release light, most don't do it very effectively. In an ordinary diode, the semiconductor material itself ends up absorbing a lot of the light energy and push the rest through the plastic housing.Surface mounted LEDs (SMD chips) are specially constructed to release a large number of photons outward. Additionally, they are housed in a small bulb or lens that concentrates the light in a particular direction, where most of the light from the diode bounces off the sides of the bulb, traveling on through the rounded end.<insert LED_CREE_IMAGE>
- Can temperature affect LEDs?
Yes!LED fixtures must be designed with junction temperature thermal management as a key component and use the correct LED chips. These products will then be robust enough to operate in most ambient temperature applications. Unlike fluorescent sources, cold temperatures do not impact the performance of LEDs.We have seen some real shockers in the past few years in which manufacturers and resellers boast high light output and lifespan but when put into a ceiling degrade quicker than you can imagine.
- Can I replace my lights with LEDs?
YES! LED lamps come in a variety of bases and fittings such as the standard Bayonet (B22) and Edison (E27) screw in globes and downlight lamps with GU10 and MR16 bases.As time progresses rather than having replacement lamps most manufacturers will start to produce complete fittings that incorporate thermal management, CBUS compatibility, heat sink and connection points. This is mainly due to the long life span of LED technology where you may never have to change a light globe again!
- What is a lumen?
A lumen is a standard reference for an amount of light.
According to Wikipedia, "If a light source emits one candela of luminous intensity into a solid angle of one steradian, the total luminous flux emitted into that solid angle is one lumen. Alternatively, an isotropic one-candela light source emits a total luminous flux of exactly 4π lumens. The lumen can be thought of casually as a measure of the total amount of visible light emitted." For example, a standard 100 Watt incandescent bulb emits about 1300 lumens.
- What is junction temperature?
Junction temperature is the temperature at the point where an individual diode connects to its base. Maintaining a low junction temperature increases output and slows LED lumen depreciation. Junction temperature is a key metric for evaluating an LED product's quality and ability to deliver a long life expectancy.
The three things affecting junction temperature are: drive current, thermal path, and ambient temperature. In general, the higher the drive current, the greater the heat generated at the die. Heat must be moved away from the die in order to maintain expected light output, life, and color. The amount of heat that can be removed depends upon the ambient temperature and the design of the thermal path from the die to the surroundings. [Source: DOE]The Department of Energy advises: "Heat management and an awareness of the operating environment are critical considerations to the design and application of LED luminaires for general illumination. Successful products will use superior heat sink designs to dissipate heat, and minimize junction temperature. Keeping the junction temperature as low as possible and within manufacturer specifications is necessary in order to maximize the performance potential of LEDs."
- What is lux?
Lux is a measure of lumens per square meter.
According to Wikipedia, "The difference between the lux and the lumen is that the lux takes into account the area over which the luminous flux is spread. 1000 lumens, concentrated into an area of one square meter, lights up that square meter with an illuminance of 1000 lux. The same 1000 lumens, spread out over ten square meters, produces a dimmer illuminance of only 100 lux."For more information on LUX click here to visit the Wikipedia page.
- What is SMD or High Power LEDs?
High power LEDs utilize the latest LED technology. These are the surface mount type or SMD LEDs. Small as they are, they generate high heat which must be dissipated or moved away from the LED in order for the LED to live the expected life time of 50,000 hours. To do that, most manufacturers have incorporated an aluminum body with fins to increase the total area that the heat can escape to and be dissipated. The higher the operating current, the higher the heat load to be dissipated. That means more fins, or more thin and longer fins are required. In the case of one newly developed design, the LED bulb incorporates water to assist with the dissipation of heat and some have even gone to the extent of having small fans inside the lamp.
- What do the base types mean?
MR16 and MR11 are typically types of multifaceted reflector lamps (MR), in which the number (16/11) relates to diameter of the facia in eights of an inch. For example 16 eights of an inch equals 51mm. These lamps are typically 12 volt halogens and powered by a 240V transformer - which realistically is plain stupid because more power is consumed by the transformer.
GU10 is a derivative of the MR16 in which typically has a similar facia but uses a bayonet type base.
E27 and E14 generally found in Australia are types of Edison screw bases. There are other sizes ranging from E5 to E40 and are common across the world. The number allocated relates to diameter of the base.
B22 and B15 are very similar to the Edison screw bases, but are instead of a bayonet nature. These bayonet cap bases usually have 2 prongs on either side of the base and are fixed by a push and twist action.
PAR is also a unit of bulb measurement. In this system of lamp identification the first number listed denotes the maximum diameter of the lamp expressed as a number of 1/8's of an inch.
For example, some common sizes are:PAR-64's (8"), PAR-56 (7"), PAR-46 (5.75"), PAR-38 (4.75"), PAR-36 (4.5").
- Where can LEDs be used?
Lighting Matters can supply LED lighting for the following applications:
- decorative lights
- pendant lights
- under or inside cabinets
- kitchen splash back lighting
- recessed lighting
- feature wall lighting
- home theatre / media room
- entertainment area
- patio / garden
- interior and exterior special effect lighting (eg. Hotel, restaurant, casino, water feature, landmark)
- landscape lighting for gardens, parks, pools and spas
- wall washers
- strip lighting
- accent lighting
- cove lighting
- small spot lighting
- path lights
- in-ground and underwater lights
- flood Lighting
- high or low bay replacement
- task lighting
- street lighting
- refrigerated display case lighting
- general merchandise lighting, eg. creating effects and moods based on warm/cold colours
- display case lighting
- concerts feature effect lighting
- concert hall and theatre lighting
- tv studios, stage lighting
- bars, clubs and restaurant
Safety and security:
- exit / entry signs
- emergency lighting
- outdoor areas
- parking lots
- street and highway lights and signs
- What LED lamp do I need to replace my...?
It is sometimes hard to determine exactly what wattage LED light you need to replace existing lamps.Typically halogen and incandescent lamps have a very low luminous efficacy or lumens per watt. Such as 15lm/w for halogens.Compact fluorescents are a bit more efficient at producing light and sit around the 50-60lm/w.When comparing these lamps to LED equivalents there are a number of things that need to be considered before making your purchase.1. Beam angle - if your existing lamp has a 60 degree beam then you should choose an LED with a similar beam angle, if you go for a narrower beam angle, chances are the output will look brighter but you may not spread the light properly, but if the beam is wider then the output will more than likely be softer and of course what you are actually illuminating can be compromised.2. Colour - the colour of a LED lamp can affect the lumen output of a LED, where typically the cooler white you choose the brighter it will be for the equivalent wattage.3. Lumen output - in the real world there is a lot of over-stating of lumen output. For example, most halogens are rated at 850-900lm, but in practice they may only output 650-750lm. The same thing applies to LED lamps, where lamps may be stated at 600lm but only output 400lm. Due to this we always recommend using well known branded products such as CREE, Philips and Brightgreen.4. Wattage - most of the time, the higher the wattage the brighter the lamp will be. Generally, to replace a 50W halogen or 60W incandescent you would use a 10W LED. A 35W halogen or 40W incandescent could be replaced by a 5W LED.For more information on purchasing LED lighting, visit our LED Buying Guide